Juniper M40E Hardware Manual page 81

Copyright © 2010, Juniper Networks, Inc.
Unicast routing protocols
BGP—Border Gateway Protocol, version 4, is an Exterior Gateway Protocol (EGP)
that guarantees loop-free exchange of routing information between routing domains
(also called autonomous systems). BGP, in conjunction with Junos routing policy,
provides a system of administrative checks and balances that can be used to
implement peering and transit agreements.
ICMP—Internet Control Message Protocol router discovery is a method that hosts
can use to discover the addresses of operational routers on a subnet.
IS-IS—Intermediate System-to-Intermediate System is a link-state interior gateway
protocol (IGP) for IP networks that uses the shortest-path-first algorithm (SPF
algorithm, also called the Dijkstra algorithm) to determine routes.
OSPF—Open Shortest Path First, version 2, is an IGP developed for IP networks by
the Internet Engineering Task Force (IETF). OSPF is a link-state protocol that makes
routing decisions based on the SPF algorithm.
RIP—Routing Information Protocol, version 2, is an IGP for IP networks based on the
Bellman-Ford algorithm. RIP is a distance-vector protocol. RIP dynamically routes
packets between a subscriber and a service provider without the subscriber having
to configure BGP or to participate in the service provider's IGP discovery process.
Multicast routing protocols
DVMRP—Distance Vector Multicast Routing Protocol is a dense-mode
(flood-and-prune) multicast routing protocol.
IGMP—Internet Group Management Protocol, versions 1 and 2, is used to manage
membership in multicast groups.
MSDP—Multicast Source Discovery Protocol enables multiple PIM sparse mode
domains to be joined. A rendezvous point (RP) in a PIM sparse mode domain has a
peering relationship with an RP in another domain, thereby discovering multicast
sources from other domains.
PIM sparse mode and dense mode—Protocol-Independent Multicast is a multicast
routing protocol used to route traffic to multicast groups that might span wide-area
and interdomain internetworks. In PIM sparse mode, routers explicitly join and leave
multicast groups. PIM dense mode is a flood-and-prune protocol.
SAP/SDP—Session Announcement Protocol and Session Description Protocol handle
conference session announcements.
MPLS application protocols
LDP—Label Distribution Protocol provides a mechanism for distributing labels in
nontraffic-engineered applications. LDP allows routers to establish label-switched
paths (LSPs) through a network by mapping network-layer routing information
directly to data-link layer switched paths. LSPs created by LDP can also traverse
LSPs created by Resource Reservation Protocol (RSVP).
Chapter 3: Junos OS Overview
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