Question 2/XV - Characteristics of equipment for the digital
transmission of
television signals
(Continuation of Question 3/XV 1985-88)

Considering

(1) that CMTT is studying coding standards to be used in the
transmission of broadcast-type television signals over the digital
network;

(2) that it is becoming increasingly difficult to carry television
signals over standardized digital paths;

(3) that CMTT Recommendations 604 and 658 refer to Digital Television
Transmission and Mixed Analogue and Digital Transmission of Analogue
Composite Television Signals, respectively;

(4) that CMTT Report 646 describes the CMTT's studies on digital and
mixed analogue-and-ditital transmission of television signals,

1. What should be the characteristics of equipment for the digital
transmission of television signals over the digital network?

2. What should be the characteristics of transmission equipment for the
digital transmission of television signals over standardized digital
paths in a mixed analogue and digital network?

Points for study

1.Characteristics of video interfaces.

2. Characteristics of digital transmission interfaces.

3. Test methods.

4. Maintenance aspects.

5.Application of Operations, Administration and Maintenance interfaces
as given in Recommendation G.771 - any unique features required.

6.Characteristics of the equipment when signals are presented in a
variety of forms - including:

6.1 analogue composite signals
6.2 multiplexed analogue component signals
6.3 digital component signals
6.4 encrypted analogue signals
6.5 encrypted digital signals
6.6 high definition television (HDTV) signals

7.Characteristics when the equipment is used for:

7.1 contribution
7.2 primary distribution
7.3secondary distribution taking into account potential needs for
harmonization with non-distributive services, see Question 3/XV (Visual
telephone systems).

Notes

1. CMTT is responsible for recommending standards for the digital
encoding of television signals of broadcast type and testing methods for
television transmission, and account should be taken of their work in
this area.

2. Study Group IV is responsible for the maintenance of television
transmission links, and account should be taken of its work in this
area.

3. Account should be taken of the studies of broadband ISDN undertaken
by Study Group XVIII.

4. The study of this Question should be coordinated with the study of
Question 3/XV (Visual telephone systems).

5. Operations, Administration and Maintenance interfaces on transmission
equipment are studied under Question 9/XV.

6. Study Group XVIII are responsible for general network issues and
should be kept informed of any likely network implications arising from
the study of this Question including coding standards originating in
CMTT.