Showing posts with label SAP. Show all posts
Showing posts with label SAP. Show all posts

Wednesday, September 3, 2014

Play with MACSEC on copper interface with 3750X

The Cisco documentation is not clear on the switch-to-switch (via copper) macsec feasibility.
Also, I have decided to test it between two 3750x:

  • 3750X-24TS (without service module)
  • 3750X-48TS (without service module)


I have applied the following configuration on each switch:


I have plugged the cable between this 2 switchs and checked that SAP 'succeeded':

Interface is up and configuration looks fine. But I have prefer checked by myself that the traffic is well encrypted. The best way to do this is to use a hub. But this equipment has disappeared from IT services and is very rare!! Also we have designed our own RJ45 TAP:).

I have used this magic TAP and wireshark to sniff the traffic between our both switchs.
Below, you can see the result of a packet when it's encrypted by MACSEC (802.1ae). We can see the Ethertype (88e5) used by this protocol.

To resume, MACSEC is available on Cisco Switch (switch-to-switch) on copper interface without Service Module. This configuration is not available on 3560X. I guess, the service module is mandatory for it.