The document is part of a series of documents that specify charging functionality and charging management in GSM/UMTS networks. The GSM/UMTS core network charging architecture and principles are specified in
3GPP TS 32.240 
The high level SMS architecture is as defined in 3GPP TS 23.040 .Only the SMS Router, SMS-SC and the IP-SM- GW are within the scope of this specification. The details for the other nodes in the SMS architecture are defined within 3GPP TS 32.250  and 3GPP TS 32.251 .
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