Qtech QSW-3900-48-SFP-DC [108/245] Network lsa

QTECH Software Configuration Manual

8-107

to a transit network; a value of 3 indicates a link to a stub network; a value of 4 indicates a virtual link.

· #TOS : Number of different TOS metrics given for this link.

· metric : Cost of using this router link.

· TOS : IP Type of Service that this metric refers to.

· TOS metric : TOS-specific metric information.

2) Network LSA

A Network LSA is originated by the DR on a broadcast or NBMA network. The LSA describes all routers

attached to the network.

Network LSA format

Major fields :

· Link State ID : The interface address of the DR

· Network Mask : The mask of the network (a broadcast or NBMA network)

· Attached Router : The IDs of the routers, which are adjacent to the DR, including the DR itself

3) Summary LSA

Network summary LSAs (Type-3 LSAs) and ASBR summary LSAs (Type-4 LSAs) are originated by ABRs. Other

than the difference in the Link State ID field, the format of type 3 and 4 summary-LSAs is identical.

Summary LSA format

Major fields :

· Link State ID : For a Type-3 LSA, it is an IP address outside the area; for a type 4 LSA, it is the router ID

of an ASBR outside the area.