Tom,
On a related matter to the one you were discussing with Roberto, I've searched around and haven't been able to find what I'm looking for re: the interfacing of xDSL lines to ISDN.
Do you know of, or perhaps have any opinions on, a future NNI that will allow the interfacing of xDSL to ISDN in DSLAMs, or elsewhere? Perhaps NNI is not the proper term to use in this context, but what I am referring to is the ability of the xDSL loop to be used for universal transport, including ISDN.
Some forms of transmission are patently not conducive to IP networking, as you have pointed out, at this time and require a more robust and deterministic approach, such as that which ISDN supports, both for scaleability through bonding and guarantees on latency.
Similar capabilities to that which I am suggesting have already been established and published for xDSL to SONET, FR and ATM (for example, the SourceCom Banc 6000). How about ISDN?
My view is that if sufficient b/w or throughput exists for this purpose, and it is a HDSL modem that we're talking about, then it would be quite feasible, the main issue being that of the D channel handling. ADSL and VDSL, on the other hand, as it would appear to me, would require more finesse due to the asymmetry and shortage of bandwidth in many mfgrs units in the upstream direction. What do you think? Or is this old stuff, and I simply haven't been looking in the right places?
TIA, and Regards,
Frank Coluccio |
