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Cisco Aironet 1400 Series Wireless Bridges Software Configuration Guide
OL-4059-01
Chapter 6 Configuring Radio Settings
Configuring the Fragmentation Threshold
Configuring the Fragmentation Threshold
The fragmentation threshold determines the size at which packets are fragmented (sent as several pieces
instead of as one block). Do not configure a fragmentation threshold that is lower than the concatenation
size, because the settings can conflict. If concatenation is disabled, use a low setting in areas where
communication is poor or where there is a great deal of radio interference.
The default setting is 4000 bytes. Beginning in privileged EXEC mode, follow these steps to configure
the fragmentation threshold:
Use the
no
form of the command to reset the setting to defaults.
Configuring Packet Concatenation
If your bridge often transmits bursts of data, such as voice packets, you can enable packet concatenation
to improve throughput. Concatenation is enabled by default to improve throughput.
Note
Not all devices connected through the bridge from the Ethernet LAN can support packet concatenation,
such as third party wireless clients connected to access points. Prior to configuring the packet
concatenation feature, ensure all your network devices support packet concatenation. Also ensure that
all bridges are running Cisco IOS Release 12.2(11)JA or later. If connectivity problems develop after
implementing packet concatenation, deactivate the concatenation feature to determine if that is the cause
of the problem.
Beginning in privileged EXEC mode, follow these steps to configure packet concatenation:
Command
Purpose
Step 1
configure terminal
Enter global configuration mode.
Step 2
interface dot11radio 0
Enter interface configuration mode for the radio interface.
Step 3
fragment-threshold
value
Set the fragmentation threshold. Enter a setting from 256 to
4000 bytes.
Step 4
end
Return to privileged EXEC mode.
Step 5
copy running-config startup-config
(Optional) Save your entries in the configuration file.
Command
Purpose
Step 1
configure terminal
Enter global configuration mode.
Step 2
interface dot11radio 0
Enter interface configuration mode for the radio interface.
Step 3
concatenation
[
size
bytes
]
Enable packet concatenation.
(Optional) Set a maximum size for concatenated packets in
bytes. Enter a value from 1600 to 4000. When concatenation is
enabled, the default packet size is 3500.
Step 4
end
Return to privileged EXEC mode.
Step 5
copy running-config startup-config
(Optional) Save your entries in the configuration file.