CCDE: Cisco Certified Design Expert (Practical) — Question 128

Which extensions to GRE tunneling provide session tracking and in-order packet delivery in exchange for additional state stored in tunnel endpoints?

Answer options

• A. GRE Key and Sequence number extensions
• B. GRE Protocol Type and Checksum extension fields
• C. GRE Version and Reserved0 extension fields
• D. No extension fields are available in the GRE header to track session data and packet sequences

Correct answer: A

Explanation

The correct answer is A, as GRE Key and Sequence number extensions are specifically designed to manage session tracking and maintain the order of packet delivery by requiring additional state information. The other options either do not provide these capabilities or indicate that no extensions exist for this purpose.