Cisco Systems 78-11741-02 Setting the TCP Connection Attempt Time, Can exist on an interface

Configuring IP Services

Configuring TCP Performance Parameters

The CEF and fast-switching aspects of the Express TCP Header Compression feature are related to these documents:

•Cisco IOS Switching Services Configuration Guide

•Cisco IOS Switching Services Command Reference

For information about compressing RTP headers, see the chapter “Configuring IP Multicast Routing” in this document.

Changing the Number of TCP Header Compression Connections

You also can specify the total number of header compression connections that can exist on an interface. You should configure one connection for each TCP connection through the specified interface.

When specifying the total number of header compression connections that can exist on an interface, be aware of the following conditions:

•By default, for Frame Relay encapsulation, there can be 256 TCP header compression connections (128 calls). The maximum value is fixed, not configurable.

•By default, for PPP or HDLC encapsulation, the software allows 32 TCP header compression connections (16 calls). This default can be increased to a maximum of 256 TCP header compression connections.

To specify the number of connections, use the following command in interface configuration mode:

Command	Purpose
Router(config-if)# ip tcp	Specifies the total number of TCP header compression connections that
compression-connections number	can exist on an interface.

Setting the TCP Connection Attempt Time

You can set the amount of time the Cisco IOS software will wait to attempt to establish a TCP connection. Because the connection attempt time is a host parameter, it does not pertain to traffic going through the device, just to traffic originated at the device.

To set the TCP connection attempt time, use the following command in global configuration mode:

Command	Purpose
Router(config)# ip tcp synwait-time seconds	Sets the amount of time the Cisco IOS software will wait to attempt to
	establish a TCP connection.The default is 30 seconds.

Enabling TCP Path MTU Discovery

Path MTU Discovery is a method for maximizing the use of available bandwidth in the network between the endpoints of a TCP connection, and is described in RFC 1191. By default, this feature is disabled. Existing connections are not affected when this feature is turned on or off.

Cisco IOS IP Configuration Guide

IPC-112