Phase 2: End of phase 1, evaluate, learn from experience and switch to applying risk-based supervision method, aiming at 3 main pillars: financial safety index, corporate governance, information transparency.
3.2.1.4. Perfecting business evaluation criteria
Based on the monitoring results, the monitoring agency needs to take timely measures for each insurance company depending on the monitoring results. Therefore, it is necessary to have a set of criteria for evaluating insurance companies based on the assessment of risk categories, assessment of risk prevention measures of the company as well as additional criteria such as capital, solvency, and revenue to give a rating level for each insurance company.
Maybe you are interested!
-
Pre-tax Profit of Bidv Tien Giang in the Period 2011-2015
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zt2a3gsnon-credit services, joint stock commercial bank
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At that time, the Branch had to set aside a provision for credit risks, which reduced the Branch's income.
Chart 2.2. Pre-tax profit of BIDV Tien Giang in the period 2011-2015
Unit: Billion VND
140
120
100
80
60
40
20
0
63.3
80.34
89.29
110.08
131.99
2011 2012 2013 2014 2015
Profit before tax
(Source: Report on the implementation of the annual business plan of the General Planning Department of BIDV Tien Giang [24])
However, through chart 2.2, it can be seen that BIDV Tien Giang's profit is still increasing continuously, and its operating efficiency is currently leaking. This is a contribution of non-credit services, and this service segment will be increasingly focused on growth by BIDV Tien Giang to ensure the highest profit safety because credit activities have many potential risks. At the same time, focusing on developing non-credit services is consistent with one of the contents of restructuring the financial activities of credit institutions in the project "Restructuring the system of credit institutions in the period 2011-2015" approved by the Prime Minister in Decision No. 254/QD-TTg dated March 1, 2012 [14]: "Gradually shifting the business model of commercial banks towards reducing dependence on credit activities and increasing income from non-credit services".
2.2. Current status of non-credit service development at BIDV Tien Giang.
2.2.1. BIDV Tien Giang has deployed the development of non-credit services in recent times.
Along with the development of the Head Office, BIDV Tien Giang's products and services are constantly improved and deployed in a diverse manner to ensure provision for many different customer groups in the area: individual customers, corporate customers, and financial institutions. Typical services are as follows: Payment services, treasury services, guarantee services, card services, trade finance, other services: Western Union, insurance commissions, consulting services, foreign exchange derivatives trading, e-banking services,...
2.2.1.1. Payment services:
In accordance with the Prime Minister's Project to promote non-cash payments in Vietnam [15], banks in Tien Giang province have continuously developed payment services to reduce customers' cash usage habits through card services and electronic banking services such as: salary payment through accounts, focusing on developing card acceptance points, developing multi-purpose cards, paying social insurance by transfer, paying bills through banks, etc.
Chart 2.3. Net income from payment services in the period 2011-2015
Unit: Million VND
6000
5000
4000
3000
2000
1000
0
3922 4065
4720 5084 5324
2011 2012 2013 2014 2015
Net income from payment services
(Source: Report on the implementation of the annual business plan of the General Planning Department of BIDV Tien Giang [24])
Along with the technological development of the entire system, BIDV Tien Giang has a payment system with a fairly stable transaction processing speed, bringing many conveniences to customers. The results of observing chart 2.3 show that the income from payment services that the Branch has achieved has grown over the years but the speed is not high and the products are not outstanding compared to other banks. Domestic payment products such as: Online bill payment, electricity bills, water bills, insurance premiums, cable TV bills, telecommunications fees, airline tickets, etc. bring many conveniences to customers. Regarding international payment, this is an indispensable activity for foreign economic activities, BIDV Tien Giang is providing international payment methods for small enterprises producing agriculture, aquatic food and seafood that have credit relationships with banks in industrial parks in Tien Giang province such as: money transfer, collection, L/C payment.
2.2.1.2. Treasury services:
BIDV Tien Giang always focuses on ensuring treasury safety and currency security, always complies with legal regulations, and minimizes risks in operations such as: counting and collecting money from customers, receiving and delivering internal transactions, collecting from the State Bank (SBV) or other credit institutions, receiving ATM funds, bundling money, etc. BIDV Tien Giang's treasury service management department is always fully equipped with modern machinery and equipment such as: money transport vehicles, fire prevention tools, money counters, money detectors, magnifying glasses, etc. to ensure absolute safety in treasury operations, immediately identifying real and fake money and other risks that may affect people and assets of the bank and customers. In addition, implementing regulation 2480/QC dated October 28, 2008 between the State Bank of Tien Giang province and the Provincial Police on coordination in the fight against counterfeit money, in the 3-year review of implementation, BIDV Tien Giang discovered, seized and submitted to the State Bank of Tien Giang province 475 banknotes of various denominations and was commended by the Provincial Police and the State Bank of Tien Giang province [17].
Chart 2.4. Net income from treasury services in the period 2011-2015
Unit: Million VND
350
300
250
200
150
100
50
0
105 122
309 289 279
2011 2012 2013 2014 2015
Net income from treasury services
(Source: Report on the implementation of the annual business plan of the General Planning Department of BIDV Tien Giang [24])
However, as shown in Figure 2.4, income from treasury operations is not high and fluctuates. Specifically, in the period 2011-2013, net income increased and increased most sharply in 2013, then in the period 2013-2015, there was a downward trend. This fluctuation is due to the fact that fees collected from treasury services are often very low and can even be waived to attract customers to use other services.
2.2.1.3. Guarantee and trade finance services:
BIDV Tien Giang, thanks to the advantages of the province and the favorable location of the Branch, has continuously focused on developing income from guarantee services and trade finance.
Chart 2.5. Net income from guarantee and trade finance services in the period 2011-2015
Unit: Million VND
14000
12000
10000
8000
6000
4000
2000
0
5193 5695
2742 3420
8889
3992
11604 12206
5143 5312
2011 2012 2013 2014 2015
Net income from guarantee services Net income from Trade Finance
(Source: Report on the implementation of the annual business plan of the General Planning Department of BIDV Tien Giang [24])
Through chart 2.5, we can see that BIDV Tien Giang's income from guarantee services and trade finance has grown over the years. The reason is: Among BIDV Tien Giang's corporate customers, the construction industry is the industry with the highest proportion of customers after the trading industry, this is a group of customers with potential to develop guarantee services. The second group of customers is corporate customers in the fields of agricultural production, livestock and seafood processing with high import and export turnover in the area.
are the target of trade finance development. In addition, BIDV Tien Giang also focuses on continuously developing these customer groups to increase revenue for many other products and services in the future.
2.2.1.4. Card and POS services:
As a service that BIDV Tien Giang has recently developed strongly, it can be said that this is a very potential market and has the ability to develop even more strongly in the future. Card services with outstanding advantages such as fast payment time, wide payment range, quite safe, effective and suitable for the integration trend and the Project to promote non-cash payments in Vietnam. Cards have become a modern and popular payment tool. BIDV Tien Giang early identified that developing card services is to expand the market to people in society, create capital mobilized from card-opened accounts, contribute to diversifying banking activities, enhance the image of the bank, bring the BIDV Tien Giang brand to people as quickly and easily as possible. BIDV Tien Giang is currently providing card types such as: credit cards (BIDV MasterCard Platinum, BIDV Visa Gold Precious, BIDV Visa Manchester United, BIDV Visa Classic), international debit cards (BIDV Ready Card, BIDV Manu Debit Card), domestic debit cards (BIDV Harmony Card, BIDV eTrans Card, BIDV Moving Card, BIDV-Lingo Co-branded Card, BIDV-Co.opmart Co-branded Card). These cards can be paid via POS/EDC or on the ATM system. In addition, with debit cards, customers can not only withdraw money via ATMs but also perform utilities such as mobile top-up, online payment, money transfer,... through electronic banking services.
In order to attract customers with card services, BIDV Tien Giang has continuously increased the installation of ATMs. As of December 31, 2015, BIDV Tien Giang has 23 ATMs combined with 7 ATMs in the same system of BIDV My Tho, so the number of ATMs is quite large, especially in the center of My Tho City, but is not yet fully present in the districts. Basic services on ATMs such as withdrawing money, checking balances, printing short statements,... BIDV ATMs accept cards from banks in the system.
Banknetvn and Smartlink, cards branded by international card organizations Union Pay (CUP), VISA, MasterCard and cards of banks in the Asian Payment Network. From here, cardholders can make bill payments for themselves or others at ATMs, by simply entering the subscriber number or customer code, booking code that service providers notify and make bill payments.
