The CCNA certification validates the ability to install, configure, operate, and troubleshoot medium-size routed and switched networks. CCNA certified professionals have the knowledge and skills to make connections to remote sites via a WAN, mitigate basic security threats, and understand the requirements for wireless network access. CCNA training covers (but is not limited to) the use of these protocols: IP, Enhanced Interior Gateway Routing Protocol (EIGRP), Serial Line Interface Protocol Frame Relay, Routing Information Protocol Version 2 (RIPv2), VLANs, Ethernet, and access control lists (ACLs).

Source: https://learningnetwork.cisco.com/community/certifications/ccna/syllabus