Dynamips emulates a variety of Cisco routers on a traditional PC. It supports the emulation of select 7200, 3600, 3700, and 2600 series routers. It uses real Cisco IOS images (which are not part of this package). Of course, this emulator cannot replace a real router. It is simply a complementary tool to real labs for administrators of Cisco networks or people wanting to pass their CCNA/CCNP/CCIE exams.

WWW: https://github.com/GNS3/dynamips
