| Interface | Fonction 1 | Fonction 2 | Protocoles |
|---|---|---|---|
| Um | Mobile | BTS | GSM Air Interface |
| Abis | BTS | BSC | LAPD |
| A | BSC | MSC | BSSAP, MTP |
| Gb | BSC | SGSN | BSSGP, NS |
| Gr | SGSN | HLR | MAP |
| Gd | GMLC | HLR | MAP |
| Gf | SGSN | EIR | MAP |
| Gi | GGSN | Internet | IP, PPP |
| Interface | Fonction 1 | Fonction 2 | Protocoles |
|---|---|---|---|
| Um | Mobile | BTS | GSM Air Interface |
| Abis | BTS | BSC | LAPD |
| A | BSC | MSC | BSSAP, MTP |
| Gb | BSC | SGSN | BSSGP, NS |
| Gr | SGSN | HLR | MAP |
| Gd | GMLC | HLR | MAP |
| Gf | SGSN | EIR | MAP |
| Gi | GGSN | Internet | IP, PPP |