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Abstract

Contents

Introduction

Today the pace of development of the telecommunications industry is one of the most rapid. Along with a reduction in the pace of growth of the client base of operators, an increase in traffic due to the introduction of new technologies and the growing share of services, IP-based technologies. Given these trends, telecom operators are introducing new services, which leads to a transition to multiservice telecommunications networks. This in turn imposes some restrictions on the operation of telecommunications networks. There is a need to implement Quality of Service (QoS), which for different classes of traffic are often not only different but also contradictory. To simultaneously provide different QoS requirements in connection required to implement traffic control system, which in turn must consider the characteristics of different classes of traffic and to ensure effective redistribution of network resources.

1. Theme urgency

Currently, people are all multi-service networks are more interested in services such as video conferencing, access to web-services. But the methodology for ensuring the quality of service requirements of heterogeneous traffic is not permitted until the end. To solve this problem, the introduction of classes of service for different types of traffic and traffic management system, which will provide the specified classes of service for different types of network traffic by reallocating resources.

At the moment the topic of traffic management is very relevant, unnecessarily so far there is no single approach to solving this problem. One of the options to ensure the effective transfer of traffic from the support options QoS (Quality of Service) is the technology of multi-protocol label switching MPLS (MultiProtocol Label Switching). This is accomplished through technology traffic engineering Traffic Engineering (TE) through the use of load balancing mechanisms for network resources, choosing the optimal route of the traffic, the use of back-up procedures and the distribution of network load balancing and traffic congestion avoidance mechanisms.

2. Goal and tasks of the research

The aim is to enhance the performance of IP-based networks through a more efficient allocation of resources, bandwidth communication channels.

Main tasks of the research:

  1. Consider the principle of technology MPLS;
  2. Analyze the MPLS network management system;
  3. Consider the model of balancing queues to support Traffic Engineering Queues;
  4. Analyze to model the work of balancing the queues.

Research object: IP-Network

Research subject: The method of traffic control in IP-based networks

Within the master's study is planned to develop a method of balancing traffic in IP-based networks using the technology of MPLS-TE models and balancing queues. This technique enables efficient use of network resources.

3. The principle of the technology MPLS.

MPLS (MultiProtocol Label Switching) – a technology fast packet switching in multi-protocol networks, based on the use of tags. MPLS is developed and marketed as a way to build high-speed IP-lines, but its scope is not limited to the IP, but applies to any traffic routed network protocol. The basis of the principle of exchange of MPLS labels [8]. Any transmission packet associated with a particular class of network layer (Forwarding Equivalence Class, FEC), each of which is identified by a particular label. The mark value is unique only for a section of the path between adjacent nodes in the network MPLS, called routers, switching on labels (Label Switching Router, LSR). Check carried in each packet, the method of its connection to the packet depends on the technology used by the link layer. Figure 2 shows the path of a packet MPLS network.

Path of a packet MPLS network.

Figure 2 – Path of a packet MPLS network
(animation: 5 frames, 5 cycles of repeating, 151 kilobytes)
(CE1, CE2– source routers and destination, P1, P2, PE1, PE2 – transit routers)

4.Traffic management in MPLS Network

When optimizing traffic management in networks MPLS (MultiProtocol Label Switching), the important role technology plays traffic engineering (Traffic Engineering, TE). The technology is based on the idea of traffic engineering balancing the use of heterogeneous network resources – information, buffer and channel. The effectiveness of technology Traffic Engineering by the fact that most network traffic management improved on its principles, confirmed by the Resource Reservation Protocol RSVP-TE and LDP-TE, routing protocols, IS-IS-TE, OSPF-TE. One of the most effective approach is based on balancing the queues on the principles of traffic engineering technology (Traffic Engineering Queues) [10, 11] for the queue management in MPLS-networks.

Condition (4) ensures that no packet loss on the network node under consideration. Condition (5) is introduced to prevent overloading of the link bandwidth that is allocated to a packet of a network node queue management process.

5.The formulation of the optimization problem for servicing queues on the node MPLS-enabled network Traffic Engineering Queues

As a rule, the smaller the length of the packet, the "quality" stream served as small packets transmitted real-time traffic, which is sensitive to delays. Flow with a higher priority must traditionally [12] maintained better than low priority traffic. As a function of the flow characteristics can use the following expression:

where v – some normalization factor to be smooth the difference values in order of priority and the packet length in bytes.[9]

If one queue serviced streams with different length and (or) the priority of the packet, then this expression is advisable to use their averaged value.

If the number exceeds the number of bursts generated by the traffic flow, the flow distribution problem by queue becomes trivial, due to the lack deficit queues.

Conclusion

Proposed a model of balancing the queues at the nodes MPLS-network. The novelty of the model is that it is in contrast to the previously known models take into account the characteristics of the technology Traffic Engineering Queues, aimed at ensuring a balanced load buffer resource – the queuing network node.

Further studies are aimed at developing methods of balancing traffic based on the use of MPLS technology and optimization models.

This master's work is not completed yet. Final completion: December 2013. The full text of the work and materials on the topic can be obtained from the author or his head after this date.

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