GPRS data transmission plane

GPRS data transmission plane

Compared with GSM, GPRS reflects the characteristics of group exchange and group transmission, that is, data and signaling are based on a unified transmission platform. As shown in the figure above, the Protocol structures below the transfer layer (LLC) are the same for data and messaging on Several Interfaces passed by data transmission. In GSM, data and signaling are only the same on the physical layer.

GTPs: GPRS protocol.

All PDUS transmitted between gsns should be repackaged by the GTPs, which provide the traffic control function.

UDP/tcp: Transmission Layer Protocol, which establishes a reliable link for end-to-end connections. TCP provides protection and traffic control functions to ensure Data Transmission Accuracy and TCP connection-oriented protocol. UDP is a non-connection-oriented protocol. UDP does not provide error recovery capabilities, and does not care whether packets have been correctly received. It only acts as the sender and receiver of the datagram.

IP: network layer protocol, which is not described here.

L2: data link layer protocol, which can use general Ethernet protocol.

L1: physical layer.

Network Service: the data link layer protocol. It adopts the Frame Relay mode.

Bssgp: This layer includes the network layer and some transport layer functions, mainly to explain the routing information and service quality information.

LLC: Transport Layer Protocol, which provides end-to-end reliable and error-free logical data links.

Sndcp: Performs segmentation and compression of user data for detailed analysis.

Mac: media control is strongly connected and belongs to the link layer protocol.

RLC: Wireless Link Control Sub-layer, which belongs to the link layer and network layer protocols.