Finite state automata congestion control

Virtual template 1 was applied to virtual access interface 3. Virtual-Access3 VPN Clone from Vtemplate 1 block=1 filterPPP=0 Virtual access interface 3 was set to asynchronous for character-by-character transmission. Virtual-Access3 VPN Virtual interface created for access interface was set up on the tunnel server for the user VPN Set to Async interface

PPP CHAP authentication status for the tunnel named nas1. L2F: Chap authentication succeeded for nas1. The network access server (NAS) has the following VPDN configuration: Debugging Control Channel Authentication EventsДebugging VPDN Events on a NAS-Normal L2F Operations.Debugging an L2TPv3 Xconnect Session-Normal Operations.Debugging L2F Control Packets for Complete Information.Debugging Errors on the NAS-L2F Error Conditions.Displaying L2TP Congestion Avoidance Settings.Debugging Protocol-Specific Events on the Tunnel Server-Normal L2F Operations.Debugging Protocol-Specific Events on the NAS-Normal L2F Operations.Debugging VPDN Events on the Tunnel Server-Normal L2TP Operations.Debugging VPDN Events on the NAS-Normal L2TP Operations.Debugging VPDN Events on the Tunnel Server-Normal L2F Operations.Debugging VPDN Events on a NAS-Normal L2F Operations.This section contains the following examples: Depending on the L2TP traffic pattern, these commands may cause the CPU load to increase to a high level that impacts performance. Note that the debug vpdn packet and debug vpdn packet detail commands generate several debug operations per packet. To disable debugging output, use the no form of this command.Дebug vpdn keywords. To troubleshoot Layer 2 Forwarding (L2F) or Layer 2 Tunnel Protocol (L2TP) virtual private dialup network (VPDN) tunneling events and infrastructure, use the debug vpdn command in privileged EXEC mode. This section documents new and modified commands. L2TP congestion avoidance is also useful on highly scalable platforms such as the Cisco 10000 router, which supports a large number of simultaneous sessions.Д¬onfiguration information is included in the 'VPDN Tunnel Management' chapter in the Cisco IOS VPDN Configuration Guide, ReleaseВ 12.4T, at the following URL: L2TP congestion avoidance is useful in networks with a relatively high rate of calls being placed by either tunnel endpoint. The window size grows larger when packets are delivered successfully, and is reduced when dropped packets must be retransmitted. Configuring the L2TP Congestion Avoidance feature allows the L2TP packet window to be dynamically resized using a sliding window mechanism.

Throttling L2TP control message packets prevents dropped sessions when the peer's input buffer overflows.Д«efore the introduction of the L2TP Congestion Avoidance feature, the window size used to send packets between the network access server (NAS) and the tunnel server was set to the value advertised by the peer endpoint and was never changed. The L2TP Congestion Avoidance feature provides packet flow control and congestion avoidance by throttling Layer 2 Transport Protocol (L2TP) control messages as described in RFC 2661.

L2TP Congestion Avoidance Table Of Contents

Finite state automata congestion control