I have been working on a solution of carrying TDM over IP network (MPLS) - been labbing but it's eluding me. So far I am working with ASR 901's which give me a few options based on http://www.cisco.com/c/en/us/support/docs/wan/tdm/115921-ceop-satop-00.pdf document and the manual. I am getting a T1 fed from a metaswitch whch provides clocking.
Option 1 In−band PW/Adaptive Clocking is not supported on the ASR 901
Option 2 BITS clocking - kind of defeats the purpose if you are trying to transport TDM over distance to have a T1 between them to provide clocking. (unless perhaps you could stick something like http://www.symmetricom.com/products/time-frequency-references/telecom-primary-reference-sources/timesource-3000/#.UwajjIVOqXM at each "site" to provide clock - but does this not conflict with the clock the metaswitch is sending?)
Option 3 Synchronous Ethernet Clocking or Sync-E - requires every intermediary Ethernet device to support it/not feasible
Option 4 Out−of−band PW Clocking (virtual−cem) - not supported on ASR 901
Option 5 PTP Clocking (Timing over Packet) or IEEE 1588v2 - set this up but do not see a way to tell ROUTER1 to get clock from the metaswitch and then use that as the primary clock source to send to ROUTER2, then out that T1 to a 2811 VWIC-1MFT-T1
Maybe someone has some experience with this or can point me in the right direction. I've been working it for a while now and am fairly confused.