Software
Wireshark
PuTTY
TeraTerm
SecureCRT
HyperTerminal Private Edition
Kiwi Syslog Server
NMap
TFTPd64
Java
Free Radius
Ubuntu
GNS3
Cisco Packet Tracer
Cisco Configuration Professional (Requires free CCO account)
Cisco Configuration Assistant (Requires free CCO account)
Cisco Network Assistant (Requires free CCO account)