Question 6/II - Evolution of routing plan in the ISDN era
(Combination and expansion of Questions 18/II and
19/II studied in the 1985-1988 period)

Considering

(a) the evolution of the world networks towards ISDN;

(b) the multiservice aspects of the ISDN (e.g., Packet Mode Bearer
Service) with the possibility that each service will require different
routing algorithms;

(c) that there may be new signalling elements and SPC capabilities that
will also require analysis for call routing (e.g., number of links with
DCME, number of echo control devices, number of A/MV law
conversions);

(d) the numbering interworking Recommendation and the need to
develop a clear Interworking Routing Plan for all services on the ISDN;

(e) that E.172 routing rules allow for the selection of signalling
systems
other than C7 ISUP for ISDN calls;

(f) the routing techniques outlined in Recommendation E.170, the
telephone routing plan (E.171) and the ISDN routing plan (E.172)
together with the experience gained from using these plans;

(g) the urgent need for guidance on call routing in support of mobile
networks,

What new Recommendations should be provided, or what revisions
and additions should be made to the existing Routing
Recommendations?

What further enhancements are required to the "connection history",
"performance monitoring/QoS" and "environment of connection"
parameters in order to enhance call routing capabilities?