1. ITU의 G 계열 권고 표준
ㅇ 디지털 전송망에 관한 것들에 대하여 권고하고 있음
- (Transmission Systems and Media, Digital Systems and Networks)
. 例) PDH, SDH, 다중화계위구조, 망동기방식 등
2. ITU-T G 계열 권고 체계
ㅇ International Telephone Connections and Circuits : G.100–G.199
ㅇ Individual Characteristics of International Carrier Telephone Systems on
Metallic Lines : G.300–G.399
ㅇ General Characteristics of International Carrier Telephone Systems on Radio-
Relay or Satellite Links and Interconnection with Metallic Lines : G.400–G.449
ㅇ Coordination of Radiotelephony and Line Telephony : G.450–G.499
ㅇ Terminal Equipments : G.700–G.799
ㅇ General : G.700–G.709
ㅇ Coding of analogue signals by Pulse Code Modulation : G.710–G.719
ㅇ Coding of analogue signals by methods other than PCM : G.720–G.729
ㅇ Principal characteristics of primary multiplex equipment : G.730–G.739
ㅇ Principal characteristics of second order multiplex equipment : G.740–G.749
ㅇ Principal characteristics of higher order multiplex equipment : G.750–G.759
ㅇ Principal characteristics of transcoder and digital multiplication equipment :
G.760–G.769
ㅇ Operations, administration and maintenance features of transmission equipment :
G.770–G.779
ㅇ Principal characteristics of multiplexing equipment for the synchronous
digital hierarchy : G.780–G.789
ㅇ Other terminal equipment : G.790–G.799
ㅇ Digital Networks : G.800–G.899
ㅇ Digital Sections and Digital Line System : G.900–G.999
3. ITU의 G 계열 주요 권고 표준
ㅇ G.702 : PDH 관련 다양한 비트율(전송속도)에 대한 규정
- `Digital hierarchy bit rates`
ㅇ G.703 : 계층적 디지털 인터페이스의 물리적,전기적 특성
- `Physical/electrical characteristics of hierarchical digital interfaces`
ㅇ G.704 :
- `Synchronous frame structures used at 1544, 6312, 2048, 8448, 44736 kbit/s
hierarchical levels`
ㅇ G.708 : SDH의 NNI
- `Network node interface for the synchronous digital hierarch`
ㅇ G.709 : 광 수송 네트워크 인터페이스 (舊: 동기식 다중화 구조)
- `Interfaces for the optical transport network(OTN)`
ㅇ G.801 : 디지털 전송 모델 (1990)
- `Digital transmission models`
ㅇ G.803 : 동기식 디지털 계위를 기반으로 한 전달망 구조
- `Architecture of transport networks based on the SDH`
ㅇ G.822 : 국제디지털회선에서 제어슬립률 목표
- `Controlled slip rate objectives on an international digital connection`
ㅇ G.957 : 동기식 디지털 계위와 관련있는 장비 및 시스템의 광 인터페이스
- `Optical interfaces for equipments and systems relating to SDH`