branch to make deposit transactions. However, in reality, the Branch flexibly adds a transaction method channel " receive money at home " through the Branch's staff for large customers, VIP customers when customers need to receive money at home to prioritize customers, to improve convenience for customers, maintain relationships with customers to maintain HDV sales.
* Physical factors
Transactions on the network environment: Scientific interface, easy to see, easy to understand; fast access speed; fast and accurate transaction processing; customer information security; The bank is responsible for handling incidents and technological risks for customers.
Transactions with ATMs: Always have money in the machine; money in full denomination; easy operation, easy to understand language; security guaranteed; make commitments and promptly handle technical problems; …
In addition to investing in equipment at transaction offices, ATMs, or POS... Vietinbank also invests in additional equipment to perform transaction features for customers using personal devices such as: phones, Ipads, Iphones... which can save time and costs for customers and help customers easily control their personal accounts and when problems arise, they can immediately contact the bank and solving those problems will become easier and faster.
Currently, the ATM system of Vietnamese banks in general and Vietinbank Binh Dinh branch in particular still has many shortcomings such as: ATM errors, online transactions often crash, run out of money, ... causing difficulties for customers, reducing customer confidence. At the same time, due to work pressure, due to management not being really strict, the interactive environment is not really "perfect" for customers. There are still complaints and grievances from customers during transactions with the bank, such as: Slow operations, errors in interest calculation, unprofessionalism, Therefore, Vietinbank Binh Dinh branch needs to regularly monitor and check the electronic distribution system such as: ATMs, POS machines, ... to detect and immediately fix problems to ensure these machines always operate 24/24 hours.
2.2.5. Communication policy, promotion of banking services
* Communication level: Communication, advertising and posting activities are assigned to specialized units for events and service advertising undertaken by the Communication Department, with the main forms being mass media such as television stations, local newspapers, posters, image promotion via the internet in many forms: Onsite, Support online, Public Relation (PR) online, printing banners, X-shaped stands hanging at transaction points, advertising on LED screens at branch offices and computer screens, advertising via electronic screens at transaction offices, ATM screens, machine screens, service advertising via customer emails, distributing service flyers... to social media applications (social networks) have opened up many ways to approach potential customers for banks today.
* Marketing work: Attention has been paid and thoroughly implemented to each officer in the HDV department, to find customers, contact customers directly to introduce products or through associated partners, socio-economic organizations in the province, to introduce products. According to the survey results, the rate of customers knowing about HDV products through bank staff introduction and consultation is not high (32% _ table 2.13), mainly customers know about the Branch and come by themselves or through referrals, proving that the branch is still passive in finding new customers.
* Promotional programs: Vietinbank Binh Dinh branch has implemented promotional programs when customers come to deposit money or save on occasions such as New Year's Eve, April 30th, holidays... during the year, and also has lucky draw programs or gift programs when customers come to deposit money at the branch.
* Customer care: customer service hotline is handled by the Customer Care Center - BIDV Contact Center via hotline 19009247 or 0422200588, or send an email to bidv247@bidv.com.vn, all customer comments will be answered by the Center's staff 24/7 anytime, anywhere with the motto "Dedicated sharing - Accumulating trust".
information”. In addition, the Branch regularly contacts customers (providing information and introducing new products and services, etc.), listening to customers' feedback. However, due to limited funding and the number of staff in the Customer Relations Department who have to take on many tasks, the organization of meetings with customers, monitoring and care is somewhat limited.
Table 2.9: Density of advertising and service promotion activities of Vietinbank Binh Dinh branch in the period 2015-2017
Work
Average density | Note | |
Post news and articles on newspapers and radio | 2.3 posts/month | Including both written and visual media |
Set identity image | 100% transaction points, ATM | Identification image of Vietinbank |
Flyers, posters | 1 batch/quarter | When there is a conference, there is a new product, Promotional program,… |
Customer Conference | 01 time/year | Combine gifts at the beginning of the year |
Gratitude program client | 01 time/year | Year-end gift combination |
Social charity activities | 1.5 times/quarter | Award scholarships, build charity houses, disaster relief… |
Maybe you are interested!
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Solutions to Perfect Marketing Policy in Capital Mobilization at Joint Stock Commercial Bank for Industry and Trade, Binh Dinh Branch in the Coming Time -
Perfecting marketing policy in capital mobilization at Vietnam Joint Stock Commercial Bank for Industry and Trade - Binh Dinh Branch - 13 -
Capital Mobilization Growth Rate of Vietnam's Banking System -
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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(Source: Accounting Department of Vietinbank Binh Dinh Branch)
In which, social networking applications are increasingly used by bank employees to expand relationships with the public on the internet environment, overcome the limitations of time and space, and also as a way to lead customers to approach and become familiar with electronic banking services. Currently, Vietinbank Binh Dinh branch has created accounts on social media such as: Google Plus, Twitter, YouTube ... to update customers on incentives, discounts, discounts, promotional programs as a new form of dissemination and approach to its image to customers. Penetrate social media. Bank employees who were previously familiar with sales targets on credit growth, ATM cards, international credit cards ... now have another interesting target: the target of the number of people "responding", sharing the same opinion with a specific product or with the bank's social media page.
