OSPF типы LSA
LSA Types
1 Router LSA - generate by router per each area. Router ID. Stay within the area.
2 Network LSA - network state. Generate by DR within the area.
3 Summary LSA (ABR) - Generate by ABR.
4 ASBR summary - Generate by ASBR
5 External LSA - Information about external network
6 Multicast LSA - did not use
7 NSSA external LSA - NSSA forbidden to use LSA 5. Generate LSA 7 for external network.
All LSA packets except Hello carry LSA information.
DBD
1 Router LSA describe interface or link on the router. Or Virtual Link.
Flags:
V if =1 endpoint for Virtual Link
E if =1 generated by ASBR
B if =1 generated by ABR
Link type
1 - p2p network
2 - Transit network (NBMA, broadcast)
3 - Stub network
4 - Virtual link
Metric - cost of link
2 Network LSA
Link State ID - DR
Attached router - list of ID router with install AJ with DR(include DR)
3&4 Network and ASBR Summary
Link State ID - ip of advertising network
Link State ID - ip address of ASBR
5 External-LSA
Link State ID - ip of advertising network
E - external type. 0 - Type 1. 1 Type 2.
Forwarding address - to with IP forward packets. If 0.0.0.0 - forward to ASBR.
External Route Tag - Tag from external route
7 NSSA external LSA
Link State ID - ip of advertising network