Chart 2.6. Net income from card services in the period 2011-2015
Unit: Million VND
3500
3000
2500
2000
1500
1000
500
0
687
1023
1547
2267
3104
2011 2012 2013 2014 2015
Net income from card services
(Source: Report on the implementation of the annual business plan of the General Planning Department of BIDV Tien Giang [24])
Through chart 2.6, it can be seen that BIDV Tien Giang's card service income is constantly growing because the Branch focuses on developing businesses operating in industrial parks, which are the source of customers for salary payment products, ATMs, BSMS. Specifically, there are companies such as Freeview, Quang Viet, Dai Thanh, which are businesses with a large number of card openings at the Branch, contributing to the increase in card service fees [25].
Table 2.6. Number of ATMs and POS machines in 2015 of some banks in Tien Giang area.
Unit: Machine
STT
Bank name
Number of ATMs
Cumulative number of ATM cards
POS machine
1
BIDV Tien Giang
23
97,095
22
2
BIDV My Tho
7
21,325
0
3
Agribank Tien Giang
29
115,743
77
4
Vietinbank Tien Giang
16
100,052
54
5
Dong A Tien Giang
26
97,536
11
6
Sacombank Tien Giang
24
88,513
27
7
Vietcombank Tien Giang
15
61,607
96
8
Vietinbank - Tay Tien Giang Branch
6
46,042
38
(Source: 2015 Banking Activity Data Report of the General and Internal Control Department of the Provincial State Bank [21])
Through table 2.6, the author finds that the number of ATMs of BIDV Tien Giang is not much, ranking fourth after Agribank Tien Giang, Dong A Tien Giang, Sacombank Tien Giang. The number of POS machines of BIDV Tien Giang is very small, only higher than Dong A Tien Giang and BIDV My Tho in the initial stages of merging the BIDV system. Besides, BIDV Tien Giang has a high number of cards increasing over the years (table 2.7) but the cumulative number of cards issued up to December 31, 2015 is still relatively low compared to Agribank, Vietcombank, Dong A (table 2.6).
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Solutions for tourism development in Tien Lang - 10
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- District People's Committees and authorities of communes with tourist attractions should support, promote, and provide necessary information to people, helping them improve their knowledge about tourism. Raise tourism awareness for local people.
*
* *
Due to limited knowledge and research time, the thesis inevitably has shortcomings. Therefore, I look forward to receiving guidance from teachers, experts as well as your comments to make the thesis more complete.
Chapter III Conclusion
Through the issues presented in Chapter II, we can come to some conclusions:
Based on the strengths of available tourism resources, the types of tourism in Tien Lang that need to be promoted in the coming time are sightseeing and resort tourism, discovery tourism, weekend tourism. To improve the quality and diversify tourism products, Tien Lang district needs to combine with local cultural tourism resources, at the same time combine with surrounding areas, build rich tourism products. The strengths of Tien Lang tourism are eco-tourism and cultural tourism, so developing Tien Lang tourism must always go hand in hand with restoring and preserving types of cultural tourism resources. Some necessary measures to support and improve the efficiency of exploiting tourism resources in Tien Lang are: strengthening the construction of technical facilities and labor force serving tourism, actively promoting and advertising tourism, and expanding forms of capital mobilization for tourism development.
CONCLUDE
I Conclusion
1. Based on the results achieved within the framework of the thesis's needs, some basic conclusions can be drawn as follows:
Tien Lang is a locality with great potential for tourism development. The relatively abundant cultural tourism resources and ecological tourism resources have great appeal to tourists. Based on this potential, Tien Lang can build a unique tourism industry that is competitive enough with other localities within Hai Phong city and neighboring areas.
In recent years, the exploitation of the advantages of resources to develop tourism and build tourist routes in Tien Lang has not been commensurate with the available potential. In terms of quantity, many resource objects have not been brought into the purpose of tourism development. In terms of time, the regular service time has not been extended to attract more visitors. Infrastructure and technical facilities are still weak. The labor force is still thin and weak in terms of expertise. Tourism programs and routes have not been organized properly, the exploitation content is still monotonous, so it has not attracted many visitors. Although resources have not been mobilized much for tourism development, they are facing the risk of destruction and degradation.
2. Based on the results of investigation, analysis, synthesis, evaluation and selective absorption of research results of related topics, the thesis has proposed a number of necessary solutions to improve the efficiency of exploiting tourism resources in Tien Lang such as: promoting the restoration and conservation of tourism resources, focusing on investment and key exploitation of ecotourism resources, strengthening the construction of infrastructure and tourism workforce. Expanding forms of capital mobilization. In addition, the thesis has built a number of tourist routes of Hai Phong in which Tien Lang tourism resources play an important role.
Exploiting Tien Lang tourism resources for tourism development is currently facing many difficulties. The above measures, if applied synchronously, will likely bring new prospects for the local tourism industry, contributing to making Tien Lang tourism an important economic sector in the district's economic structure.
REFERENCES
1. Nhuan Ha, Trinh Minh Hien, Tran Phuong, Hai Phong - Historical and cultural relics, Hai Phong Publishing House, 1993
2. Hai Phong City History Council, Hai Phong Gazetteer, Hai Phong Publishing House, 1990.
3. Hai Phong City History Council, History of Tien Lang District Party Committee, Hai Phong Publishing House, 1990.
4. Hai Phong City History Council, University of Social Sciences and Humanities, VNU, Hai Phong Place Names Encyclopedia, Hai Phong Publishing House. 2001.
5. Law on Cultural Heritage and documents guiding its implementation, National Political Publishing House, Hanoi, 2003.
6. Tran Duc Thanh, Lecture on Tourism Geography, Faculty of Tourism, University of Social Sciences and Humanities, VNU, 2006
7. Hai Phong Center for Social Sciences and Humanities, Some typical cultural heritages of Hai Phong, Hai Phong Publishing House, 2001
8. Nguyen Ngoc Thao (editor-in-chief, Tourism Geography, Hai Phong Publishing House, two volumes (2001-2002)
9. Nguyen Minh Tue and group of authors, Hai Phong Tourism Geography, Ho Chi Minh City Publishing House, 1997.
10. Nguyen Thanh Son, Hai Phong Tourism Territory Organization, Associate Doctoral Thesis in Geological Geography, Hanoi, 1996.
11. Decision No. 2033/QD – UB on detailed planning of Tien Lang town, Hai Phong city until 2020.
12. Department of Culture, Information, Hai Phong Museum, Hai Phong relics
- National ranked scenic spot, Hai Phong Publishing House, 2005. 13. Tien Lang District People's Committee, Economic Development Planning -
Culture - Society of Tien Lang district to 2010.
14.Website www.HaiPhong.gov.vn
APPENDIX 1
List of national ranked monuments
STT
Name of the monument
Number, year of decisiondetermine
Location
1
Gam Temple
938 VH/QĐ04/08/1992
Cam Khe Village- Toan Thang commune
2
Doc Hau Temple
9381 VH/QĐ04/08/1992
Doc Hau Village –Toan Thang commune
3
Cuu Doi Communal House
3207 VH/QĐDecember 30, 1991
Zone II of townTien Lang
4
Ha Dai Temple
938 VH/QĐ04/08/1992
Ha Dai Village –Tien Thanh commune
APPENDIX II
STT
Name of the monument
Number, year of decision
Location
1
Phu Ke Pagoda Temple
178/QD-UBJanuary 28, 2005
Zone 1 - townTien Lang
2
Trung Lang Temple
178/QD-UBJanuary 28, 2005
Zone 4 – townTien Lang
3
Bao Khanh Pagoda
1900/QD-UBAugust 24, 2006
Nam Tu Village -Kien Thiet commune
4
Bach Da Pagoda
1792/QD-UB11/11/2002
Hung Thang Commune
5
Ngoc Dong Temple
177/QD-UBNovember 27, 2005
Tien Thanh Commune
6
Tomb of Minister TSNhu Van Lan
2848/QD-UBSeptember 19, 2003
Nam Tu Village -Kien Thiet commune
7
Canh Son Stone Temple
2160/QD-UBSeptember 19, 2003
Van Doi Commune –Doan Lap
8
Meiji Temple
2259/QD-UBSeptember 19, 2002
Toan Thang Commune
9
Tien Doi Noi Temple
477/QD-UBSeptember 19, 2005
Doan Lap Commune
10
Tu Doi Temple
177/QD-UBJanuary 28, 2005
Doan Lap Commune
11
Duyen Lao Temple
177/QD-UBJanuary 28, 2005
Tien Minh Commune
12
Dinh Xuan Uc Pagoda
177/QD-UBJanuary 28, 2005
Bac Hung Commune
13
Chu Khe Pagoda
177/QD-UBJanuary 28, 2005
Hung Thang Commune
14
Dong Dinh
2848/QD-UBNovember 21, 2002
Vinh Quang Commune
15
President's Memorial HouseTon Duc Thang
177/QD-UBJanuary 28, 2005
NT Quy Cao
Ha Dai Temple
Ben Vua Temple
Tien Lang hot spring
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Qos Assurance Methods for Multimedia Communications
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low. The EF PHB requires a sufficiently large number of output ports to provide low delay, low loss, and low jitter.
