请问SGW的一个counter

lily

请问所说的SGW从S1-U口接收的GTP-U数据包的个数和G-PDU包的个数是一个概念么？它们的个数相同么？谢谢

hycl5410

TS 29.274
GTP-PDU: GTP Protocol Data Unit is either a GTP-C Message or a GTP-U Message. GTP-U Message may be either a signalling message across the user plane tunnel, or a G-PDU (see clause 6).
•        Signalling Message: any GTP-PDU (GTP-C or GTP-U) except the G-PDU.
•        G-PDU: GTP user plane message, which carries the original packet (payload). G-PDU consists of GTP-U header and a T-PDU.

• GTP-U Message: GTP user plane message. The user plane messages are used to carry user data packets, and also signalling messages e.g. for path management and error indication. Therefore, GTP-U message consists of GTP-U header, which is followed by either a T-PDU, or zero or more information elements.
  

Signalling Message in GTP-U，最典型的就是GTP链路维护的数据ECHO。
所以一般来说，S1-U口接收的GTP-U数据包的个数 大于 G-PDU包的个数。如果enb和SGW都不开启S1-U GTP链路检测，那么应该可以等于吧。
目前没有想到除了GTP ECHO外S1-U上的信令包（按理S1-U上也可以有error indication，但是没见到过）。另外不确认S1HO时那些通过SGW中转的数据包算不算G-PDU(个人理解应该是算的)。