Switch Network Simulator provides a virtual lab environment by simulating a switch network consisting of Cisco IOS and Juniper JUNOS switches. Additionally, a lab manual provides hands-on experience configuration and troubleshooting of switch networks consisting of Cisco and Juniper switches.
Some screen shots of Switch Simulator
Switch Simulator main window
Cisco switch console simulator
Cisco GUI Switch Simulator
Juniper GUI Switch Simulator
Please checkout this for Cisco-juniper Switch simulator
Also check this for Available labs