EF PHBs can be implemented if the output port's bandwidth is sufficiently large, combined with small buffer sizes and other network resources dedicated to EF packets, to allow the router's service rate for EF packets on an output port to exceed the arrival rate λ of packets at that port.
This means that packets with PHB EF are considered with a pre-allocated amount of output bandwidth and a priority that ensures minimum loss, minimum delay and minimum jitter before being put into operation.
PHB EF is suitable for channel simulation, leased line simulation, and real-time services such as voice, video without compromising on high loss, delay and jitter values.
Figure 2.10 Example of EF installation
Figure 2.10 shows an example of an EF PHB implementation. This is a simple priority queue scheduling technique. At the edges of the DS domain, EF packet traffic is prioritized according to the values agreed upon by the SLA. The EF queue in the figure needs to output packets at a rate higher than the packet arrival rate λ. To provide an EF PHB over an end-to-end DS domain, bandwidth at the output ports of the core routers needs to be allocated in advance to ensure the requirement μ > λ. This can be done by a pre-configured provisioning process. In the figure, EF packets are placed in the priority queue (the upper queue). With such a length, the queue can operate with μ > λ.
Since EF was primarily used for real-time services such as voice and video, and since real-time services use UDP instead of TCP, RED is generally
not suitable for EF queues because applications using UDP will not respond to random packet drop and RED will strip unnecessary packets.
2.2.4.2 Assured Forwarding (AF) PHB
PHB AF is defined by RFC 2597. The purpose of PHB AF is to deliver packets reliably and therefore delay and jitter are considered less important than packet loss. PHB AF is suitable for non-real-time services such as applications using TCP. PHB AF first defines four classes: AF1, AF2, AF3, AF4. For each of these AF classes, packets are then classified into three subclasses with three distinct priority levels.
Table 2.8 shows the four AF classes and 12 AF subclasses and the DSCP values for the 12 AF subclasses defined by RFC 2597. RFC 2597 also allows for more than three separate priority levels to be added for internal use. However, these separate priority levels will only have internal significance.
PHB Class
PHB Subclass
Package type
DSCP
AF4
AF41
Short
100010
AF42
Medium
100100
AF43
High
100110
AF3
AF31
Short
011010
AF32
Medium
011100
AF33
High
011110
AF2
AF21
Short
010010
AF22
Medium
010100
AF23
High
010110
AF1
AF11
Short
001010
AF12
Medium
001100
AF13
High
001110
Table 2.8 AF DSCPs
The AF PHB ensures that packets are forwarded with a high probability of delivery to the destination within the bounds of the rate agreed upon in an SLA. If AF traffic at an ingress port exceeds the pre-priority rate, which is considered non-compliant or “out of profile”, the excess packets will not be delivered to the destination with the same probability as the packets belonging to the defined traffic or “in profile” packets. When there is network congestion, the out of profile packets are dropped before the in profile packets are dropped.
When service levels are defined using AF classes, different quantity and quality between AF classes can be realized by allocating different amounts of bandwidth and buffer space to the four AF classes. Unlike
EF, most AF traffic is non-real-time traffic using TCP, and the RED queue management strategy is an AQM (Adaptive Queue Management) strategy suitable for use in AF PHBs. The four AF PHB layers can be implemented as four separate queues. The output port bandwidth is divided into four AF queues. For each AF queue, packets are marked with three “colors” corresponding to three separate priority levels.
In addition to the 32 DSCP 1 groups defined in Table 2.8, 21 DSCPs have been standardized as follows: one for PHB EF, 12 for PHB AF, and 8 for CSCP. There are 11 DSCP 1 groups still available for other standards.
2.2.5.Example of Differentiated Services
We will look at an example of the Differentiated Service model and mechanism of operation. The architecture of Differentiated Service consists of two basic sets of functions:
Edge functions: include packet classification and traffic conditioning. At the inbound edge of the network, incoming packets are marked. In particular, the DS field in the packet header is set to a certain value. For example, in Figure 2.12, packets sent from H1 to H3 are marked at R1, while packets from H2 to H4 are marked at R2. The labels on the received packets identify the service class to which they belong. Different traffic classes receive different services in the core network. The RFC definition uses the term behavior aggregate rather than the term traffic class. After being marked, a packet can be forwarded immediately into the network, delayed for a period of time before being forwarded, or dropped. We will see that there are many factors that affect how a packet is marked, and whether it is forwarded immediately, delayed, or dropped.
Figure 2.12 DiffServ Example
Core functionality: When a DS-marked packet arrives at a Diffservcapable router, the packet is forwarded to the next router based on
Per-hop behavior is associated with packet classes. Per-hop behavior affects router buffers and the bandwidth shared between competing classes. An important principle of the Differentiated Service architecture is that a router's per-hop behavior is based only on the packet's marking or the class to which it belongs. Therefore, if packets sent from H1 to H3 as shown in the figure receive the same marking as packets from H2 to H4, then the network routers treat the packets exactly the same, regardless of whether the packet originated from H1 or H2. For example, R3 does not distinguish between packets from h1 and H2 when forwarding packets to R4. Therefore, the Differentiated Service architecture avoids the need to maintain router state about separate source-destination pairs, which is important for network scalability.
Chapter Conclusion
Chapter 2 has presented and clarified two main models of deploying and installing quality of service in IP networks. While the traditional best-effort model has many disadvantages, later models such as IntServ and DiffServ have partly solved the problems that best-effort could not solve. IntServ follows the direction of ensuring quality of service for each separate flow, it is built similar to the circuit switching model with the use of the RSVP resource reservation protocol. IntSer is suitable for services that require fixed bandwidth that is not shared such as VoIP services, multicast TV services. However, IntSer has disadvantages such as using a lot of network resources, low scalability and lack of flexibility. DiffServ was born with the idea of solving the disadvantages of the IntServ model.
DiffServ follows the direction of ensuring quality based on the principle of hop-by-hop behavior based on the priority of marked packets. The policy for different types of traffic is decided by the administrator and can be changed according to reality, so it is very flexible. DiffServ makes better use of network resources, avoiding idle bandwidth and processing capacity on routers. In addition, the DifServ model can be deployed on many independent domains, so the ability to expand the network becomes easy.
Chapter 3: METHODS TO ENSURE QoS FOR MULTIMEDIA COMMUNICATIONS
In packet-switched networks, different packet flows often have to share the transmission medium all the way to the destination station. To ensure the fair and efficient allocation of bandwidth to flows, appropriate serving mechanisms are required at network nodes, especially at gateways or routers, where many different data flows often pass through. The scheduler is responsible for serving packets of the selected flow and deciding which packet will be served next. Here, a flow is understood as a set of packets belonging to the same priority class, or originating from the same source, or having the same source and destination addresses, etc.
In normal state when there is no congestion, packets will be sent as soon as they are delivered. In case of congestion, if QoS assurance methods are not applied, prolonged congestion can cause packet drops, affecting service quality. In some cases, congestion is prolonged and widespread in the network, which can easily lead to the network being "frozen", or many packets being dropped, seriously affecting service quality.
Therefore, in this chapter, in sections 3.2 and 3.3, we introduce some typical network traffic load monitoring techniques to predict and prevent congestion before it occurs through the measure of dropping (removing) packets early when there are signs of impending congestion.
3.1. DropTail method
DropTail is a simple, traditional queue management method based on FIFO mechanism. All incoming packets are placed in the queue, when the queue is full, the later packets are dropped.
Due to its simplicity and ease of implementation, DropTail has been used for many years on Internet router systems. However, this algorithm has the following disadvantages:
− Cannot avoid the phenomenon of “Lock out”: Occurs when 1 or several traffic streams monopolize the queue, making packets of other connections unable to pass through the router. This phenomenon greatly affects reliable transmission protocols such as TCP. According to the anti-congestion algorithm, when locked out, the TCP connection stream will reduce the window size and reduce the packet transmission speed exponentially.
− Can cause Global Synchronization: This is the result of a severe “Lock out” phenomenon. Some neighboring routers have their queues monopolized by a number of connections, causing a series of other TCP connections to be unable to pass through and simultaneously reducing the transmission speed. After those monopolized connections are temporarily suspended,
Once the queue is cleared, it takes a considerable amount of time for TCP connections to return to their original speed.