In addition, the branch also combines promotional measures such as free card opening, fee reduction for students, fee reduction for businesses paying salaries through card accounts, lucky draw card opening program, saving to win cars, luxury motorbikes, modern TVs, cash rewards, gold... Normally, promotional activities are carried out on holidays, New Year, founding anniversaries or according to the general program of the Headquarters, so they are less innovative and new.
* Customer relations: along with a number of programs that every year the Branch cooperates with the Parent Bank (Head Office) to organize annual conferences, gratitude programs, congratulatory calls and send gifts to VIP customers who deposit over 2 billion VND/year and traditional customers (2 years or more) depositing from 1 billion or more, while regular customers only receive congratulatory messages, holiday greetings for birthdays, International Women's Day March 8, Teachers' Day November 20... specifically according to Table 2.11 as follows:
Table 2.10: Customer relationship activities of Vietinbank Binh Dinh branch in the period 2015-2017
Unit: Billion VND
Year
2015 | 2016 | 2017 | Rate of increase, decrease (%) | Average growth rate (%) | ||
2016/ | 2017/ | |||||
2015 | 2016 | |||||
Total number of participants | 1,856 | 1,927 | 2,032 | 3.83 | 5.45 | 4.64 |
Number of gifts | 1,912 | 2,041 | 2,133 | 6.75 | 4.51 | 5.63 |
Total cost | 3,021 | 3,306 | 3,583 | 9.43 | 8.38 | 8.91 |
(Source: Accounting Department of Vietinbank Binh Dinh Branch)
2.2.6. Capital mobilization results of Joint Stock Commercial Bank for Industry and Trade - Binh Dinh Branch
The period 2015-2017 is the period when the economy still faces many difficulties, the production and business activities of many enterprises, many large enterprises have not really recovered and stabilized. In that context, Vietinbank Binh Dinh branch has implemented many appropriate solutions, supporting customers to overcome difficulties, strongly promoting
Business activities achieved remarkable results through basic indicators.
Table 2.11 below:
Table 2.11: Performance results of Vietinbank Binh Dinh branch in the period 2015-2017
Unit: Billion VND
TT
Target | 2015 | 2016 | 2017 | Rate of increase, decrease (%) | Average increase and decrease speed army (%) | ||
2016/ 2015 | 2017/ 2016 | ||||||
1 | Total mobilized capital | 1,892 | 2,291 | 2,608 | 21.1 | 13.8 | 17.45 |
- | Average capital mobilization army 01 worker | 16.17 | 19.25 | 21.38 | 19.0 | 11.1 | 15.05 |
2 | Total outstanding debt | 2,236 | 2,644 | 3,935 | 18.2 | 48.8 | 33.5 |
- | Average loan head | 19.11 | 22.22 | 32.25 | 16.3 | 45.1 | 30.7 |
- | Bad debt ratio/total outstanding | 1.16% | 0.82% | 0.68% | -29.3 | -17.1 | -23.2 |
3 | Total income | 568.36 | 622.3 | 753.21 | 9.5 | 21.0 | 15.25 |
- | Income from operations credit | 349.6 | 391.92 | 463.37 | 12.1 | 18.2 | 15.15 |
- | Income from services bank, other income | 11.76 | 13.21 | 21.84 | 12.3 | 65.3 | 38.8 |
4 | Total cost | 553.01 | 577.53 | 704.7 | 4.4 | 22.0 | 13.2 |
5 | Profit | 15.35 | 44.77 | 40.51 | 191.7 | -9.5 | 91.1 |
(Source: Business Results Report of the General Department of Vietinbank Binh Dinh Branch) Capital mobilization is one of the main areas of operation of a commercial bank, and is an indicator used to evaluate the level of completion of the annual business tasks of the Branch. Determining the importance of capital mobilization, the Branch always focuses and pays great attention, offers positive solutions, approaches to mobilize capital from many sources of economic organizations and residents, bringing growth results.
Annually achieved high results, improving the branch's market share in the area.
Average growth rate of mobilized capital in the last 3 years
17.5%/year. By December 31, 2017, mobilized capital reached 2,608 billion VND, reaching 95% of the yearly plan, up 13.8% compared to 2016. The average mobilized capital per employee also increased significantly, from 16.7 billion to 21.38 billion/employee (up 28%).
In the context of many economic difficulties, businesses in Binh Dinh province are operating inefficiently, the banking system cannot avoid the general impact of the economy. However, with the orientation of closely following the market, complying with the direction and regulations of the Vietnam Joint Stock Commercial Bank for Industry and Trade, the regulations of the Industry, in the spirit of support, sharing and creating all favorable conditions for businesses and people to access bank capital. The average growth rate of outstanding loans in 3 years reached 26%/year. Outstanding loans to the economy on December 31, 2017 reached 3,935 billion VND, exceeding the plan, increasing 75.98% compared to 2015.
