Multicast Features; Ipv4 Multicast Features - Dell PowerConnect 8024 User Manual

Priority-based Flow Control (PFC)
The Priority-based Flow Control feature allows the user to pause or inhibit transmission of individual
priorities within a single physical link. By configuring PFC to pause a congested priority (priorities)
independently, protocols that are highly loss sensitive can share the same link with traffic that has
different loss tolerances. Priorities are differentiated by the priority field of the 802.1Q VLAN header.
NOTE: An interface that is configured for PFC is automatically disabled for 802.3x flow control.
For information about PFC, see "Priority-based Flow Control (PFC)."

Multicast Features

IPv4 Multicast Features

Updated IPv4 Multicast Routing Support
The Multicast package code has been extensively re-engineered and furnished with the following:
• PIM-DM advanced to RFC 3973
• PIM-SM advanced to RFC 4601, pim-sm-bsr-05, draft-ietf-pim-mib-v2-03
• DVMRP advanced to draft-ietf-idmr-dvmrp-v3-10.txt, draft-ietf-idmr-dvmrp-mib-11.txt
Distance Vector Multicast Routing Protocol
Distance Vector Multicast Routing Protocol (DVMRP) exchanges probe packets with all DVMRP-
enabled routers, establishing two way neighboring relationships and building a neighbor table. It
exchanges report packets and creates a unicast topology table, which is used to build the multicast
routing table. This multicast route table is then used to route the multicast packets.
Internet Group Management Protocol
The Internet Group Management Protocol (IGMP) is used by IPv4 systems (hosts and routers) to report
their IP multicast group memberships to any neighboring multicast routers. The PowerConnect
8024/8024F performs the "multicast router part" of the IGMP protocol, which means it collects the
membership information needed by the active multicast routing.
Protocol Independent Multicast-Dense Mode
Protocol Independent Multicast (PIM) is a standard multicast routing protocol that provides scalable
inter-domain multicast routing across the Internet, independent of the mechanisms provided by any
particular unicast routing protocol. The Protocol Independent Multicast-Dense Mode (PIM-DM)
protocol uses an existing Unicast routing table and a Join/Prune/Graft mechanism to build a tree. PIM-
DM creates source-based shortest-path distribution trees, making use of reverse path forwarding (RPF).
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Introduction