- Worship nature (sun, moon, water, rain, wind, thunder, lightning...), crops (squash, rice, corn, beans...), livestock (buffalo, cow, pig...).
- Worshiping totems (bird, fish, tree, buffalo totems...), worshiping ancestors (national ancestors, tutelary gods, ancestors, grandparents).
- Worship of reproduction: genitals and sexual activities.
- Worshiping the Mother Goddesses: the Goddesses, the Four Mother Goddesses (heavenly palace, earthly palace, music palace (upper mountains), water palace (mother goddess), the Lady of the land and Thien Yana...
- Worship national heroes, local heroes, people with great contributions to the people and the country: Saint Giong, Saint Tran, Tan Vien Son Thanh, Ba Trung, Ly Ong Trong...
Maybe you are interested!
-
The Spiritual Value of the Mother Goddess Worship Belief for the Cham Community -
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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Illustration of Linkage Forms of Textile and Garment Enterprises in Textile and Garment Industry in China -
Overview of the Economic, Social and Educational Situation of Dak Glong District, Dak Nong Province
From that worshipful consciousness, in communities, customs and rituals of nature worship, ancestor worship, Mother worship and fertility rituals are formed. These are very familiar rituals and customs to Vietnamese people all over the country. Each of these beliefs has its deep roots in the relationship between humans and those supernatural objects. For example, why do humans worship nature? Because in daily life and work, every hour and every day, nature is closely linked and controls the success - failure, good - bad, good - bad in human activities. It gives rise to fear or apprehension, admiration or worship, and from there people perceive nature as sacred, divine beings. People put nature on family altars or in temples. Nature becomes a symbol in worship beliefs, in the culture of each nation, in literature and art of many eras. It is also the common path for beliefs to permeate the culture or community life of many ethnic groups in the world, not just in Vietnam.
1.1.2. Overview of forms of belief

Vietnamese beliefs are expressed in many diverse and rich forms. Below are some common forms of beliefs in the spiritual life of Vietnamese people:
Fertility beliefs encompass a vast universality in the treasure trove of Vietnamese folk beliefs. For rice-growing agricultural residents, the symbols of yin and yang, earth and sky, mountains and water are the main factors that create the growth of all things, all blending together with natural vitality to survive and develop. In every era, people still have the desire to learn and grasp everything about the world around them. That practice has formed a diverse and rich belief system, including fertility beliefs, beliefs that express people's belief in the prayer for reproduction, development of the race, the wish for prosperous production, and bountiful harvests. Ancient people also believed that through intuition, sacred energy accumulated in nature or in each person has the ability to be transferred to livestock and crops. Therefore, fertility beliefs with many folk worship rituals are increasingly developing.
Fertility worship is an indigenous belief of agricultural countries. Fertility means many; Real means to grow and flourish. Fertility worship is expressed through the worship of reproduction and sexual intercourse. This belief originated very anciently, when people went from not understanding or misunderstanding the cause of reproduction to beginning to understand the origin of reproduction of all things and humans as the combination of male - female, male - female, yin - yang... That reproduction of all things makes life abundant, people gradually fill the earth, crowded and happy. Reproduction therefore becomes sacred, and discovering the exact cause of reproduction is a wonderful new discovery that people worship. From there, it is expressed in cultural activities in two ways: rituals of worshiping male and female genitals and worshiping sexual intercourse. That belief is expressed in signals and symbols: yin - yang; heaven - earth; round - square; even - odd; fruit - hole; Chung cake (Tét) - Giay cake; Areca mo - a pestle, mortar - pestle... These symbols have entered art through carvings of stone or wooden idols; present in games.
folk games such as tram, no nuong procession, phet playing, con throwing; entered folk literature with myths about male and female goddess couples such as Nu Oa - Tu Tuong, Ong Dung - Ba Da, Ong Duc - Mu Cai, Ong Thu Tha - Ba Thu Thien in which the genitals are described and exaggerated.
Ancestor worship is a type of traditional belief that is universal in our nation. “Vietnamese ancestor worship in a broad sense means worshiping four-level deities: Country (King Hung) - Village (village god, especially village god) - Clan (ancestor) - Ancestral family (3 generations or 5 generations). Or three levels: Country - Village - Family. Four-level deity worship is often seen in the Northern region, especially the Northern Delta, where Kinh people have settled for a long time. Three-level deity worship is often seen in areas where Kinh people have just reclaimed and established their lives, such as the mountainous regions of the North, the Central Highlands and some parts of the South” [21, p. 39]. Ancestors in a narrow sense are people of the same bloodline, such as father, mother, grandfather, grandmother, great-grandfather, great-great-grandfather... who gave birth to us: Humans have ancestors/ Like trees have roots, like rivers have sources.
