Enterasys ssr-glx19-02 Guía Del Usuario

Task Force (IETF) document. The SSR’s implementation of DVMRP supports the 
following:

•

mtrace, which is a utility that tracks the multicast path from a source to a receiver.

•

Generation identifiers, which are assigned to DVMRP whenever that protocol is 
started on a router.

•

Pruning, which is an operation DVMRP routers perform to exclude interfaces not in 
the shortest path tree.

DVMRP uses the Reverse Path Multicasting (RPM) algorithm to perform pruning. In 
RPM, a source network rather than a host is paired with a multicast group. RPM permits 
the SSR to maintain multiple multicast groups.

On the SSR, DVMRP can be configured on a per interface basis. An interface does not have 
to run both DVMRP and IGMP. You can start and stop DVMRP independently from other 
routing protocols. IGMP starts and stops automatically with DVMRP.

To support backward compatibility on DVMRP interfaces, you can configure the router 
expire time and prune time on each SSR DVMRP interface. This lets it work with older 
versions of DVMRP.

You can use threshold values and scopes to control internetwork traffic on each DVMRP 
interface. Threshold values determine whether traffic is either restricted or not restricted 
to a subnet, site, or region. Scopes define a set of multicast addresses of devices to which 
the SSR can send DVMRP data. Scopes can include only addresses of devices on a 
company’s internal network and cannot include addresses that require the SSR to send 
DVMRP data on the internet.

You can also configure tunnels on SSR DVMRP interfaces. A tunnel is used to send 
packets between routers separated by gateways that do not support multicast routing. A 
tunnel acts as a virtual network between two routers running DVMRP. A tunnel does not 
run IGMP.

You can configure DVMRP routing on the SSR by performing the following DVMRP-
configuration tasks. You can create IP interfaces as discussed in 

. The following DVMRP-configuration tasks are discussed in this chapter:

•

Setting global parameters that will be used for all the interfaces on which DVMRP is 
enabled.

•

Configuring DVMRP on individual interfaces. You do so by enabling and disabling 
DVMRP on interfaces and then setting DVMRP parameters on the interfaces on which 
DVMRP is disabled.

•

Defining DVMRP tunnels, which IP uses to send multicast traffic between two end 
points.