再问一下关于GPRS计费的问题

爱卫生

是可选的。但可选的不代表不重要。只要是不影响呼叫的正常建立的参数，都是可选的。那个小区信息就是在user location
information里携带的。可参考TS29.060的规范描述：

“The "User Location Information" IE is used to indicate CGI/SAI/RAI of where the MS is currently located.”

爱卫生

关于G-CDR，可以发几个供参考。

1 3GPP TS 32.298 for Release 97, 98, 99, 4, 5, 6, 7 G-CDRs and Release 6, 7 eG-CDRs, Statement of Compliance, Charging Data Record (CDR) parameter description。

2 3GPP TS 32.298 for Release 8 PGW-CDRs, Statement of Compliance, Charging Data Record (CDR) parameter description

3 3GPP TS 32.298 for Release 9 SGW-CDRs, Statement of Compliance, Charging Data Record (CDR) parameter description

4 3GPP TS 32.295, Statement of Compliance, Charging Data Record (CDR) transfer

5 3GPP TS 32.297, Statement of Compliance, Charging Data Record (CDR) file format and transfer

6 3GPP TS 32.251, Statement of Compliance, Packet Switched (PS) domain charging