CCDE: Cisco Certified Design Expert (Practical) — Question 133

Two routers R1 and R2 are directly connected through an Ethernet link. Both routers are running OSPF over the Ethernet link and OSPF has been registered with BFD. R1 has been set up to transmit BFD at a 50 ms interval, but R2 can receive only at a 100 ms rate due to platform limitations. What does this mean?

Answer options

• A. After the initial timer exchange, R2 sets its transmission rate to the R1 Desired Min TX interval
• B. After the initial timer exchange, R1 sets its transmission rate to the R2 Required Min RX interval
• C. Timers renegotiate indefinitely, so the timer exchange phase never converges
• D. R2 sets the P-bit on all BFD control packets until R2 sends a packet with the F-bit set

Correct answer: B

Explanation

The correct answer is B because R1 must adhere to the slower receiving capability of R2 and thus adjust its transmission rate to match R2's Required Min RX interval. Options A and C are incorrect as they misinterpret the behavior of the timer exchange, and option D is irrelevant to the context of BFD transmission rates.