08.143GPPBase Station System (BSS) - Serving GPRS Support Node (SGSN) interfaceGb interface Layer 1General Packet Radio Service (GPRS)Release 1999TS
Refer to 3GPP TS 02.60 .
Refer to 3GPP TS 03.60 .
For the purposes of the present document the following abbreviations apply. Additional applicable abbreviations can be found in 3GPP TS 01.04  and 3GPP TS 03.60 .
DCE Data Circuit-terminating Equipment
DTE Data Terminal Equipment
E1 A four wire symmetrical digital transmission path carrying PCM signal at 2048 kbit/s.
FRF Frame Relay Forum
T1 A four wire symetrical digital transmission path carrying PCM signal at 1544 kbit/s.