− Full Queue phenomenon: Data transmitted on the Internet often has an explosion, packets arriving at the router are often in clusters rather than in turn. Therefore, the operating mechanism of DropTail makes the queue easily full for a long period of time, leading to the average delay time of large packets. To avoid this phenomenon, with DropTail, the only way is to increase the router's buffer, this method is very expensive and ineffective.
− No QoS guarantee: With the DropTail mechanism, there is no way to prioritize important packets to be transmitted through the router earlier when all are in the queue. Meanwhile, with multimedia communication, ensuring connection and stable speed is extremely important and the DropTail algorithm cannot satisfy.
The problem of choosing the buffer size of the routers in the network is to “absorb” short bursts of traffic without causing too much queuing delay. This is necessary in bursty data transmission. The queue size determines the size of the packet bursts (traffic spikes) that we want to be able to transmit without being dropped at the routers.
In IP-based application networks, packet dropping is an important mechanism for indirectly reporting congestion to end stations. A solution that prevents router queues from filling up while reducing the packet drop rate is called dynamic queue management.
3.2. Random elimination method – RED
3.2.1 Overview
RED (Random Early Detection of congestion; Random Early Drop) is one of the first AQM algorithms proposed in 1993 by Sally Floyd and Van Jacobson, two scientists at the Lawrence Berkeley Laboratory of the University of California, USA. Due to its outstanding advantages compared to previous queue management algorithms, RED has been widely installed and deployed on the Internet.
The most fundamental point of their work is that the most effective place to detect congestion and react to it is at the gateway or router.
Source entities (senders) can also do this by estimating end-to-end delay, throughput variability, or the rate of packet retransmissions due to drop. However, the sender and receiver view of a particular connection cannot tell which gateways on the network are congested, and cannot distinguish between propagation delay and queuing delay. Only the gateway has a true view of the state of the queue, the link share of the connections passing through it at any given time, and the quality of service requirements of the
traffic flows. The RED gateway monitors the average queue length, which detects early signs of impending congestion (average queue length exceeding a predetermined threshold) and reacts appropriately in one of two ways:
− Drop incoming packets with a certain probability, to indirectly inform the source of congestion, the source needs to reduce the transmission rate to keep the queue from filling up, maintaining the ability to absorb incoming traffic spikes.
− Mark “congestion” with a certain probability in the ECN field in the header of TCP packets to notify the source (the receiving entity will copy this bit into the acknowledgement packet).
Figure 3. 1 RED algorithm
The main goal of RED is to avoid congestion by keeping the average queue size within a sufficiently small and stable region, which also means keeping the queuing delay sufficiently small and stable. Achieving this goal also helps: avoid global synchronization, not resist bursty traffic flows (i.e. flows with low average throughput but high volatility), and maintain an upper bound on the average queue size even in the absence of cooperation from transport layer protocols.
To achieve the above goals, RED gateways must do the following:
− The first is to detect congestion early and react appropriately to keep the average queue size small enough to keep the network operating in the low latency, high throughput region, while still allowing the queue size to fluctuate within a certain range to absorb short-term fluctuations. As discussed above, the gateway is the most appropriate place to detect congestion and is also the most appropriate place to decide which specific connection to report congestion to.
− The second thing is to notify the source of congestion. This is done by marking and notifying the source to reduce traffic. Normally the RED gateway will randomly drop packets. However, if congestion
If congestion is detected before the queue is full, it should be combined with packet marking to signal congestion. The RED gateway has two options: drop or mark; where marking is done by marking the ECN field of the packet with a certain probability, to signal the source to reduce the traffic entering the network.
− An important goal that RED gateways need to achieve is to avoid global synchronization and not to resist traffic flows that have a sudden characteristic. Global synchronization occurs when all connections simultaneously reduce their transmission window size, leading to a severe drop in throughput at the same time. On the other hand, Drop Tail or Random Drop strategies are very sensitive to sudden flows; that is, the gateway queue will often overflow when packets from these flows arrive. To avoid these two phenomena, gateways can use special algorithms to detect congestion and decide which connections will be notified of congestion at the gateway. The RED gateway randomly selects incoming packets to mark; with this method, the probability of marking a packet from a particular connection is proportional to the connection's shared bandwidth at the gateway.
− Another goal is to control the average queue size even without cooperation from the source entities. This can be done by dropping packets when the average size exceeds an upper threshold (instead of marking it). This approach is necessary in cases where most connections have transmission times that are less than the round-trip time, or where the source entities are not able to reduce traffic in response to marking or dropping packets (such as UDP flows).
3.2.2 Algorithm
This section describes the algorithm for RED gateways. RED gateways calculate the average queue size using a low-pass filter. This average queue size is compared with two thresholds: minth and maxth. When the average queue size is less than the lower threshold, no incoming packets are marked or dropped; when the average queue size is greater than the upper threshold, all incoming packets are dropped. When the average queue size is between minth and maxth, each incoming packet is marked or dropped with a probability pa, where pa is a function of the average queue size avg; the probability of marking or dropping a packet for a particular connection is proportional to the bandwidth share of that connection at the gateway. The general algorithm for a RED gateway is described as follows: [5]
For each packet arrival
Caculate the average queue size avg If minth ≤ avg < maxth
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Applying Project-Based Learning to Organize Study Tours to the Hoa Lu Ancient Capital Cultural Heritage -
Applying MIKE 11 model to determine minimum flow on the main stream of Vu Gia - Thu Bon river and proposing maintenance solutions - 13
In the past, Vietnam did not have a set of criteria for assessing insurance companies. The handling was often based on each individual violation, not considering the overall situation of the insurance company. However, it is also recognized that assessing each criterion separately also has many potential risks. For example, an insurance company may have a solvency margin that is not within the warning threshold, calculated on the retained insurance premium level. But that insurance company itself repatriates a large part of the collected premiums abroad to an unqualified reinsurance company. When the risk occurs, the reinsurance company is not able to pay, so the original insurance company must pay all the responsibility to the insurance buyer, but if it has to pay the reinsurance part, it is very likely that the insurance company will also lose its ability to pay. Therefore, if only assessing the solvency part, it is not necessarily accurate for the insurance company, but there must be an overall assessment. The evaluation criteria should cover business performance indicators, liquidity indicators, capital indicators, and profit indicators.
In any monitoring method, it is necessary to indicate the position of the insurance company or the level of pure risk for each insurance company. The position of each insurance company is the result of the monitoring process. The thesis proposes to develop criteria for evaluating non-life insurance companies as follows:

- First of all, it is necessary to establish calculation weights for insurance companies: Identify factors affecting the financial situation of insurance companies, which factors have the most impact, and give weights to those factors;
- Insurance companies calculate and report the calculation results to the Ministry of Finance;
- The Ministry of Finance shall base on the reports of insurance companies and combine the monitoring results of the supervisory agency to classify insurance companies.
Develop 5 types of rankings and implementation solutions for each type as follows:
Type 1: are enterprises with good operating results, early warning indicators are all within the allowable range. For insurance enterprises and foreign branches ranked in type 1, perform:
+ Continue to consolidate and maintain business operations; research and expand business operations, open more branches based on the principles of efficiency and fair competition;
+ Continue to increase the use of information technology systems in business operations, management and administration; improve the quality of customer care services;
+ Strengthen internal control and internal audit.
Type 2: are enterprises whose early warning indicators are all within the allowable range but whose operating results are not good, and whose risk prevention indicators are only at an average level. For insurance enterprises and foreign branches ranked in type 2, the following must be implemented:
+ Develop and implement business plans focusing on strong market segments;
+ Streamline the operating system, cut down on operating and management costs;
+ Handling and recovering bad debts;
+ Increase capital; restructure investment portfolio towards limiting investment in risky assets, building and implementing effective reinsurance plans.
Type 3 : are businesses that are not profitable and are at risk of insolvency without risk prevention measures. For insurance companies and foreign branches classified as type 3, the following must be implemented:
+ Narrow down business operations and close unprofitable branches; limit business expansion;
+ Transfer one or several insurance operations;
+ Do not distribute profits to shareholders (members) contributing capital.
+ For insurance companies at risk of insolvency, follow the provisions in Clause 1 and Clause 2, Article 19 of Decree No. 46/2007/ND-CP. For foreign branches at risk of insolvency, follow the provisions in Clause 6, Article 19 of Decree No. 123/2011/ND-CP.
