Cisco Cisco Packet Data Gateway (PDG) Fehlerbehebungsanleitung
L2TP Access Concentrator
▀ Supported LAC Service Configurations for PDSN Simple IP
▄ Cisco ASR 5000 Series Enhanced Feature Configuration Guide
OL-22982-01
Attribute-based Tunneling
This section describes the working of attribute-based tunneling and its configuration.
How The Attribute-based L2TP Configuration Works
The following figure and the text that follows describe how Attribute-based tunneling is performed using the system.
Figure 27. Attribute-based L2TP Session Processing for SIP
1. A subscriber session from the PCF is received by the PDSN service over the R-P interface.
2. The PDSN service attempts to authenticate the subscriber. The subscriber could be configured either locally or
2. The PDSN service attempts to authenticate the subscriber. The subscriber could be configured either locally or
remotely on a RADIUS server. Figure above shows subscriber authentication using a RADIUS AAA server.
3. The RADIUS server returns an Access-Accept message, which includes attributes indicating that session data is
to be tunneled using L2TP, and the name and location of the LAC service to use. An attribute could also be
provided indicating the LNS peer to connect to.
provided indicating the LNS peer to connect to.
4. The PDSN service receives the information and then forwards the packets to the LAC service, configured within
the Destination context.
5. The LAC service, upon receiving the packets, encapsulates the information and forwards it to the appropriate
PDN interface for delivery to the LNS.