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Abstract

When the abstract was writing this master's work was not complete yet. Final completion: june 2019. Full text of work and materials on the topic can be obtained from the website after this date.

Content

Introduction

A modern alternative to building multiple information networks is the creation of a multi-service network that should ensure the transfer of all necessary types of information through a single infrastructure. Multiservice networks provide reduction of expenses for communication channels, administration and maintenance of the network operability, as well as provide the possibility of carrying out a single administrative and technical policy in the field of information exchange.

The main feature of the corporate network is its reliability, security and versatility. Also the improvement of management methods, the automation of business processes and the optimization of expenditures on the information arrangement of the enterprise play an important role. All this can ensure the introduction of a new multi-service network in the enterprise.

1. Theme urgency

Nowadays, when the use of various telecommunication services is spreading, it becomes necessary to develop multiservice networks with the integration of services for enterprises of various sizes.

The growing popularity of multiservice communication networks has been one of the most noticeable trends in the telecommunications services market lately. The services of such a network are intended primarily for companies focused on intensive business development, cost optimization, automation of business processes, modern management techniques and information security. The most effective use of multiservice networks can be found in traditional telecommunications operators, which thus significantly expand the range of services provided. For the corporate market, combining all remote departments into a single multiservice network increases the efficiency of information exchange substantially, ensuring the availability of data at any time. Thanks to the ability to share large amounts of data between offices, one can arrange conference calls and hold video conferences with remote offices. All this accelerates the reaction to the changes that occur in the company, and provides optimal control of all processes in real time.

Thus, the calculation of the bandwidth of the communication channel of a multiservice corporate network in our time is quite important due to the increasing popularity of networks with the integration of services in the modern telecommunications market.

2. Goal and tasks of the research

The aim of the work is to study the capacity of the communication channel at an enterprise and improve it in the future.

To achieve this goal, the following tasks were solved in this piece of work:

  1. Various mechanisms of bandwidth control were considered.
  2. The probabilistic characteristics of IP-traffic of external channels of the enterprise network were analyzed.
  3. Method for improving the network at the enterprise was suggested.

3. Ideas to improve the functioning of multi-service networks and their implementation

Multiplicity of information traffic in the corporate network requires a special approach to its distribution through communication channels. That is, depending on the quality of service requirements, one can book a bandwidth for individual services. This is necessary for maximum optimization of communication quality and for optimal channel loading.

In order to get acquainted in detail with the features of various information flows, it is necessary to analyze them from the point of view of the teletraffic theory. In the future, such an approach implies a more convenient control of the quality of the services provided, which is important.

The laws of distribution of some of event streams that occur in telecommunication networks will help to get closer to solving the problem of optimal network load.

To conduct research, it is necessary to have a platform. As such, the Central Republican Bank banking network was taken. The main feature of the corporate banking network is its reliability and security, because we are talking about money of individuals and legal entities. Also, the improvement of management methods, the automation of business processes and the optimization of costs for the information arrangement of the enterprise play a significant role.

4. Existing bandwidth management mechanisms.

One of the distinguishing features of today is the growth of the amount of information and, accordingly, the cost of its transmission and processing. At that, multimedia occupies an increasingly important place in data traffic, and the integration of Web technologies into the business processes of companies leads to an exponential increase in the amount of data transmitted through information channels. The capacity of information systems designed for a linear development scheme, unfortunately, becomes a bottleneck that may not only significantly reduce the pace of development, but also jeopardizes the efficiency of the entire company.

To improve network utilization to the maximum possible level, bandwidth control mechanisms are used. Depending on the information needs of the enterprise and the design features of a network, various mechanisms are used

4.1. Bandwidth accelerator

Today, many companies inevitably face the need to increase the capacity of their network or leased communication channels. If the communication channel is rented and it is impossible to change it, a reasonable solution would be to use bandwidth optimizers (or accelerators). Recently, devices of this type are also called universal multiplexers, although the essence does not change: they connect to the gap between the serial port of the router and the channel-forming equipment (from both ends of the channel) and perform dynamic traffic compression (data, voice, faxes, LAN traffic (local area network)), as well as some other functions.

The advantage of accelerators, unlike, for example, caching web-traffic, is that they adapt to different types of IP-traffic and provide, depending on the type of user application, increasing network bandwidth by 2-4 or more times. In addition, they provide header compression for VoIP traffic (voice over IP) without using the processor resources of the routers. Dynamic monitoring of the state of a paired device allows switching on and off the power supply on it without dropping the channel with remote offices, and after turning on the power supply, traffic compression is automatically restored.

The basic requirements for such devices are as follows: accelerators should be easily installed; automatically determine the protocols that are used, having a similar device at the remote end is necessary, too. They also support Frame Relay (and Frame Relay +) technology, which allows connecting several remote offices (branches) to the center. For example, it is very profitable to use this technology in a network that unites remote offices of an enterprise where automated workplaces that work with the same application (for example, an enterprise resource planning system) are installed. However, less regular traffic can also be optimized.

Accelerators are practically the only solution to communication problems precisely in those cases when there is no possibility of increasing physical speed in existing communication channels with a bandwidth insufficient for user-targeted applications.

4.2. Shaper

Also, quite often there is a need to limit incoming and outgoing Internet traffic. One of the tools that help in resolving this issue is the shaper. Shaping implies limiting the bandwidth of the channel for an individual network node below the technical capabilities of the channel to the node. Shaping is usually used as a means of limiting the maximum consumption of traffic by a network node.

The shaping algorithm for networks working with packets (frames or other PDUs (protocol data units)) of data is usually used to create a queue of packages from the client. Per unit of time, packages with a total amount of no more than N bytes are passed (where N is a limit). If the amount of data transferred exceeds the bandwidth allocated to the client and the queue is full, the excess packages are not accepted. Due to the non-zero size of the queue at the beginning of the connection, it is possible to temporarily exceed the speed limit. In the case of QoS support, the packages from the queue are not selected sequentially, but in accordance with the marks of urgency of delivery.

Shaper can:

Shaper cannot:

It is not recommended to use shapers in the following cases:

4.3. Traffic prioritization service

If the network is constantly overloaded, one can implement a prioritization service, which, according to the settings, will allow important traffic to flow ahead, and the slightest prioritization traffic will be folded back when overloaded. If the situation with package loss is not acceptable at all, it is necessary to increase the network bandwidth. However, with the random nature of network overloads, switching to fast network technologies is not worth it; in this case, it is still necessary to introduce the traffic prioritization service that allows for a more uniform network load.

Many manufacturers have already developed ways and means to prioritize traffic on Ethernet networks, but their support is limited only to the products of these manufacturers. With the advent of high-bandwidth requirements, the need for compatible prioritization services from different manufacturers has become very urgent. The degree of prioritization importance is proportional to the level of competition of network bandwidth of data transmission channels.

Conclusion

In this research work, the main trends in the market of telecommunication services related to the introduction of multi-service networks in enterprises were considered. The main tasks in the design and configuration of such networks in practice were analyzed. A description of the most common bandwidth control mechanisms was also given:

Their features, advantages and disadvantages were considered.

References

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