Type 4: are early warning indicators that are beyond the allowable level, with no risk prevention measures. For insurance companies and foreign branches ranked in type 4, the following must be implemented:
+ Conversion of business form, merger, acquisition by another organization;
+ For insurance companies and foreign branches that are at risk of insolvency, and after implementing measures still fail to restore solvency, they will be placed under special control. The Ministry of Finance has decided to establish a Solvency Control Board to apply measures to restore solvency according to the provisions of Article 80 of the Law on Insurance Business.
Type 5: after applying measures but still unable to restore solvency, the insurance company carries out bankruptcy procedures, the foreign branch carries out dissolution and closure procedures according to the provisions of law.
With the DNBH classification assessment method, supervisors can have a consistent assessment and handling method throughout the market.
The set of criteria for assessing insurance companies can be developed and applied from 2015. When the complete conversion to risk-based supervision is completed, this set of criteria will be rebuilt to match the calculation method of the new supervision method.
3.2.1.5. Moving from a minimum capital model to a risk-based capital (RBC) model
To implement risk-based supervision, in addition to regulating minimum capital, it is necessary to calculate capital based on risk. If only regulating minimum capital, the supervisory agency will provide the required capital level for insurance companies that do the most business. The reality is that there will be insurance companies that do not use all of that capital, if that insurance company only does basic business (for example, motor vehicles), the loss level is not too large, and the number of participants in the risk is large. These insurance companies can only use the capital for investment. In the current Vietnamese market, insurance companies mainly invest in the form of deposits. Regulating capital levels based on risk will help insurance companies use capital effectively.
Vietnam is calculating capital according to the minimum capital model, taking into account the risk-based capital level by stipulating that opening an additional branch requires an increase of VND 20 billion. However, these regulations are also approximate and do not have a clear basis for calculating capital needs when insurance companies deploy new types of business. Current regulations in Vietnam only focus on risks for insurance activities, while risks in other activities such as credit risk, market risk, and disaster risk
nature… has not been given due attention. It is recommended that the current insurance market supervisory agencies in Vietnam should provide a specific roadmap to transition to risk-based capital (RBC) supervision.
The regulation of capital levels based on risks is appropriate to the business operations of each insurance company; ensuring financial safety for insurance companies. To do this, it is necessary to classify types of risks, identify factors affecting capital risks. Develop risk assessment categories that the supervisory agency will monitor and the assessment level of each risk category. Currently, countries build from 4 to 8 categories. Based on the information conditions obtained from Vietnamese insurance companies, the thesis proposes to choose 6 risk categories, which are: insurance risk, business risk, liquidity risk, interest rate risk, investment risk, compliance risk. However, to calculate capital based on risks, only rely on the following 4 risks, which are risks with high risk of occurrence such as:
(1) Insurance risk (Including insurance price risk and reserve fund risk)
Insurance price risk : This risk level of non-life insurance companies in Vietnam is very high due to the use of unfair competitive measures such as: lowering fees, reducing deductibles, expanding insurance coverage; unprofessional insurance assessment procedures and methods; limited capacity of insurance assessment specialists; passivity in reinsurance,...
Insurance reserve risk : This risk arises from the inherent limitations of enterprises - the capacity of the calculation team, information technology system, ... even the business thinking in the management of insurance enterprises and the shortcomings of related management regulations. Insurance enterprises often choose the simple method of provisioning, making incomplete provisions for compensation reserves. This has made the provisioning of technical reserves between insurance enterprises arbitrary, according to the wishes of the enterprises and not unified. Incomplete provisioning is also a big risk for insurance enterprises.
(2) Business risk (corporate governance risk ): stemming from limitations in management capacity, incomplete and inconsistent systems, processes and internal control systems, this risk is high for Vietnamese non-life insurance companies.
( 3) Investment risks (including market risks and credit risks): Vietnam's financial market is still young, so risks arising from the unstable development of
market factors, investment environment, legal environment. In addition, there are limitations in capacity, experience and professionalism in investment activities of some enterprises themselves, so the risk potential for many enterprises is quite large.
Currently, credit institutions in Vietnam have low credit ratings. According to a recent announcement by banker of The Financial Times, Vietnam has 43 banks surveyed but only 11 banks are in the list of 1000. Of which, Vietinbank is ranked 362, Vietcombank is ranked 467, BIDV is ranked 522, Saigon Thuong Tin is ranked 777, Eximbank is ranked 802. Many banks have high levels of bad debt. Therefore, credit risk is also a risk for insurance companies because the investment structure of insurance companies focuses mainly on deposits at credit institutions.
(4) Liquidity risk : liquidity risk is governed by the above investment risk and the unstable development of related market factors, so it is still a major danger for many Vietnamese insurance companies, even though bank deposits account for a significant proportion in the asset structure of enterprises.
In fact, depending on the level of development of the market, each bloc such as the EU, Northern Europe, America, etc. has different calculation formulas depending on the risks considered as the main risks of that market. According to the general formula, the risk level is calculated based on the level of covariation of the square of the types of risks.
Proposed calculation formula:
RBC = √(R1 2 +R2 2 + R3 2 + R4 2 )
RBC refers to 4 main forms of risk, including:
+ R1: Insurance risk
+ R2: Business risk
+ R3: Investment risk
+ R4: Liquidity risk
The level of intervention depends on the RBC capital ratio (Current Capital/RBC) as follows:
- If above 150%: No intervention required;
- From 120 - 150%: Insurance companies must send reports to the supervisory agency;
- From 110 - 120%: Insurance companies must submit additional capital action plans to the supervisory agency;
- From 90 - 110%: The supervisory agency has the right to operate the enterprise;
- Below 90%: The supervisory agency is obliged to take over the management of the enterprise (level)
coercive degree).
In the initial stage, Vietnam should apply both minimum capital and risk-based capital because the risk-based capital calculation level in the initial stage may not be close to the risk level, due to the lack of data system of insurance companies in the past as well as information system to analyze the risk level, market factors, and the legal environment is still unstable. To ensure safety, both types of capital should be applied. When the market develops to a more stable stage, it may be necessary to apply only the risk-based capital level.
3.2.1.6. Calculation of Solvency Margin
Solvency margin is an important indicator for each insurance company when determining financial soundness. According to current international practice, there are 3 ways to calculate solvency margin as presented in chapter 1. Vietnam is currently implementing its own calculation method. Current regulations in Vietnam allow the net risk factor not to exceed 4:1 and the gross risk factor not to exceed 8:1. In other words, current regulations in Vietnam stipulate the maximum leverage ratio rather than the solvency regulation according to the 3 international approaches. Therefore, the proposed amendment is for the following reasons:
The maximum leverage requirement is not a solvency requirement. Maximum leverage limits potential risk but does not address the critical issue of the extent to which assets exceed liabilities and how that excess relates to overall risk. The relationship between assets and liabilities should be a direct measure of solvency, not a ratio of premiums to equity.
The net risk ratio and gross risk ratio stipulated in Decree 46/2007/ND-CP are high compared to international standards (2.5: 1). Therefore, Vietnam allows insurance companies to accept higher risks than the average of other countries. That will make the insurance buyer bear a higher risk level.
Instead of calculating risk weights for assets and liabilities to calculate the total minimum capital, Vietnam is determining the solvency margin of enterprises based on the discount of recognized assets when calculating the solvency margin according to predetermined coefficients. The discounting of asset values does not take into account the risk on the liability side.
The solvency requirement is essentially a requirement that assets exceed liabilities to a certain extent and will become larger as the debt level of the enterprise increases with the scale of the business. The minimum level at which assets exceed liabilities is called the margin.
Solvency. This concept reflects that the larger the debt, the higher the equity required to compensate for unforeseen fluctuations. The nature of insurance products is a guarantee, the equity scale corresponding to the debt scale is the guarantee for that guarantee. It is proposed, with current conditions in Vietnam, to move towards applying a solvency margin of 1, but with adjusted coefficients to suit Vietnam. When calculating the solvency margin, in addition to the retained premium factor, it is necessary to take into account the loss compensation reserve factor.
3.2.1.7. Develop monitoring indicators and early warning indicators
Insurance companies, like other businesses, must operate for profit. One of the market monitoring objectives of the supervisory agency for any business operating in any field is to focus on whether the financial capacity of the business is strong enough to withstand market shocks. Therefore, the supervisory agency needs a set of monitoring criteria that includes general assessment criteria that any business must have and criteria specific to each business activity, in this case, the insurance business.
The effectiveness of monitoring depends on the appropriateness of the indicators used, the standards for comparison and comparison, and the quality of information . Currently, Vietnam is applying the early warning indicator system according to Decision 153/2003/QD-BTC, however, this system has shortcomings as analyzed in Chapter 2.
