The TCP time out settings in the Vigor2820 are configured using the command line command “portmaptime” as shown below:
The default TCP timeout is 86400 seconds.
To change this setting use the command “portmaptime -t ”

PortmapTimeSetting [- | … ]
-t :     set TCP protocol session timeout.
-u :    set UDP protocol session timeout.
-i :     set IGMP protocol session timeout.
-w :    set TCP WWW protocol session timeout.
-s :     set TCP SYN protocol session timeout.
-f :     flush all portmaps (useful for diagnostics)
-l :     List your all setting

Default Settings
2820> portmaptime -l
—— Current setting ——
TCP Timeout : 86400 sec.
UDP Timeout : 180 sec.
IGMP Timeout : 10 sec.
TCP WWW Timeout: 60 sec.
TCP SYN Timeout: 60 sec.

Example to set TCP protocol session timeout to 100000 seconds,

first telnet to the router and use the command:

portmaptime –  t 100000