Samsung Ubigate iBG3026, Руководство по настройке

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CHAPTER 16. MultiCast Protocols
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DRIB
Ubigate iBG3026 DVMRP is a separate daemon serviced by the NSM daemon.
It maintains the DVMRP Routing Information Base(DRIB).
The DRIB contains the table of routes for multicast sources learned through
DVMRP route exchanges. Both the upstream and the downstream parts of a
route-state reside physically in a combined, single DRIB node. A DRIB node
is called a DVMRP Routing Table(DRT) entry.
The DRT entry contains a vector of downstream interfaces; each vector slot
position represents a virtual interface(VIF). It is used to store all required
information for the state to ultimately decide the set of forwarding interfaces
for corresponding multicasting data packets.
DVMRP requires a per-source network Designated Forwarder(DF) on each
downstream interface, i.e., DF(S, I). DF election is based on the metric toward
the source network.
If DF(S,I) changes for an interface, Ubigate iBG3026 updates the outgoing VIF
list(Olist) for all prune(S, G) states and their corresponding forwarding caches.
VIF Table
The VIF table is a tree of virtualized physical and tunnel interfaces indexed by
a virtual interface number.
Neighbor Table
The Neighbor table is a list of detected DVMRP neighbors on an interface.
Neighbors announce themselves using the Probe message.
Route Report Arrays of Lists
Because route reporting is done by grouping together all routes that belong to
the same mask, a Route Report Array of Lists(AOL) is used to expedite
general route reporting.
Configuration Example
The main requirement is to enable DVMRP on the desired interfaces.
This section provides a DVMRP configuration example for a relevant scenario.
In this example, the Source_1 address is 10.10.1.52, and the group address is
set to 224.0.1.3. The following figure displays the network topology used in
this example: 10.101.52