The way other indicators are calculated has now changed due to changes in the accounting regime. For example, the provisioning under the accounting regime is not only calculated on retained insurance premiums but also on reinsurance premiums while the financial mechanism only requires provisioning on retained insurance premiums. The margin for each indicator currently applied according to the general margin of the US is not suitable for Vietnam.
The thesis proposes to amend and supplement the system of monitoring and early warning indicators for non-life insurance companies:
(1) Add evaluation criteria
+ ROA = Profit after tax / total assets
This ratio measures the profitability of each asset of the insurer. The assets of the insurer are formed from loans and equity, both of which are used to finance the operations of the insurer. The efficiency of capital investment
Profitability is expressed through ROA, the higher the ROA the better because the insurer is earning more money on less investment.
+ ROE = Net profit / equity
Return on investment is an important overall measure of financial performance for any organization. Low or negative return on investment over a period of time will certainly harm the financial health of the insurance company.
At the same time, the survival of the insurance industry depends on shareholders agreeing to invest capital in insurance companies. If they do not receive reasonable profits, especially considering the uncertainty of non-life insurance companies, over time they will withdraw their investment capital and the insurance industry will gradually disappear because there is a comparison between the insurance sector and other sectors to choose investment.
+ Leverage ratio = Total assets/Equity
+ Quick ratio = Cash and cash equivalents/total current liabilities
This ratio can be described as a useful indicator of the ability of the insurer to meet its financial obligations without prematurely maturing long-term investments or borrowing money.
(2) Determine the appropriate reference amplitude
Early warning indicators have provided a useful perspective to address emerging difficulties in the financial market. However, the reference ranges have not been suitable for Vietnam in recent times. For example, the total premium revenue over fund capital indicators have a reference range of <900%, the net premium revenue over fund capital indicator has a reference range of <300%. In practice, Vietnamese insurance companies do not exceed this reference limit because the US applies a risk-based capital model, while Vietnam applies a minimum capital model. According to the assessment of the Non-Life Management and Supervision Department, the revenue over fund capital indicator with the highest result is PJICO, which is only 480%, while some companies like Liberty have 1.75%. Therefore, it is necessary to research and propose a reference range suitable for the situation of the Vietnamese non-life insurance market so that the assessment efficiency from the early warning indicator system is better. To do this, we rely on market data from inception (20 years); calculate ratios for the monitored companies and then rank the companies on the basis of using about 10% of the initial ratio as the basis for the reference bands.

![Pre-tax Profit of Bidv Tien Giang in the Period 2011-2015
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zt2a3gsnon-credit services, joint stock commercial bank
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At that time, the Branch had to set aside a provision for credit risks, which reduced the Branchs income.
Chart 2.2. Pre-tax profit of BIDV Tien Giang in the period 2011-2015
Unit: Billion VND
140
120
100
80
60
40
20
0
63.3
80.34
89.29
110.08
131.99
2011 2012 2013 2014 2015
Profit before tax
(Source: Report on the implementation of the annual business plan of the General Planning Department of BIDV Tien Giang [24])
However, through chart 2.2, it can be seen that BIDV Tien Giangs profit is still increasing continuously, and its operating efficiency is currently leaking. This is a contribution of non-credit services, and this service segment will be increasingly focused on growth by BIDV Tien Giang to ensure the highest profit safety because credit activities have many potential risks. At the same time, focusing on developing non-credit services is consistent with one of the contents of restructuring the financial activities of credit institutions in the project Restructuring the system of credit institutions in the period 2011-2015 approved by the Prime Minister in Decision No. 254/QD-TTg dated March 1, 2012 [14]: Gradually shifting the business model of commercial banks towards reducing dependence on credit activities and increasing income from non-credit services.
2.2. Current status of non-credit service development at BIDV Tien Giang.
2.2.1. BIDV Tien Giang has deployed the development of non-credit services in recent times.
Along with the development of the Head Office, BIDV Tien Giangs products and services are constantly improved and deployed in a diverse manner to ensure provision for many different customer groups in the area: individual customers, corporate customers, and financial institutions. Typical services are as follows: Payment services, treasury services, guarantee services, card services, trade finance, other services: Western Union, insurance commissions, consulting services, foreign exchange derivatives trading, e-banking services,...
2.2.1.1. Payment services:
In accordance with the Prime Ministers Project to promote non-cash payments in Vietnam [15], banks in Tien Giang province have continuously developed payment services to reduce customers cash usage habits through card services and electronic banking services such as: salary payment through accounts, focusing on developing card acceptance points, developing multi-purpose cards, paying social insurance by transfer, paying bills through banks, etc.
Chart 2.3. Net income from payment services in the period 2011-2015
Unit: Million VND
6000
5000
4000
3000
2000
1000
0
3922 4065
4720 5084 5324
2011 2012 2013 2014 2015
Net income from payment services
(Source: Report on the implementation of the annual business plan of the General Planning Department of BIDV Tien Giang [24])
Along with the technological development of the entire system, BIDV Tien Giang has a payment system with a fairly stable transaction processing speed, bringing many conveniences to customers. The results of observing chart 2.3 show that the income from payment services that the Branch has achieved has grown over the years but the speed is not high and the products are not outstanding compared to other banks. Domestic payment products such as: Online bill payment, electricity bills, water bills, insurance premiums, cable TV bills, telecommunications fees, airline tickets, etc. bring many conveniences to customers. Regarding international payment, this is an indispensable activity for foreign economic activities, BIDV Tien Giang is providing international payment methods for small enterprises producing agriculture, aquatic food and seafood that have credit relationships with banks in industrial parks in Tien Giang province such as: money transfer, collection, L/C payment.
2.2.1.2. Treasury services:
BIDV Tien Giang always focuses on ensuring treasury safety and currency security, always complies with legal regulations, and minimizes risks in operations such as: counting and collecting money from customers, receiving and delivering internal transactions, collecting from the State Bank (SBV) or other credit institutions, receiving ATM funds, bundling money, etc. BIDV Tien Giangs treasury service management department is always fully equipped with modern machinery and equipment such as: money transport vehicles, fire prevention tools, money counters, money detectors, magnifying glasses, etc. to ensure absolute safety in treasury operations, immediately identifying real and fake money and other risks that may affect people and assets of the bank and customers. In addition, implementing regulation 2480/QC dated October 28, 2008 between the State Bank of Tien Giang province and the Provincial Police on coordination in the fight against counterfeit money, in the 3-year review of implementation, BIDV Tien Giang discovered, seized and submitted to the State Bank of Tien Giang province 475 banknotes of various denominations and was commended by the Provincial Police and the State Bank of Tien Giang province [17].
Chart 2.4. Net income from treasury services in the period 2011-2015
Unit: Million VND
350
300
250
200
150
100
50
0
105 122
309 289 279
2011 2012 2013 2014 2015
Net income from treasury services
(Source: Report on the implementation of the annual business plan of the General Planning Department of BIDV Tien Giang [24])
However, as shown in Figure 2.4, income from treasury operations is not high and fluctuates. Specifically, in the period 2011-2013, net income increased and increased most sharply in 2013, then in the period 2013-2015, there was a downward trend. This fluctuation is due to the fact that fees collected from treasury services are often very low and can even be waived to attract customers to use other services.
2.2.1.3. Guarantee and trade finance services:
BIDV Tien Giang, thanks to the advantages of the province and the favorable location of the Branch, has continuously focused on developing income from guarantee services and trade finance.
Chart 2.5. Net income from guarantee and trade finance services in the period 2011-2015
Unit: Million VND
14000
12000
10000
8000
6000
4000
2000
0
5193 5695
2742 3420
8889
3992
11604 12206
5143 5312
2011 2012 2013 2014 2015
Net income from guarantee services Net income from Trade Finance
(Source: Report on the implementation of the annual business plan of the General Planning Department of BIDV Tien Giang [24])
Through chart 2.5, we can see that BIDV Tien Giangs income from guarantee services and trade finance has grown over the years. The reason is: Among BIDV Tien Giangs corporate customers, the construction industry is the industry with the highest proportion of customers after the trading industry, this is a group of customers with potential to develop guarantee services. The second group of customers is corporate customers in the fields of agricultural production, livestock and seafood processing with high import and export turnover in the area.
are the target of trade finance development. In addition, BIDV Tien Giang also focuses on continuously developing these customer groups to increase revenue for many other products and services in the future.
