ISR research accomplishments

Frame relay network planning tool
US Patent 5,940,373    Aug. 17, 1999

Accomplishment

The need for the tool. Frame Relay (FR) is a high-speed, connection-oriented data transfer service. It uses permanent virtual connections (PVCs) to establish logical connections between customer locations to provide higher access speeds and less delay than traditional packet-switched technologies. Because frame relay networks are complex and expensive, their design must be cost-effective, reliable and have sufficient capacity to meet current and expected customer demand while ensuring economical use of capital resources.

One of the most pressing problems with frame relay networks stems from rapid growth and the lack of network planning tools. The majority of the engineering is done on a reactive rather than a proactive basis. The solution to the problem is more complex than merely adding a trunk or trunks to the network path--a network planning tool is needed to assist the engineer in planning and growing a network in a methodical fashion.

What does the tool accomplish?

This network planning tool:

• Analyzes the status of the current network, evaluates the condition of any user-defined configuration, and optimizes the expansion of the network based on demand and costs;
• Ensures that the network is cost effective, reliable and has sufficient capacity to meet current and expected customer demand;
• Optimizes the frame relay network based on customer demand, equipment used, and the existing network configuration;
• Recommends the optimal locations of new switches and backhaul locations where the user has determined they might be allowed;
• Recommends the configurations of existing switched (e.g. how many access cards to add) and the placement of new trunks;
• Includes a graphical user interface that allows the user to easily input required data, perform network optimization and what-if analysis, and display the results through menus, tables and graphical displays; and
• Can interface with existing database systems to obtain current network data directly without user entry.

The tool uses a heuristic approach that attempts to route a path for a given demand in a reasonable time. It attempts to optimize the network configuration for the given demand by a sequence of network configuration changes. After each change, an attempt is made to route the demand, with minimal cost, until all demand is routed. The network changes made by the program include (in order of priority) upgrading a link, adding a link, upgrading a switch, and adding a switch. When this process is completed a survivability test is run to ensure that the network configured by the tool is survivable.

Research team

Steve Y. Chiu (Louisville, Colo.)
Subramanian Raghavan (Robert H. Smith School of Business)
Ronald L. Hansen (Louisville, Colo.)
Jiyang Xu (Superior, Colo.)

US West, Inc., Denver
MediaOne Group, Inc., Englewood, Colo.

For more information

View this patent at the | Patent Trademark Office | IBM Intellectual Property Network |