Cisco’s CCNA certification (Cisco Certified Network Associate) is an introductory-level certification. The 640-801 single exam option is the most popular route to earning the CCNA, however, a two-exam option was introduced by Cisco in 2003. The CCNA is designed for IT professionals who can “install, configure, and operate LAN, WAN, and dial access services for small networks (100 nodes or fewer), including but not limited to use of these protocols: IP, IGRP, Serial, Frame Relay, IP RIP, VLANs, RIP, Ethernet, Access Lists.”

The CCNA can be used as a starting point for higher level certifications, such as the CCNP (Cisco Certified Network Professional) and CCDP (Cisco Certified Design Professional). It is a prerequisite for each of these certifications.

The CCNA got its start back several years ago. It was most recently changed in the summer of 2003 when a two exam path (INTRO and ICND) was added as an alternative to the one exam path (CCNA). The CCNA is valid for three years. “To recertify, pass the current exam or any new exam at the Professional or Cisco Qualified Specialist level bearing the prefix 642.”

Job roles of those pursuing this certification generally include: systems administrator and network administrator.

For more information:
http://www.cisco.com/en/US/learning/le3/le2/le0/le9/learning_certification_type_home.html

CORE EXAMS
Retired: (640-607) 640-607 CCNA ^vs 
(640-801) 640-801 CCNA ^vs 
(640-811) 640-811 ICND ^vs 
(640-821) 640-821 INTRO ^vs