This certification validates the ability to install, configure, operate, and troubleshoot medium-size routed and switched networks, including implementation and verification of connections to remote sites in a WAN.
CCNA certification requires exam passes in either:
- 640-802 CCNA, or
- both 640-822 ICND1 and 640-816 ICND2.
There are no prerequisites, but CCNA certifications are only valid for three years. Recertification can be achieved by either passing the current CCNA exam or the ICND2 exam or any 642 professional level or Cisco Specialist exam.
more information is available from the Cisco website