Comprehensive and Detailed In-Depth Explanation:
Understanding the LSA Table in the Figure
The LSDB (Link-State Database) of R4 displays an Intra-Area-Prefix-LSA for Area 0.0.0.1. The table contains:
* Three LSAs originating from R4 (10.0.4.4)
* Prefixes referencing both Router-LSAs and Network-LSAs
* Different Sequence Numbers and Checksums, indicating multiple link-state changes OSPFv3 LSA Types Relevant to the Question
* Router-LSA (Type 1)
* Generated by every router to describe its links within an area.
* Network-LSA (Type 2)
* Generated only by the Designated Router (DR) for multi-access networks (such as Ethernet).
* Advertises all routers connected to the same segment.
* Intra-Area-Prefix-LSA (Type 9)
* Advertises IPv6 prefixes associated with a Router-LSA (Type 1) or Network-LSA (Type 2).
Analysis of Each Statement
A: The three LSAs belong to area 1. # (True)
* The table explicitly shows "Intra-Area-Prefix-LSA (Area 0.0.0.1)", meaning all LSAs are for Area 1.
* The Link State IDs also indicate intra-area advertisements.
# Statement A is correct.
B: Area 1 is a stub area. # (False)
* There is no indication that Area 1 is a stub area.
* Stub areas do not receive Type 5 (External) LSAs, and the LSDB does not show Type 3 (Inter- Area) LSAs either.
* Network-LSAs (Type 2) are not typically seen in stub areas unless explicitly configured.
# Statement B is incorrect.
C: No OSPFv3 neighbor relationship is established on at least one link of R4. # (True)
* One LSA references a Router-LSA, while two reference Network-LSAs.
* A Router-LSA alone suggests that R4 has at least one point-to-point or unnumbered link with no OSPFv3 adjacency.
* This means R4 has an interface with no neighbor (e.g., a passive interface or down link).
# Statement C is correct.
D: R4 is the DR on a link. # (True)
* The presence of Network-LSAs (Type 2) indicates that a multi-access link exists.
* Since R4 is the origin of the Network-LSA, it must be the DR (Designated Router) for that link.
# Statement D is correct.
Final Conclusion:
# A. The three LSAs belong to area 1. (True)# B. Area 1 is a stub area. (False)# C. No OSPFv3 neighbor relationship is established on at least one link of R4. (True)# D. R4 is the DR on a link. (True) Thus, the correct answers are: A, C, D.