3Com 3C421600A Reference Manual page 141

Accept Default — Disabled by default. Determines whether router
accepts default route advertisements.
Split Horizon — Enabled by default. Records the interface over which
it received a particular route and does not propagate its information
about that route back over the same interface. This prevents network
loops.
Poison Reverse — Disabled by default. Routes that were excluded due
to the use of split horizon are instead included with infinite cost (16).
The system continues to broadcast the route, but with an infinite cost.
Note: To perform poison reverse, you must also enable split horizon.
Flash Update — Enabled by default. It is also known as "triggered
update", meaning routes that have their metrics modified are
advertised immediately, instead of waiting for the next scheduled
broadcast.
The flags described are for backward compatibility with RIP version 1
when RIP version 2 is selected as the routing protocol.
Send Compatibility — Controls the selection of destination MAC and
IP addresses. It is enabled by default. When enabled, broadcast
address is used; when disabled, multicast address is used.
RIP V1 Receive — Controls the receipt of RIP version 1 updates. When
RIP version 1 is the selected routing protocol, this policy is enabled by
default, which means RIP version 1 packets are received. (When RIP
version 2 is chosen, this policy is enabled by default, meaning RIP
version 1 packets are received.
RIP V2 Receive — Controls receipt of RIP version 2 updates. When RIP
v1 is the selected routing protocol, this policy is enabled by default,
which allows RIPV1 packets to be received. When RIP version 2 is
selected, this policy is enabled by default, allowing RIPV2 packets to
be received. RIPV2 is backward compatible.
Silent — This flag tells RIPv2 not to send updates. It is disabled by
default.
Set Commands 141