In-depth research on GPRS route management

At present, GPRS routing is widely used and promotes the development of wireless routing. So I have studied the knowledge about GPRS Routing Management and will share it with you here. GPRS route management refers to how the GPRS network can address and establish a data transmission route. GPRS route management is manifested in the following three aspects: the establishment of GPRS route for transmitting data from the Mobile Station, the establishment of route for receiving data from the mobile station, and the establishment of data route when the mobile station is roaming.

In the first case, when the mobile station generates a PDU group data unit, the PDU is processed by the SNDC layer and is called an SNDC data unit. Then, the LLC layer processes the SGSN sent to the mobile station in the GSM network through the air interface. SGSN sends data to GGSN. GGSN uninstalls the received message and converts it to a PSPDN-type PDU transmitted in the public data network. To improve transmission efficiency and ensure data transmission security, data on the air interface can be compressed and encrypted.

In the second case, a public data network user transfers data to the mobile station. First, establish a GPRS route between the data network and GGSN through the standard protocol of the data network. The data unit sent by the data network user, such as the PDU in PSPDN). The data unit PDU is sent to the GGSN through the established GPRS route. The GGSN then sends the pdu to the sgsn where the mobile station is located. The GSN encapsulates the PDU into an SNDC data unit, processes it as an LLC frame unit through the LLC layer, and finally sends it to the mobile station through the air interface.

The third case is that a data network user transfers data to a roaming mobile user. In this case, the data transmission route is used. The data must go through the GGSN of the primary location and then be sent to mobile user. The air port-based channel constitutes the channel composition of the GPRS route air interface as follows:

◆ PDTCHPachet Data Traffic Channe1), group Data business channel. This channel is used to transmit the GPRS grouped data of the air interface.
◆ PPCHPacket Paging Channe1). The group Paging channel PPCH is used to call the GPRS called user.
◆ PRACHPacket Randem Access Channel), grouped by random Access Channel. GPRS users send channel requests to the base station through PRACH.
◆ PAGCHPacket Access Grant Channel), the Group receiver response Channel. PAGCH is a response channel that responds to PRACH.
◆ PACCHPacket Asscrchted Control Channel), group with the path Control Channel. This channel is used to transmit signals that implement GPRS routing data services.