Cisco IOS in a Nutshell, 2nd Edition

Name

ip tcp window-size — global

Synopsis

ip tcp window-size bytes
no ip tcp window-size bytes

Configures

The window size of a TCP connection

Default

2,144 bytes

Description

This command sets the size of the TCP window to bytes. Changing the size of the TCP window modifies the size and number of packets that can fit within that window. With the default window of 2,144 bytes, you could buffer two 1,000-byte packets, or 21 100-byte packets. Regardless of the window’s size, the number of packets within the window is restricted to the values set by the ip tcp queuemax command; they default to 5 for TTY interfaces (async and console interfaces) and 20 for other interfaces. The maximum size of the window is 65,536 bytes.

Example

ip tcp window-size 4000