从r99版本到R4版本再到IMS，电信网络的核心网架构发生了较大的变化。

With version from R99 to R4 then to IMS, the Core Network architecture has been changed along.

youdao

从r99版本到R4版本再到IMS，电信网络的核心网架构发生了较大的变化。

With version from R99 to R4 then to IMS, the Core Network architecture has been changed along.

youdao