Question 5/XV - Characteristics of direct transmission restoration
systems of
the 1+1 and N+M type (link protection switching)
(Continuation of Question 8/XV 1985-88)

Considering

(1) that Recommendations G.180 and G.181 give the characteristics of 1+1
and N+M type systems for the direct transmission restoration of digital
transmission equipment and links;

(2) that these Recommendations are incomplete and include a number of
provisional values;

(3) that direct transmission restoration systems using non- regenerative
equipment ensuring the switching of analogue as well as digital links
appear to be of interest,

1. How may Recommendations G.180 and G.181 be completed?

2. May the provisional values be definitively recommended or, if not,
how have they to be amended?

3. What characteristics should be recommended for direct transmission
restoration systems using non-regenerative equipment ensuring the
switching of analogue as well as digital links?

Notes

1. The equipment studied under point 3 of the Question may be object of
a separate Recommendation or included as special cases in
Recommendations G.180 and G.181.

2. The study of this Question should be coordinated with the study of
Questions 6/XV and 18/XV and 9/XV.