24.5383GPPEnabling MSGin5G ServiceProtocol specificationRelease 17TS
5.1 MSGin5G Client
An MSGin5G Client acts as client-side functionality for MSGin5G UE configuration, registration and message delivery.
The functionalities of MSGin5G Client include:
a) supporting registration to an MSGin5G Server;
b) supporting configuration required to use MSGin5G Service;
c) constructing MSGin5G message when:
1) requested by an Application Client resides on the same MSGin5G UE or;
2) requested by the Application Client resides on a Constrained UE without MSGin5G Client by acting as a gateway;
d) delivering MSGin5G message payload to the targeted Application Client;
1) directly when the Application Client resides on the same MSGin5G UE or;
2) resides on a Constrained UE without MSGin5G Client by acting as a gateway;
e) exchanging MSGin5G messages with an MSGin5G Server;
f) supporting MSGin5G message segmentation according to service provider’s policy;
g) acting as a relay for MSGin5G Client resides in other UE, which does not have enough capability to communicate with MSGin5G Server (i.e. a Constrained UE), to use MSGin5G Service; and
h) acting as a gateway to handle the registration and deregistration procedures initiated by the application client in a Constrained UE.
5.2 MSGin5G Server
An MSGin5G Server functional entity provides server-side functionality for configuration, registration and message delivery.
The following functionalities of MSGin5G Server need to be considered in current document:
a) exchanging MSGin5G messages with MSGin5G Client;
b) routing MSGin5G messages based on UE Service ID;
c) supporting transport level protocol selection and conversion for exchanging MSGin5G messages with MSGin5G UE;
d) to resolve the MSGin5G Group Service ID to determine the members of the Group specified in 3GPP TS 23.434 ;
e) supporting MSGin5G message segmentation according to service provider’s policy;
f) supporting MSGin5G UE configuration procedures as specified in 3GPP TS 23.434  and 3GPP TS 24.546  or communicating with the SEAL Configuration Management Server to provide MSGin5G configuration data on a UE to be ready for the MSGin5G Service; and
g) managing MSGin5G UE information related to the MSGin5G Service, such as MSGin5G Client availability.