3Com Router Command Reference Guide — V1.00ParameterNoneDescriptionUsing the tunnel avp-hidden command, you can enable hiding AV (attribute value)pairs. Using the undo tunnel avp-hidden command, you can disable hiding AV pairs.By default, hiding AV pairs is disabled.This command can be used on both LAC and LNS, and is an optional configuration.Upon configuration, the operation of hiding AV pairs makes sense only after tunnelauthentication and tunnel password are configured. When AV pairs are hidden, L2TPhidden algorithm will be executed so that the username and password transmitted inplain text during proxy authentication will be encrypted into AV pairs. Hiding AV pairsin L2TP application is very useful when PAP or proxy authentication is used betweenLAC and LNS.In actual configuration, it is recommended to enable/disable hiding AV pairs on bothLAC and LNS at the same time.Example# Enable hiding AV pairs on L2TP group 1.[3Com-l2tp1] tunnel avp-hidden1.1.16 tunnel flow-controlSyntaxtunnel flow-control receive-window sizeundo tunnel flow-control receive-windowViewL2TP group viewParameterreceive-window size: Specify the size of the receiving window of tunnel. It is aninteger in the range from 0 to 100. By default, the size of the receiving window oftunnel flow control is 0, which means there is no flow control.16
