Samsung Ubigate iBG2016, Руководство по настройке

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CHAPTER 7. MultiCast Protocols
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© SAMSUNG Electronics Co., Ltd.
Distance Vector Multicast Routing Protocol
(DVMRP)
Distance Vector Multicast Routing Protocol(DVMRP) is a multicast routing
protocol that provides an efficient mechanism for connectionless datagram
delivery to a group of hosts across an internetwork. It is a distributed protocol
that dynamically generates IP multicast delivery trees using a technique called
Reverse Path Multicasting.
Terminology
Following is a brief description of terms and concepts used to describe the
DVMRP protocol.
DRIB
Ubigate iBG2016 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 iBG2016 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.