flow routing

Rather than routing individual packets, a flow router observes and evaluates flows to gather statistics, including source, destination, amount of traffic "in flight," and stream duration. A flow is a single meaningful end-to-end activity over the network. This evaluation permits the router to prioritize traffic, deliver on quality of service (QoS) requirements, and keep flows from consuming more than some pre-allotted portion of network resources.

A flow router evaluates traffic flows in real time, based on an ID, route, time of receipt and rate of flow, to keep streaming traffic moving as quickly as possible. By contrast, conventional (Layer 3) IP routing does not differentiate between packets. Conventional routing uses a best-effort technique to ensure delivery of incoming traffic to the proper destination on a packet-by-packet basis, and is not sensitive to timing and data rate requirements for streaming data such as voice, video, multimedia and IPTV.

Industry analysts indicate that high-end conventional routers can achieve many of the same advantages touted for flow routing using ancillary queuing, deep-packet inspection, rate shaping and policing, and selective packet discard methods. Nevertheless, flow routing's unique ability to accommodate streaming data types makes it interesting and potentially valuable, especially for networks where such data consumes an appreciable portion of overall bandwidth and resources.

Dr. Lawrence G. Roberts (founder of Anagran and one of the creators of the ARPANET), developed Anagran's flow-based router over a period of seven years at that company and his previous start-up, Caspian.

Read more about flow routing: - Dr. Robert's paper, 'The Next Generation of IP – Flow Routing,' is available online. - Network World reports that 'Net pioneer Roberts touts Fast Flow Routing.'

Do you have something to add to this definition? Let us know. Send your comments to techterms@whatis.com

Digg This!     StumbleUpon     Del.icio.us

RELATED CONTENT Q&A: Nortel's data networking chief discusses the future Nortel VP of Data Solutions John McHugh talks about the viability of his company's data networking business. Nortel routers and switches may go to buyer of telephony business Do your Nortel routers and switches have a future or will they be lost in the shuffle as telephony gets the spotlight? 3Com hopes to win enterprise networking customers with global H3C push With its H3C brand, 3Com hopes to win back long-lost enterprise networking customers.

RELATED GLOSSARY TERMS Terms from Whatis.com − the technology online dictionary core router  (SearchNetworking.com) edge router  (SearchNetworking.com)