In which scenario is eBGP typically used?

In which scenario is eBGP typically used?

• A. Between routers within the same autonomous system.
• B. Between routers of different autonomous systems.
• C. Between a CE router and a PE router.
• D. Between PE routers in the same location.

Answer: (B)

eBGP, or External Border Gateway Protocol, is utilized primarily between routers that belong to different autonomous systems. This protocol is specifically designed for exchanging routing information across the internet or other large networks where multiple organizations or entities operate independently. The primary purpose of eBGP is to facilitate communication and routing between these diverse networks, making it essential for inter-domain routing. In contrast, scenarios involving routers within the same autonomous system utilize iBGP (Internal BGP). Also, options mentioning the connection between a Customer Edge (CE) router and a Provider Edge (PE) router or PE routers in the same location deal with internal network configurations rather than the inter-domain focus of eBGP. Therefore, the emphasis on different autonomous systems highlights why using eBGP in such contexts is crucial for maintaining robust and scalable routing across various network boundaries.

eBGP, or External Border Gateway Protocol, is utilized primarily between routers that belong to different autonomous systems. This protocol is specifically designed for exchanging routing information across the internet or other large networks where multiple organizations or entities operate independently. The primary purpose of eBGP is to facilitate communication and routing between these diverse networks, making it essential for inter-domain routing.

In contrast, scenarios involving routers within the same autonomous system utilize iBGP (Internal BGP). Also, options mentioning the connection between a Customer Edge (CE) router and a Provider Edge (PE) router or PE routers in the same location deal with internal network configurations rather than the inter-domain focus of eBGP. Therefore, the emphasis on different autonomous systems highlights why using eBGP in such contexts is crucial for maintaining robust and scalable routing across various network boundaries.