TCP Explicit Congestion Notification

Table Of Contents

TCP Explicit Congestion Notification

TCP Explicit Congestion Notification

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The TCP Explicit Congestion Notification (ECN) feature provides a method for an intermediate router to notify the end hosts of impending network congestion. It also provides enhanced support for TCP sessions associated with applications that are sensitive to delay or packet loss including Telnet, web browsing, and transfer of audio and video data. The benefit of this feature is the reduction of delay and packet loss in data transmissions.

Configuration Information

Configuration information is included in the "Configuring TCP" module of the Cisco IOS IP Application Services Configuration Guide, Release 12.4T, at the following URL:

http://www.cisco.com/univercd/cc/td/doc/product/software/ios124/124tcg/tiapp_c/htiptcp.htm

The following sections provide information about this feature:

•TCP Explicit Congestion Notification

•Configuring TCP Performance Parameters

•Verifying TCP Performance Parameters

•Verifying the Configuration of TCP ECN: Example

For a complete list of features included in the "Configuring TCP" module, see the Feature Information Table located toward the end of the module.

Command Reference Information

Command reference information is included in the Cisco IOS IP Application Services Command Reference, Release 12.2SB, at the following URL:

http://www.cisco.com/univercd/cc/td/doc/product/software/ios122sb/cr/sbiap_r/index.htm

New or Modified Commands

The following commands are new or modified for this feature:

•debug ip tcp ecn

•ip tcp ecn

•show debugging

•show tcp

Any Internet Protocol (IP) addresses used in this document are not intended to be actual addresses. Any examples, command display output, and figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses in illustrative content is unintentional and coincidental.

© 2006 Cisco Systems, Inc. All rights reserved.