Verilink 9000 Series (34-00271) Product Manual - Manual (Page 312)

290 C HAPTER 18: IP R OUTER
Link State
Advertisement
(LSA)
(OSPF only)
Describes the local state of a router or network. This includes the state of the
route’s interfaces and adjacencies. Each link state advertisement is flooded
throughout the routing domain. The collected link state advertisements of all
routers and networks forms the protocol's topological database.
Lower-level
Protocols
(OSPF only)
The underlying network access protocols that provide services to the Internet
Protocol. Examples of these are the X.25 packet and frame levels for X.25 PDNs,
and the ethernet data link layer for ethernets.
Multi-access
Networks
Those physical networks that support the attachment of multiple (more than two)
routers. Each pair of routers on such a network is assumed to be able to
communicate directly (e.g., multi-drop networks are excluded).
Neighboring
Routers
Two routers that have interfaces to a common network. On multi-access networks,
neighbors are dynamically discovered by OSPF's Hello Protocol.
Network In this document, an IP network, subnet, or supernet. It is possible for one physical
network to be assigned multiple IP network and subnet numbers. These are
considered to be separate networks. Point-to-point physical networks are an
exception—they are considered a single network no matter how many (if any at
all) IP network and subnet numbers are assigned to them.
Network Mask A 32-bit number indicating the range of IP addresses residing on a single IP
network/subnet/supernet. This document displays network masks as decimal
numbers. For example, the network mask for a Class C IP network is displayed as
255.255.255.0.
Router A level-three Internet Protocol packet switch. Formerly called a gateway in much
of the IP literature.
Router ID
(OSPF only)
A 32-bit number assigned to each router running the OSPF protocol. This number
uniquely identifies the router within an autonomous system.