Bandwidth Management Systems

The increasing demands of multimedia and priority traffic on corporate intranets has ultimately led to the development of a new class of performance-optimization tools. These tools, which are usually referred to as bandwidth managers or packet shapers, permit the allocation of bandwidth in an IP network according to various application-performance criteria. In effect, these tools provide a relatively inexpensive method of implementing policy-based routing over IP networks without large-scale changes to network infrastructure or the installation of expensive special-purpose routers. These tools, combined with load-balanced servers and caching strategies, reduce congestion on networks, ensure the delivery of priority messages, and support real-time traffic (including packetized voice data).

IP bandwidth management solutions give network managers the tools to prioritize business-critical traffic over less-important traffic, such as e-mail, Web browsing, File Transfer Protocol (FTP) file transfers, and external push applications. The capability to prioritize traffic improves the performance of vital applications, increases the number of transactions per second, optimizes bandwidth usage, and improves user satisfaction.

Bandwidth managers employ a variety of traffic-control techniques including TCP rate control, queuing, and policy definition in order to ensure that essential traffic reaches its destination during periods of network congestion. The need for these capabilities depends on several factors, such as the following:

• The variety of traffic types that are run over an intranet or TCP/IP WAN service
• Whether certain traffic is of more value than other traffic
• Whether any traffic has delay characteristics that require it to be prioritized

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