RFC-1619 is a Proposed Standard, and may change based on the
implementation experience of the vendors as it goes to Draft Standard.
The only problem discovered so far is that some PTT equipment vendors
did not implement the SONET Loss of State (LOS) test requirement of 2.3
micro-seconds (119 unchanging zero/one bits at OC3), and instead
implemented 73-bits, the minimum from G.958 for a badly designed timing
recovery circuit. Many vendors are currently 'going around' Bellcore
by applying proprietary solutions to problems and convincing the RBOCs
that it doesn't matter if they are in long term partnerships.
ISO -- pick a standard, any standard.
This, in turn, may require an extra scrambling to be required. Not a
big hardware commitment, though, but a serious annoyance.
Interesting. If this happens, I can see lots of fun when trying to do
intercarrier interconnects. Of course, they will first have to reconcile
these issues with their current SONET infrastructures.
(Standard Disclaimer: the opinions expressed are strictly my own and are not
those of Bellcore)