CCIE Service Provider (legacy) — Question 1

A service provider engineering team must design a solution that supports end-to-end LSPs for multiple IGP domains within different AS numbers.
According to RFC 3107, which solution achieves this goal?

Answer options

• A. LDP and BGP
• B. BGP and send-label
• C. RSVP and IS-IS or OSPF
• D. RSVP and BGP
• E. mLDP

Correct answer: B

Explanation

The correct answer is B, as BGP with the send-label capability allows for the distribution of labels across different AS numbers, which is essential for achieving end-to-end LSPs. Options A and D involve LDP and RSVP respectively, which do not support inter-domain label distribution as effectively as BGP. Options C and E are also not aligned with the requirements specified in RFC 3107 regarding the use of BGP for multi-domain scenarios.