Which protocol is used for AToM pseudowire control-plane signaling?

LDP.

What are the three steps of AToM pseudowire setup between peer PE routers (assuming an LDP session has not yet been established between PE routers)?

LDP discovery, LDP session initialization (establishment), and LDP Label Mapping exchange (VC/PW label bindings exchange).

An AToM data-plane packet typically consists of which elements?

One or more tunnel labels, a PW/VC label, an optional control word, and a payload.

Can TDP be used to signal the tunnel LSP? Can TDP be used to signal AToM PW/VClabels?

Yes, it can be used to signal the tunnel LSP. No, it cannot be used to signal PW/VC labels; these must be signaled using LDP.

If an AToM HDLC pseudowire is used to transport Frame Relay (Frame Relay portmode), in what way do PE routers participate in LMI?

They do not participate at all in LMI.

How can Layer 2 traffic to be forwarded between attachment circuits on the same PE router?

Using local switching.

What is one method of configuring RVSP-TE signaled tunnel LSPs to transport AToM pseudowires between PE routers?

Tunnel selection.

When transporting ATM cells over an AToM cell relay pseudowire, how is it possible to transport more than one ATM cell per AToM data-plane packet?

By using ATM cell relay with cell packing.

How is it possible to connect dissimilar attachment circuit types over AToM pseudowires?

Using L2VPN interworking.

What are the two modes of L2VPN interworking?

Ethernet mode and IP mode.