Implementing Cisco Service Provider Advanced Routing Solutions (SPRI) — Question 141

An ISP has an MPLS VPN-based network with 12 PE routers. How many peerings are required between the 12 routers if the engineer has not configured route reflectors?

Answer options

• A. 60
• B. 66
• C. 78
• D. 84

Correct answer: B

Explanation

In a fully meshed network of n routers, the number of peerings required is calculated using the formula n(n-1)/2. For 12 routers, this results in 12(12-1)/2 = 66 peerings. The other options are incorrect as they do not follow this formula for the given number of routers.