In 2015, the branch's profit only reached 15.35 billion VND, the average profit per employee was only 130 million VND/employee, but in 2017 it increased to 40.51 billion VND, reaching an average of 400 million VND/employee, the average profit growth rate in the period 2015-2017 reached over 88%. In 2017, Vietinbank Binh Dinh branch continued to make a profit, however, the profit decreased compared to 2016, showing that business efficiency was not high, there were many reasons, but the cost of paying interest on loans to the Head Office accounted for a large proportion of the total cost, which was an important reason.
While total lending and outstanding loans of Vietinbank Binh Dinh both increased sharply compared to the previous year (up 48.5%), the difference between income and expenses only increased by 8.3%. The reason for this situation is primarily due to the high average input interest rate, credit activities in 2017 had many fluctuations: Vietinbank Binh Dinh reduced lending interest rates for many programs to accompany businesses according to the policy of the Government and the Provincial People's Committee; some credit programs exposed risks such as the credit program under Decree 67 of the Government... so the risk provision cost is large. This shows that for commercial banks whose main market share is credit business, the risk is always high.
Service income reached 21.84 VND, accounting for only 2.9% of total income, extremely low.
is also small compared to the scale of operations of Vietinbank Binh Dinh. In an increasingly developing economy, this is a potential market that banks need to target to diversify risks and is also a way to maximize the exploitation of idle money sources in society.
Table 2.12: Capital mobilization results of Vietinbank-Binh Dinh by classification
2015-2017 period
Unit: Billion VND
TT
Target | 2015 | 2016 | 2017 | ||||
1 | By term | Quantity | Density (%) | Quantity | Density (%) | Quantity | Density (%) |
Non-term deposits | 458.30 | 24.22 | 502.40 | 21.93 | 647.50 | 24.83 | |
Short term deposits | 1,101.10 | 58.20 | 1,423.10 | 62.12 | 1,599.60 | 61.33 | |
Medium and long term deposits | 332.60 | 17.58 | 365.50 | 15.95 | 360.90 | 13.84 | |
2 | By economic sector | ||||||
Organizational deposits | 494.55 | 26.14 | 596.97 | 26.06 | 675.98 | 25.92 | |
Personal deposits | 1,397.45 | 73.86 | 1,694.03 | 73.94 | 1,932.02 | 74.08 | |
Total | 1,892 | 2,291 | 2,608 | ||||
(Source: Business Results Report of General Department of Vietinbank Binh Dinh branch)
In terms of term structure, Vietinbank Binh Dinh's medium and long-term capital mobilization still accounts for a low proportion and has decreased sharply compared to 2017. The proportion of medium and long-term capital mobilization decreased from 17.58% to 13.84%, non-term and short-term capital accounted for the majority with 86.16%, which limited the Branch's initiative in lending. This result is affected by many factors, including the psychological factor of customers expecting interest rates to increase, so they do not deposit medium and long-term capital but only deposit short-term capital to have the opportunity to switch to longer terms when market interest rates increase. In terms of capital mobilization structure, residential deposits account for over 70% and the trend remains stable over the years (73.86% in 2015, increasing to 74.08% in 2017).
As of December 31, 2017, Vietinbank Binh Dinh branch's mobilized capital reached VND 2,608 billion, an increase of 13.83% over the same period in 2016 and an increase of 38% over 2015. Vietinbank Binh Dinh branch's mobilized capital has continuously increased in scale, reaching an average annual growth rate of 17.5%.
2.3. Customer evaluation of marketing policy in capital mobilization at Joint Stock Commercial Bank for Industry and Trade - Binh Dinh Branch
2.3.1. General information of surveyed customers
Among the surveyed customers, there were 105 men, accounting for 56.22%, and 81 women, accounting for 43.78%. Men tend to participate in transactions more than women. Customers under 35 years old accounted for 45.41%, from 36 to 55 years old accounted for 37.3%, and over 55 years old accounted for only 17.3%. This basic information shows that the gender and age structure of customers participating in the survey is quite consistent with the reality at Vietinbank Binh Dinh branch. Specific details are shown in detail in the following table:
Table 2.13: Statistics of surveyed subjects
Information
Classify | Number (people) | Percentage | |
Sex | Male | 104 | 56.22 |
Female | 81 | 43.78 | |
Total | 185 | 100 | |
Age | From 18-23 | 23 | 12.43 |
From 23-35 | 61 | 32.97 | |
From 36-55 | 69 | 37.30 | |
Over 55 | 32 | 17.30 | |
Total | 185 | 100 |
(Source: 2017 survey data, Author's synthesis and analysis)
About customer age : People of different ages will have different psychology and needs and their perception of marketing activities of Vietinbank Binh Dinh branch will also be different. We need to learn and classify customers by age.





![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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