Cisco Certified Network Associate (CCNA) Practice Exam

Which device typically generates Type 5 LSAs?

1. Internal routers

2. ABRs

3. ASBRs

4. DR routers

The correct answer is: ASBRs

Type 5 LSAs, also known as External LSAs, are primarily generated by Autonomous System Boundary Routers (ASBRs) in OSPF (Open Shortest Path First) networks. ASBRs are responsible for redistributing routes from other routing protocols into OSPF, which allows OSPF to incorporate external routing information. This is crucial in multi-protocol environments where OSPF needs to provide reachability to destinations outside its autonomous system. The function of ASBRs in generating Type 5 LSAs is essential for ensuring that OSPF can exchange information with and provide optimal routing to external networks, such as those running different protocols or connected to the internet. By doing so, ASBRs enable seamless communication and the integration of diverse networks. Other devices, such as internal routers, Area Border Routers (ABRs), and Designated Routers (DR), are responsible for different roles within OSPF, such as handling internal OSPF routing and managing the distribution of routing information within and between OSPF areas, but they do not generate Type 5 LSAs. This distinction emphasizes the specific role of ASBRs in OSPF and the importance of their function in the overall OSPF routing