Ancestor worship has become a traditional custom, holding a very special position in the spiritual life of the Vietnamese people, and is one of the elements that create the national cultural identity. The belief in ancestor worship is very simple: believing that one's ancestors are sacred, they have passed away but still live with their descendants, they bless their descendants when they encounter disasters and difficulties; they rejoice when their descendants are lucky, encourage their descendants when they encounter good things and also reprimand their descendants when they do sinful things...
This belief was formed with the great role of Confucianism. From the foundation, Confucianism's rational concept of metaphysics is to recognize the existence of souls and spirits, but does not focus on thinking about them, respecting spirits and keeping them at a distance. However, when it comes to daily life, the dead are worshiped as living people (death is like birth) , that is, to consider the dead as still present in front of us with full consciousness and feelings of the living and especially with the ability to do many things.
which the living are limited. The highest form of ancestor worship is that the representatives of Confucianism, or using Confucianism as the basis for building a system of ruling power, advocated honoring those who had meritorious deeds and virtues while alive by granting posthumous names, solemn ceremonies during funerals, and giving money and fields for their descendants to worship. It cannot be said that this was a political trick to buy the loyalty of the subjects, but it must be thought that the court itself also shared a belief that the souls of the subjects were always by the king's side to help him as they were when he was alive.
When talking about Confucianism, we must talk about filial piety. Children worship their parents not only while they are alive, but even when a high-ranking official in the royal court has a parent in mourning, he must ask for leave to mourn, sometimes even building a hut next to the grave to be close to the deceased parent's spirit. Nowadays, we consider it old-fashioned because we only look at the phenomenon; but in fact, it is also seen as very similar to the origin of the ghost worship custom of some tribes still living recently in the highlands or plateaus, when a relative dies, they are placed in a coffin made from a hollowed-out tree trunk, placed in the corner of the house, so that when they come in and out morning and night, they are still as close as when they were alive. A long time later, they are buried.
The concept that the dead go to another world and still live as they did when they were alive, although their status may change, so relatives must take care of the deceased so that life in the new world is not difficult or lacking. Burial is therefore a universal practice not only among the Vietnamese people, but also among many other peoples in the world since ancient times and still exists today, although there have been some changes in details. With the characteristics of polytheistic agricultural residents, Vietnamese families often worship many gods. Besides worshiping ancestors and Buddha, people also worship their Aunts and Uncles, who are relatives who died young or died at sacred hours.
Most Vietnamese families worship their grandparents and ancestors. Ancestor worship at home is usually carried out year-round, originating from the concept of
Although they have passed away, their souls are always with their descendants. They not only worship on important occasions such as funerals, death anniversaries, weddings... or on holidays such as Lunar New Year, Thanh Minh, Han Thuc, Doan Ngo... on Soc (first day of the month) and Vong (full moon) days according to the lunar cycle, but their descendants also respectfully inform them of all their joys and sorrows: birth, illness, exams, passing exams, lawsuits, disagreements, marriage... Descendants respectfully invite them to enjoy the first fruits of the season, and to thank their ancestors when they have good fortune and luck. It can be said that in the minds of the living, ancestors are immortal. Vietnamese people burn incense and perform ceremonies to worship their ancestors to report and ask for their blessings, or to express gratitude when work is successful. The nature of Vietnamese ancestor worship comes from the belief that the living and the dead are closely connected and support each other. Descendants visit and pray to their ancestors. Ancestors protect and guide future generations, so the death anniversary is to carry out the exchange between the positive and negative whistles.
Nowadays, our people's lives have improved significantly, most families have upgraded their houses. Thanks to that, the space for ancestor worship has also become more spacious and diverse. The ancestral altar is always placed in the highest, cleanest and most solemn place in the house (the middle room for a one-story house, the top floor for a multi-story house). In some families, the altar position is arranged according to regulations, for example, the Saint Master is worshiped in the corner of the house, the Patriarch is worshiped in the yard, the Lady and the Manh are worshiped on the lower side of the ancestral altar... Among the gods worshiped at home, there is usually no god arranged on the same level as the ancestors.
In general, every family altar has the following main worship items: tablet, incense bowl, lamp plate, flower vase, wine cup, fruit tray, etc. In ordinary families, worship items are often made of wood or porcelain, while in wealthy families, worship items are often made of bronze. The ancestral altar of the eldest branch is more complicated than the second branch, the eldest branch is more complicated than the second branch, the second child's family, the youngest child only worships in memory, so the altar arrangement is also simpler than the eldest child's.
In addition, because of the need to make a living, many families have to migrate to work elsewhere, but they still worship their ancestors and their altars are called ancestral altars. Ancestral altars are a type of altar that people who live far from their hometowns and have little opportunity to return to their eldest son's house on New Year's Eve and death anniversaries set up. In the past, ancestral altars were not a major custom because most people lived and made a living in their hometowns, with only a few special cases called "biet quan" and "li huong". Nowadays, ancestral altars are used quite commonly because the rate of people living and working far from their hometowns is increasing.
