OMA Instant Messaging Media Types

When applying the OMA Instant Messaging communication service on 3GPP enabled terminals then an interoperable baseline set of media types must be supported by the mobile terminal. This set of media types is defined in 3GPP TS26.141 [29] and contains quite a large number of media types. But it should be pointed out that the mobile terminal may also support media types other than the ones in the baseline set. The design criterion used when developing this baseline set of media types was to maximize the technology reuse of other services like MMS and the streaming service defined in 3GPP. The IM service should be able to provide the service of sending/receiving the following media types in a 3GPP environment.

IM Client A home network

IM Client B home network

IM Client A IM user A send a message

IMS Core A

IM Server A | (Controlling & Participating)

IM Server B (Participating)

IMS Core B

IM Client B

Acknowledgement that message is delivered <-

-SIP MESSAGE I

-SIP MESSAGE I

SIP MESSAGE -

SIP 2GG OK

SIP MESSAGE -

SIP MESSAGE--SIP MESSAGE SIP 2GG OK-SIP 2GG OK-

Message content readable for IM user B

IM Client A home network

IM Client A IM user A send a message ^

IMS Core A

larger than 1300 bytes

The actual message Is sent here

Acknowledgement that message is delivered <-

IM Server A | (Controlling & Participating)

IM Client B home network

IM Server B (Participating)

IMS Core B

IM Client B

-SIP invite --SIP INVITE-

-SIP 2GG OK--SIP 2GG OK— SIP ACK — — SIP ACK —

-SIP INVITE-SIP 2GG OK-

Message content readable for IM _user B ^

SIP 2GG OK

SIP 2GG OK

SIP INVITE

SIP 2GG OK

SIP ACK

SIP ACK

Figure 8.14: IM flows. (a) Pager mode messaging using the SIP MESSAGE method. (b) Pager mode messaging using MSRP.

• Text: Plain text, any character encoding that contains a subset of Unicode logical characters can be used.

• Still image: The JPEG compression and JFIF file format are used.

• Bitmap graphics: The GIF and PNG formats are used.

• Speech: The AMR narrowband and AMR wideband speech codecs are used.

• Audio: The audio codecs AAC+ and extended AMR-WB are supported.

• Video: Certain profiles of the video codecs H.263, MPEG-4 and H.264 are supported.

• Synthetic audio: The Scalable Polyphony MIDI content format is supported.

• Vector graphics: The Scalable Vector Graphics (SVG) Tiny format and the EMCAScript are supported.

• Media synchronization: A subset of SMIL 2.0 is used for media synchronization.

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