Cisco Packet Tracer 6.1 (version 6.1.0.0120) has been available on netacad since July 2014 for Cisco Networking Academy members. A newer verion, Packet Tracer 6.1.1 has been released at the end of august. This is a minor release correcting bugs found in the previous 6.1.0.0120 version.
官网说明:https://www.packettracernetwork.com/features/packettracer-61-newfeatures.html
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