Riverstone Networks WICT1-12 - Manual (Page 469)

Riverstone Networks RS Switch Router User Guide Release 8.0 19-5
Multicast Routing Configuration Configuring DVMRP
To configure neighbor timeout or prune time, enter one of the following commands in Configure mode:
19.4.4 Configuring the DVMRP Routing Metric
You can configure the DVMRP routing metric associated with a set of destinations for DVMRP reports. The default
metric is 1.
To configure the DVMRP routing metric, enter the following command in Configure mode:
19.4.5 Configuring DVMRP TTL & Scope
For control over internet traffic, per-interface control is allowed through Scopes and TTL thresholds.
The TTL value controls whether packets are forwarded from an interface. The following are conventional guidelines
for assigning TTL values to a multicast application and their corresponding RS setting for DVMRP threshold:
TTL = 1 Threshold = 1 Application restricted to subnet
TTL < 16 Threshold = 16 Application restricted to a site
TTL < 64 Threshold = 64 Application restricted to a region
TTL < 128 Threshold = 128 Application restricted to a continent
TTL = 255 Application not restricted
To configure the TTL Threshold, enter the following command in Configure mode:
TTL thresholding is not always considered useful. There is another approach of a range of multicast addresses for
“administrative” scoping. In other words, such addresses would be usable within a certain administrative scope, a
corporate network, for instance, but would not be forwarded across the internet. The range from 239.0.0.0 through
239.255.255.255 is being reserved for administratively scoped applications. Any organization can currently assign this
range of addresses and the packets will not be sent out of the organization. In addition, multiple scopes can be defined
on per-interface basis.
Configure the DVMRP neighbor timeout.
dvmrp set interface
<ip-addr>
neighbor-timeout
<number>
Configure the DVMRP prune time.
dvmrp set interface
<ip-addr>
prunetime
<number>
Configure the DVMRP routing metric.
dvmrp set interface
<ip-addr>
metric
<number>
Configure the TTL Threshold.
dvmrp set interface
<ip-addr>
threshold
<number>