3com 3031 Instruccion De Instalación

The two ends of the tunnel can be enabled or disabled checksum according to real 
application need. If the local end is enabled checksum, with the peer end disabled 
checksum, the local end will not perform checksum on the received packet, but 
perform checksum on the transmitted packet. On the contrary, the local end will 
perform checksum to the packet sent from the peer end, but will not perform 
checksum on the transmitted packet.

Perform the following configuration in tunnel interface view..

By default, end to end verification on both ends of Tunnel is disabled.

It is stipulated in RFC1701 that, if the KEY field in GRE header is set, the forwarder 
and the receiver will perform the verification on tunnel identification keyword. 
Only when the identification keyword set on both ends of the Tunnel are totally 
the same can the verification succeeds. Otherwise, the packet will be discarded.

Perform the following configuration in tunnel interface view.

In the table, the 

 is an integer ranging from 0 to 4294967295.

By default, Tunnel does not use KEY.

Route must exist on both the source end router and the destination end router, 
and must be forwarded via Tunnel, so that GRE packets can be forwarded 
properly. Either static routing or dynamic routing can be configured.

A route to destination address (not destination address of the Tunnel, but 
destination address of the packet before GRE encapsulation) can be configured 
manually, with next hop being the address of the peer end Tunnel interface. This 
configuration must be performed on both ends of the Tunnel. For details about 
this configuration, refer to Chapter 38 “Static Route Configuration”. For detailed 
descriptions on the configuration commands, refer to command manual related to 
this manual.

If dynamic routing protocol is performed on the router, simply enable this protocol 
on both Tunnel interface and the router interface directly connected with the 
private network. This configuration is required to be configured on both ends of 
the Tunnel. For details about this configuration, refer to “Configuring dynamic 
routing” in this chapter. For detailed descriptions on the configuration commands, 
refer to command manual related to this manual.

Table 978   Configuring the end to end verification on both ends of Tunnel

Set the end to end verification on both ends of Tunnel

Disable end to end verification on both ends of Tunnel

Table 979   Set the identification key word of tunnel interface

Set the identification key word of tunnel interface.

Cancel the identification key word of tunnel interface.