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Frame Relay technology, theoretical question

Hello all,

I am working on a MPLS paper, interested in including some FR, ATM background info. Taking a closer look at Frame Relay encapsulation I found:

1. No frame structure information for Cisco proprietary FR encapsulation, which is very unfortunate since all of our networking equipment is Cisco made.

2. Got a question on IETF RFC 2427 encapsulation, which states that all protocols must encapsulate within Q.922 Annex A (aka DL-CORE) frame, but again uses control field according to Q.922 which is *not* Annex A.

So my questions go:

1. Is it possible to find the frame structure of Cisco FR encapsulation?

2. Does RFC 2427 (by using the above mentioned verbalization) means that: yes it does use control field according to Q.922 description but it actually places the control field inside the Data part of the Annex A frame making it transparent to the FR network (visible only end-to-end and not point-to-point)?

3. If the above (Q2) stands true is there any actual/real life DL-CONTROL implementation?

Thank you,