| CN | CN1 | CN2 | CN3 | CN4 | CN5 |
| CT | CT1 | CT3 | CT4 | CT5 | CT6 |
| GERAN | GERAN1 | GERAN2 | GERAN3 | GERAN4 | GERAN5 |
| RAN | RAN1 | RAN2 | RAN3 | RAN4 | RAN5 |
| SA | SA1 | SA2 | SA3 | SA4 | SA5 |
| T | T1 | T2 | T3 |

TSG SA WG2 (Architecture)

Overview:

TSG SA WG2 Architecture is in charge of developing the Stage 2 of the 3GPP network. Based on the services requirements elaborated by SA1, SA2 identifies the main functions and entities of the network, how these entities are linked to each other and the information they exchange. The output of SA2 is used as input by the groups in charge of the definition of the precise format of messages in Stage 3 (Stage 2 for the Radio Access Network is  under TSG RAN's responsibility). The group has a system-wide view, and decides on how new functions integrate with the existing network entities.