Extended Dvpn Function - 3Com 3C13636 Configuration Manual

3Com Router 3000 Ethernet Family
Configuration Guide
a DVPN domain and the configuration of the entire network, dramatically
improving network maintainability and automation degree.

4.1.6 Extended DVPN Function

Along with RADIUS server, DVPN server can implement accounting of DVPN users.
When completing authentication/authorization of a DVPN client, the DVPN server
records the user information of the DVPN client. After a session is established between
the DVPN client and the DVPN server, the DVPN server encapsulates information such
as the user name and the login time into the accounting start request, and sends the
request to the configured RADIUS server. Upon receiving the accounting start request,
the RADIUS server starts accounting and sends an accounting start response to the
DVPN server.
When the DVPN client logs out, the DVPN server sends an accounting stop request to
the RADIUS server. Upon receiving the accounting stop request, the RADIUS server
stops accounting and responds with an accounting stop acknowledgement.
After the RADIUS server starts accounting, accounting stop requests may fail to reach
the RADIUS server due to line or device failure, resulting in incomplete user accounting
information. To solve this problem, the DVPN server sends real time accounting
packets to the RADIUS server at a specified interval after the RADIUS server starts
accounting. The RADIUS server records the DVPN client information in the real time
accounting packets and responds to the DVPN server accounting acknowledgements.
If the DVPN server receives no response to the real time accounting packet, it
retransmits the packet at an interval. When the DVPN server has transmitted the
packet for the specified maximum attempts, if accounting optional is enabled on the
DVPN server, the DVPN server does not send the real time accounting packet any
more but maintains the DVPN connection. If accounting optional is not enabled on the
DVPN server, the DVPN server will tear down the DVPN connection.
Note:
You can configure the interval for sending real time accounting packets on the
RADIUS server using the timer realtime-accounting command. By default, the
interval is 12 minutes. For detailed configuration information, refer to the "Security"
part of the manual.
If the DVPN server receives no response to the real time accounting packet from the
RADIUS server, it retransmits the packet for the maximum times specified by using
the retry realtime-accounting command. The default maximum number for
sending the real time accounting packet is 5. For details, refer to the "Security" part
of the manual.
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Chapter 4 DVPN