2.2.1.4. Card and POS services:
As a service that BIDV Tien Giang has recently developed strongly, it can be said that this is a very potential market and has the ability to develop even more strongly in the future. Card services with outstanding advantages such as fast payment time, wide payment range, quite safe, effective and suitable for the integration trend and the Project to promote non-cash payments in Vietnam. Cards have become a modern and popular payment tool. BIDV Tien Giang early identified that developing card services is to expand the market to people in society, create capital mobilized from card-opened accounts, contribute to diversifying banking activities, enhance the image of the bank, bring the BIDV Tien Giang brand to people as quickly and easily as possible. BIDV Tien Giang is currently providing card types such as: credit cards (BIDV MasterCard Platinum, BIDV Visa Gold Precious, BIDV Visa Manchester United, BIDV Visa Classic), international debit cards (BIDV Ready Card, BIDV Manu Debit Card), domestic debit cards (BIDV Harmony Card, BIDV eTrans Card, BIDV Moving Card, BIDV-Lingo Co-branded Card, BIDV-Co.opmart Co-branded Card). These cards can be paid via POS/EDC or on the ATM system. In addition, with debit cards, customers can not only withdraw money via ATMs but also perform utilities such as mobile top-up, online payment, money transfer,... through electronic banking services.
In order to attract customers with card services, BIDV Tien Giang has continuously increased the installation of ATMs. As of December 31, 2015, BIDV Tien Giang has 23 ATMs combined with 7 ATMs in the same system of BIDV My Tho, so the number of ATMs is quite large, especially in the center of My Tho City, but is not yet fully present in the districts. Basic services on ATMs such as withdrawing money, checking balances, printing short statements,... BIDV ATMs accept cards from banks in the system.
Banknetvn and Smartlink, cards branded by international card organizations Union Pay (CUP), VISA, MasterCard and cards of banks in the Asian Payment Network. From here, cardholders can make bill payments for themselves or others at ATMs, by simply entering the subscriber number or customer code, booking code that service providers notify and make bill payments.
Chart 2.6. Net income from card services in the period 2011-2015
Unit: Million VND
3500
3000
2500
2000
1500
1000
500
0
687
1023
1547
2267
3104
2011 2012 2013 2014 2015
Net income from card services
(Source: Report on the implementation of the annual business plan of the General Planning Department of BIDV Tien Giang [24])
Through chart 2.6, it can be seen that BIDV Tien Giangs card service income is constantly growing because the Branch focuses on developing businesses operating in industrial parks, which are the source of customers for salary payment products, ATMs, BSMS. Specifically, there are companies such as Freeview, Quang Viet, Dai Thanh, which are businesses with a large number of card openings at the Branch, contributing to the increase in card service fees [25].
Table 2.6. Number of ATMs and POS machines in 2015 of some banks in Tien Giang area.
Unit: Machine
STT
Bank name
Number of ATMs
Cumulative number of ATM cards
POS machine
1
BIDV Tien Giang
23
97,095
22
2
BIDV My Tho
7
21,325
0
3
Agribank Tien Giang
29
115,743
77
4
Vietinbank Tien Giang
16
100,052
54
5
Dong A Tien Giang
26
97,536
11
6
Sacombank Tien Giang
24
88,513
27
7
Vietcombank Tien Giang
15
61,607
96
8
Vietinbank - Tay Tien Giang Branch
6
46,042
38
(Source: 2015 Banking Activity Data Report of the General and Internal Control Department of the Provincial State Bank [21])
Through table 2.6, the author finds that the number of ATMs of BIDV Tien Giang is not much, ranking fourth after Agribank Tien Giang, Dong A Tien Giang, Sacombank Tien Giang. The number of POS machines of BIDV Tien Giang is very small, only higher than Dong A Tien Giang and BIDV My Tho in the initial stages of merging the BIDV system. Besides, BIDV Tien Giang has a high number of cards increasing over the years (table 2.7) but the cumulative number of cards issued up to December 31, 2015 is still relatively low compared to Agribank, Vietcombank, Dong A (table 2.6).
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![Qos Assurance Methods for Multimedia Communications
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low. The EF PHB requires a sufficiently large number of output ports to provide low delay, low loss, and low jitter.
EF PHBs can be implemented if the output ports bandwidth is sufficiently large, combined with small buffer sizes and other network resources dedicated to EF packets, to allow the routers service rate for EF packets on an output port to exceed the arrival rate λ of packets at that port.
This means that packets with PHB EF are considered with a pre-allocated amount of output bandwidth and a priority that ensures minimum loss, minimum delay and minimum jitter before being put into operation.
PHB EF is suitable for channel simulation, leased line simulation, and real-time services such as voice, video without compromising on high loss, delay and jitter values.
Figure 2.10 Example of EF installation
Figure 2.10 shows an example of an EF PHB implementation. This is a simple priority queue scheduling technique. At the edges of the DS domain, EF packet traffic is prioritized according to the values agreed upon by the SLA. The EF queue in the figure needs to output packets at a rate higher than the packet arrival rate λ. To provide an EF PHB over an end-to-end DS domain, bandwidth at the output ports of the core routers needs to be allocated in advance to ensure the requirement μ > λ. This can be done by a pre-configured provisioning process. In the figure, EF packets are placed in the priority queue (the upper queue). With such a length, the queue can operate with μ > λ.
Since EF was primarily used for real-time services such as voice and video, and since real-time services use UDP instead of TCP, RED is generally
not suitable for EF queues because applications using UDP will not respond to random packet drop and RED will strip unnecessary packets.
2.2.4.2 Assured Forwarding (AF) PHB
PHB AF is defined by RFC 2597. The purpose of PHB AF is to deliver packets reliably and therefore delay and jitter are considered less important than packet loss. PHB AF is suitable for non-real-time services such as applications using TCP. PHB AF first defines four classes: AF1, AF2, AF3, AF4. For each of these AF classes, packets are then classified into three subclasses with three distinct priority levels.
Table 2.8 shows the four AF classes and 12 AF subclasses and the DSCP values for the 12 AF subclasses defined by RFC 2597. RFC 2597 also allows for more than three separate priority levels to be added for internal use. However, these separate priority levels will only have internal significance.
PHB Class
PHB Subclass
Package type
DSCP
AF4
AF41
Short
100010
AF42
Medium
100100
AF43
High
100110
AF3
AF31
Short
011010
AF32
Medium
011100
AF33
High
011110
AF2
AF21
Short
010010
AF22
Medium
010100
AF23
High
010110
AF1
AF11
Short
001010
AF12
Medium
001100
AF13
High
001110
Table 2.8 AF DSCPs
The AF PHB ensures that packets are forwarded with a high probability of delivery to the destination within the bounds of the rate agreed upon in an SLA. If AF traffic at an ingress port exceeds the pre-priority rate, which is considered non-compliant or “out of profile”, the excess packets will not be delivered to the destination with the same probability as the packets belonging to the defined traffic or “in profile” packets. When there is network congestion, the out of profile packets are dropped before the in profile packets are dropped.
When service levels are defined using AF classes, different quantity and quality between AF classes can be realized by allocating different amounts of bandwidth and buffer space to the four AF classes. Unlike
EF, most AF traffic is non-real-time traffic using TCP, and the RED queue management strategy is an AQM (Adaptive Queue Management) strategy suitable for use in AF PHBs. The four AF PHB layers can be implemented as four separate queues. The output port bandwidth is divided into four AF queues. For each AF queue, packets are marked with three “colors” corresponding to three separate priority levels.
In addition to the 32 DSCP 1 groups defined in Table 2.8, 21 DSCPs have been standardized as follows: one for PHB EF, 12 for PHB AF, and 8 for CSCP. There are 11 DSCP 1 groups still available for other standards.
2.2.5.Example of Differentiated Services
We will look at an example of the Differentiated Service model and mechanism of operation. The architecture of Differentiated Service consists of two basic sets of functions:
Edge functions: include packet classification and traffic conditioning. At the inbound edge of the network, incoming packets are marked. In particular, the DS field in the packet header is set to a certain value. For example, in Figure 2.12, packets sent from H1 to H3 are marked at R1, while packets from H2 to H4 are marked at R2. The labels on the received packets identify the service class to which they belong. Different traffic classes receive different services in the core network. The RFC definition uses the term behavior aggregate rather than the term traffic class. After being marked, a packet can be forwarded immediately into the network, delayed for a period of time before being forwarded, or dropped. We will see that there are many factors that affect how a packet is marked, and whether it is forwarded immediately, delayed, or dropped.
Figure 2.12 DiffServ Example
Core functionality: When a DS-marked packet arrives at a Diffservcapable router, the packet is forwarded to the next router based on
Per-hop behavior is associated with packet classes. Per-hop behavior affects router buffers and the bandwidth shared between competing classes. An important principle of the Differentiated Service architecture is that a routers per-hop behavior is based only on the packets marking or the class to which it belongs. Therefore, if packets sent from H1 to H3 as shown in the figure receive the same marking as packets from H2 to H4, then the network routers treat the packets exactly the same, regardless of whether the packet originated from H1 or H2. For example, R3 does not distinguish between packets from h1 and H2 when forwarding packets to R4. Therefore, the Differentiated Service architecture avoids the need to maintain router state about separate source-destination pairs, which is important for network scalability.
