Which Layer in the Cisco Enterprise Architecture model is highly available, has fast convergence, and should avoid packet manipulation?
A. Campus distribution
B. enterprise data center
C. enterprise edge
D. campus access
E. campus core
F. remote access VPN
Answert E is correct.
The core is a high-speed, Layer 3 switching environment using hardware-accelerated services. For fast convergence around a link or node failure, the core uses redundant point-to-point Layer 3 interconnections because this design yields the fastest and most deterministic convergence results. The core layer is designed to avoid any packet manipulation, such as checking access lists and filtering, which would slow down the switching of packets.
Source: http://www.ciscopress.com/articles/article.asp?p=1315434