Ancestor worship has simple and practical content, not as extreme as many other religions. Therefore, it is easily secularized to become a way of life, a custom, deeply rooted in the subconscious of each person. By worshiping ancestors, the previous generation sets an example for the next generation not only because of their responsibility to their parents but also to educate their children and grandchildren to pass on their lineage. It is also a reminder of the origin: with the morality of "remembering the source of water" , ancestor worship is sincerely derived from filial piety and gratitude, which has been deeply ingrained in the subconscious of each person since childhood: A tree has roots to grow green branches / Water has a source to have wide seas and deep rivers / Where do people come from? / There is a father, there is a mother, then there is me.
Over the centuries, the way and concept of ancestor worship of Vietnamese people in general and Hung Yen people in particular have changed a lot, but the greatest meaning remains the same: considering ancestor worship as one of the ethical principles of being human, a form of expressing filial piety and gratitude of descendants towards their parents.
Among the forms of belief, the belief in worshipping the village's tutelary god originated from China and was introduced to Vietnam during the period of Chinese domination. However, because the scale and structure of ancient Chinese villages are different from those of ancient Vietnamese villages, the belief in worshipping the tutelary god of ancient Vietnamese villages is also different from that of ancient Chinese villages. When speaking of
As for Thanh Hoang, we can understand that it is a name from the Chinese period, referring to a guardian deity, but protecting a city or citadel, because "Thanh" is a rampart and "Hoang" is a deep moat surrounding the rampart. Thanh Hoang in Vietnam is Thanh Hoang of the village, the guardian deity of the village, often associated with a communal house. Thanh Hoang of ancient Vietnamese villages is a person - according to legend - who has contributed to the people and the country in the resistance wars against foreign invaders, or a person who has contributed to founding the village, has contributed to teaching a certain profession to the villagers, or is a good mandarin (and some evil gods - but this number is not many).
Many villages worship Thanh Hoang, which is actually a natural power (such as river god, mountain god, thunder god, lightning god, cloud god, rain god); some villages worship historical figures as Thanh Hoang of their village, who are national heroes, who have contributed to repelling foreign invaders and regaining independence for the nation, such as: Ba Trung, Ba Trieu, Le Hoan, Duong Dinh Nghe, Le Van Thinh, To Hien Thanh, Ly Thuong Kiet, Tran Nhat Duat... Some villages worship Northern mandarins who once ruled our country as Thanh Hoang such as: Trieu Da, Si Nhiep, Cao Bien, Dao Hoang...
In the early period, Thanh Hoang was worshiped in temples (or shrines). Later, he was worshiped in both temples and the village communal house's harem. Because it was where Thanh Hoang resided, not everyone could freely come to the temple or shrine and the village communal house's harem; on the other hand, worshiping Thanh Hoang was a very important matter for the village and had to be done every day. Therefore, the village had to have a person in charge of the work. That person was Mr. Dam (also known as Cai Dam, Quan Dam). Mr. Dam enjoyed some rights stipulated by the village (such as being allowed to cultivate a certain area of rice fields to serve the worship of Thanh Hoang...), but he also had to follow some very strict taboos that if violated, would be severely punished by the village (such as during the entire time he was Mr. Dam, he was not allowed to be close to his wife, not allowed to touch unclean things, not allowed to go outside barefoot, not allowed to have a bare head, not allowed to attend funerals and not allowed to eat at funerals...).
The village's Thanh Hoang worship ceremony is a series of very strict village regulations, from the selection of the main celebrant, assistant celebrant, the eastern and western celebrants, to the movements, gestures, clothing... of those participating in the ceremony and the order of these people's movements during the ceremony. The village also regulates how many movements there are in the ceremony, starting from the "Khoi chinh co" section to "Te tat", what sentences the eastern celebrant chants, what sentences the main celebrant chants, where each position in the ceremony stands... All of these are carefully recorded in the village's ritual.
After the Procession and Sacrifice Ceremony of the Thanh Hoang, there are competitions, performances, and folk games. The competitions, performances, and folk games in the festival always have content describing the history or achievements of the Thanh Hoang. The locations of the processions, sacrifices, and performances are the communal houses and temples (or shrines) of the village: Each village's bell is rung by the village / Each village's Saint is worshiped by the village .
In addition to the above forms of belief, Mother worship also plays a great role in forming the rich belief system of the nation. Vietnamese Mother worship is an indigenous belief with foreign influences from Taoism, a belief that worships Mother as an idol with the power to reproduce, protect and shelter people. The belief that has been gendered in the image of the Mother is where Vietnamese women have placed their aspirations for liberation from the prejudices and constraints of the harsh feudal Confucian society.
Through the forms of belief, Vietnamese people have expressed their views on human beings, on the relationship between humans and nature and society. In the Fertility belief, the philosophy of yin and yang harmony is expressed, and at the same time, the relationship between humans and nature is also expressed. It is not a vulgar phenomenon but the eternal desire for food and clothing of the residents who always have to "look to the sky, look to the water, look to the clouds" to do agriculture;



![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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