Cisco connections

Cisco Networking Academy (official page, video – The Greatest Classroom in the World)

Cisco Career Certificates (wiki)

CCNA Exploration (official page, Data Sheet, FAQ, Demo of e-class)

CCNP (official page, Data Sheet, Demo of e-class)

CCNA Security (official page, Data Sheet, FAQ, Demo of e-class)

Simulation tool Packet Tracer (official page, video, Data Sheet)

The program for the analysis of traffic Wireshark

Web game Aspire (video)