Chapter Conclusion
Chapter 2 has presented and clarified two main models of deploying and installing quality of service in IP networks. While the traditional best-effort model has many disadvantages, later models such as IntServ and DiffServ have partly solved the problems that best-effort could not solve. IntServ follows the direction of ensuring quality of service for each separate flow, it is built similar to the circuit switching model with the use of the RSVP resource reservation protocol. IntSer is suitable for services that require fixed bandwidth that is not shared such as VoIP services, multicast TV services. However, IntSer has disadvantages such as using a lot of network resources, low scalability and lack of flexibility. DiffServ was born with the idea of solving the disadvantages of the IntServ model.
DiffServ follows the direction of ensuring quality based on the principle of hop-by-hop behavior based on the priority of marked packets. The policy for different types of traffic is decided by the administrator and can be changed according to reality, so it is very flexible. DiffServ makes better use of network resources, avoiding idle bandwidth and processing capacity on routers. In addition, the DifServ model can be deployed on many independent domains, so the ability to expand the network becomes easy.
Chapter 3: METHODS TO ENSURE QoS FOR MULTIMEDIA COMMUNICATIONS
In packet-switched networks, different packet flows often have to share the transmission medium all the way to the destination station. To ensure the fair and efficient allocation of bandwidth to flows, appropriate serving mechanisms are required at network nodes, especially at gateways or routers, where many different data flows often pass through. The scheduler is responsible for serving packets of the selected flow and deciding which packet will be served next. Here, a flow is understood as a set of packets belonging to the same priority class, or originating from the same source, or having the same source and destination addresses, etc.
In normal state when there is no congestion, packets will be sent as soon as they are delivered. In case of congestion, if QoS assurance methods are not applied, prolonged congestion can cause packet drops, affecting service quality. In some cases, congestion is prolonged and widespread in the network, which can easily lead to the network being frozen, or many packets being dropped, seriously affecting service quality.
Therefore, in this chapter, in sections 3.2 and 3.3, we introduce some typical network traffic load monitoring techniques to predict and prevent congestion before it occurs through the measure of dropping (removing) packets early when there are signs of impending congestion.
3.1. DropTail method
DropTail is a simple, traditional queue management method based on FIFO mechanism. All incoming packets are placed in the queue, when the queue is full, the later packets are dropped.
Due to its simplicity and ease of implementation, DropTail has been used for many years on Internet router systems. However, this algorithm has the following disadvantages:
− Cannot avoid the phenomenon of “Lock out”: Occurs when 1 or several traffic streams monopolize the queue, making packets of other connections unable to pass through the router. This phenomenon greatly affects reliable transmission protocols such as TCP. According to the anti-congestion algorithm, when locked out, the TCP connection stream will reduce the window size and reduce the packet transmission speed exponentially.
− Can cause Global Synchronization: This is the result of a severe “Lock out” phenomenon. Some neighboring routers have their queues monopolized by a number of connections, causing a series of other TCP connections to be unable to pass through and simultaneously reducing the transmission speed. After those monopolized connections are temporarily suspended,
Once the queue is cleared, it takes a considerable amount of time for TCP connections to return to their original speed.
− Full Queue phenomenon: Data transmitted on the Internet often has an explosion, packets arriving at the router are often in clusters rather than in turn. Therefore, the operating mechanism of DropTail makes the queue easily full for a long period of time, leading to the average delay time of large packets. To avoid this phenomenon, with DropTail, the only way is to increase the routers buffer, this method is very expensive and ineffective.
− No QoS guarantee: With the DropTail mechanism, there is no way to prioritize important packets to be transmitted through the router earlier when all are in the queue. Meanwhile, with multimedia communication, ensuring connection and stable speed is extremely important and the DropTail algorithm cannot satisfy.
The problem of choosing the buffer size of the routers in the network is to “absorb” short bursts of traffic without causing too much queuing delay. This is necessary in bursty data transmission. The queue size determines the size of the packet bursts (traffic spikes) that we want to be able to transmit without being dropped at the routers.
In IP-based application networks, packet dropping is an important mechanism for indirectly reporting congestion to end stations. A solution that prevents router queues from filling up while reducing the packet drop rate is called dynamic queue management.
3.2. Random elimination method – RED
3.2.1 Overview
RED (Random Early Detection of congestion; Random Early Drop) is one of the first AQM algorithms proposed in 1993 by Sally Floyd and Van Jacobson, two scientists at the Lawrence Berkeley Laboratory of the University of California, USA. Due to its outstanding advantages compared to previous queue management algorithms, RED has been widely installed and deployed on the Internet.
The most fundamental point of their work is that the most effective place to detect congestion and react to it is at the gateway or router.
Source entities (senders) can also do this by estimating end-to-end delay, throughput variability, or the rate of packet retransmissions due to drop. However, the sender and receiver view of a particular connection cannot tell which gateways on the network are congested, and cannot distinguish between propagation delay and queuing delay. Only the gateway has a true view of the state of the queue, the link share of the connections passing through it at any given time, and the quality of service requirements of the
traffic flows. The RED gateway monitors the average queue length, which detects early signs of impending congestion (average queue length exceeding a predetermined threshold) and reacts appropriately in one of two ways:
− Drop incoming packets with a certain probability, to indirectly inform the source of congestion, the source needs to reduce the transmission rate to keep the queue from filling up, maintaining the ability to absorb incoming traffic spikes.
− Mark “congestion” with a certain probability in the ECN field in the header of TCP packets to notify the source (the receiving entity will copy this bit into the acknowledgement packet).
Figure 3. 1 RED algorithm
The main goal of RED is to avoid congestion by keeping the average queue size within a sufficiently small and stable region, which also means keeping the queuing delay sufficiently small and stable. Achieving this goal also helps: avoid global synchronization, not resist bursty traffic flows (i.e. flows with low average throughput but high volatility), and maintain an upper bound on the average queue size even in the absence of cooperation from transport layer protocols.
To achieve the above goals, RED gateways must do the following:
− The first is to detect congestion early and react appropriately to keep the average queue size small enough to keep the network operating in the low latency, high throughput region, while still allowing the queue size to fluctuate within a certain range to absorb short-term fluctuations. As discussed above, the gateway is the most appropriate place to detect congestion and is also the most appropriate place to decide which specific connection to report congestion to.
− The second thing is to notify the source of congestion. This is done by marking and notifying the source to reduce traffic. Normally the RED gateway will randomly drop packets. However, if congestion
If congestion is detected before the queue is full, it should be combined with packet marking to signal congestion. The RED gateway has two options: drop or mark; where marking is done by marking the ECN field of the packet with a certain probability, to signal the source to reduce the traffic entering the network.
− An important goal that RED gateways need to achieve is to avoid global synchronization and not to resist traffic flows that have a sudden characteristic. Global synchronization occurs when all connections simultaneously reduce their transmission window size, leading to a severe drop in throughput at the same time. On the other hand, Drop Tail or Random Drop strategies are very sensitive to sudden flows; that is, the gateway queue will often overflow when packets from these flows arrive. To avoid these two phenomena, gateways can use special algorithms to detect congestion and decide which connections will be notified of congestion at the gateway. The RED gateway randomly selects incoming packets to mark; with this method, the probability of marking a packet from a particular connection is proportional to the connections shared bandwidth at the gateway.
− Another goal is to control the average queue size even without cooperation from the source entities. This can be done by dropping packets when the average size exceeds an upper threshold (instead of marking it). This approach is necessary in cases where most connections have transmission times that are less than the round-trip time, or where the source entities are not able to reduce traffic in response to marking or dropping packets (such as UDP flows).
3.2.2 Algorithm
This section describes the algorithm for RED gateways. RED gateways calculate the average queue size using a low-pass filter. This average queue size is compared with two thresholds: minth and maxth. When the average queue size is less than the lower threshold, no incoming packets are marked or dropped; when the average queue size is greater than the upper threshold, all incoming packets are dropped. When the average queue size is between minth and maxth, each incoming packet is marked or dropped with a probability pa, where pa is a function of the average queue size avg; the probability of marking or dropping a packet for a particular connection is proportional to the bandwidth share of that connection at the gateway. The general algorithm for a RED gateway is described as follows: [5]
For each packet arrival
Caculate the average queue size avg If minth ≤ avg < maxth
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