I'm trying to wrap my head around QoS and I guess I have to start at the beginning - classification. I have a TDM to IP device that sets a ToS value of 0x08 to packets before it forwards the frame out towards the LAN.
Now as I understand it, ToS is an IP tag so I'm having a hard time understanding whether or not a L2 switch can read the ToS bit, map it to CoS to send about the LAN to the router, at which point CoS is mapped to DSCP, shipped out the WAN to the far end router where DSCP is mapped back to CoS to it's destination port.
I understand that the next steps are Policing, Marking and Queuing, and I'll cross those bridges when I come to them, but at this point, I think I just need to understand how the classification works on an L2 switch. The switch in question is a 2970 running 12.2(25)SEB4.
Thanks in advance.