Quanta Cloud Technology QuantaMesh QNOS5, Руководство по настройке

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QNOS5, OSPF and BGP can use BFD for monitoring of their neighbors' availability in the network and for
fast detection of connection faults with them.
1.5.13. VRF Lite Operation and Configuration
The Virtual Routing and Forwarding feature enables a router to function as multiple routers. Each virtual
router manages its own routing domain, with its own IP routes, routing interfaces, and host entries. Each
virtual router makes its own routing decisions, independent of other virtual routers. More than one virtual
routing table may contain a route to a given destination. The network administrator can configure a subset of
the router's interfaces to be associated with each virtual router. The router routes packets according to the
virtual routing table associated with the packet's ingress interface. Each interface can be associated with at
most one virtual router.
1.6. Layer 3 Multicast Features
1.6.1. 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. PowerConnect 7000 Series
switches perform the “multicast router part” of the IGMP protocol, which means it collects the
membership information needed by the active multicast router.
1.6.2. Protocol Independent Multicast
1.6.2.1. Dense Mode ((PIM-DM)
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).
1.6.2.2. Spare Mode (PIM-SM)
Protocol Independent Multicast-Sparse Mode (PIM-SM) is used to efficiently route multicast traffic to
multicast groups that may span wide area networks, and where bandwidth is a constraint. PIM-SM uses
shared trees by default and implements source-based trees for efficiency. This data threshold rate is used
to toggle between trees.
1.6.2.3. Source Specific Multicast (PIM-SSM)
Protocol Independent Multicast—Source Specific Multicast (PIM-SSM) is a subset of PIM-SM and is used for
one-to-many multicast routing applications, such as audio or video broadcasts. PIM-SSM does not use
shared trees.