2)
Type:
The type of LSA. Table 10-5 enumerates several common features of LSA.
3)
Link State ID:
It has different meanings for different types of LSA. For details please refer
to the RFC documentation.
4)
Advertising Router:
ID of the router advertising this LSA.
5)
Sequence Number:
It indicates the uniqueness of a certain LSA, whose update would be
flooded to the network by adding 1 to the sequence number.
In the table below are the features of 6 types of common LSA.
Type
Code
Name
Features
1
Router LSA
Originates from all the routers, and describes the router
interface which itself has already run the OSPF features and
then spreads in its advertising area.
2
Network LSA Originates from DR, and describes the link state of all routers
in its connected network segment and then diffuses in its
advertising area.
3
Network
Summary
LSA
Originates from ABR, and describes the routers of all
segments in the area and then advertises to the backbone
area, the routers in which area will re-summarize and then
announce to the other area.
4
ASBR
Summary
LSA
Originates from ABR, and describes the routers from ABR to
ASBR and advertises the path to ASBR to the area ABR
connects.
5
AS External
LSA
Originates from ASBR, and describes the external route and
the accessible network obtained by other routing protocols.
This type of LSA will be flooded to the entire autonomous
system.
6
NSSA
External LSA
Originates from ASBR in the NSSA. The content of this LSA is
the same as that of AS external LSA, but it would be
advertised only to NSSA. ABR can transform this type of
routing information to AS external LSA and then flood it to the
entire AS.
Table 10-5 Types of LSA
OSPF Features Supported by the Switches
This switch, supporting standard OSPF routing features, is applicable to multiple network
environments and able to meet the common networking requirements in the Ethernet scene.
The OSPF features supported are listed as follows.
1)
Multi-process – The switch can establish multiple routing processes, independent of each
other and having independent database. Each routing interface belongs only to one
specific process. In short, multi-process on one switch is to divide one switch into several
independent switches logically.
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