- public: true
- Info
- Terminology
- MMSNA: Multimedia Messaging Service Network Architecture
- MSISDN: Mobile Station International Subscriber Directory Number
- MMS User Agent: application on phone that sends and receives SMS and MMS messages
- MM: multimedia message, the thing that is sent by MMS
- What is MMS?
- Can send messages to MSISDNs or Email addresses
- Can recieve messages to MSISDNs or Email addresses
- Most ISPs have a standard email format used to send email to phones
- Most of the MMS spec is just extra stuff that isn't needed for a simple implementation
- really only need MM1 for a client-side implementation
- Sending MMS
- From phone UA
- Basic message sending
- Message metadata
- Priority
- Message class
- Subject
- Address of sender
- Requesting delivery and read status
- Timestamping when message was sent
- Desired delivery time
- Desired expiry time
- Used if the destination can't receive message right away, controls how long provider keeps message around for (if supported)
- Indicate willingness to pay (money) for the next reply
- Indicate lack of willingness to pay for replies
- Request copy be stored in MMBox if any
- normally only stored on the receiving end's side
- Request content not be adapted
- Useful when providers are making undesired adaptations
- Request for sending address to be hidden
- Message is rejected and not sent if this request can't be fufilled
- Across providers
- Relay server
- Outbound MMS to phone
- Relays to receiving MMS server
- Steps
- Assigns ID, communicates ID back to sender
- Waits until the delivery time indicated in the metadata, if supported
- Puts a copy in the sender's MMBox if desired
- Sends message to receiving relay with modifications
- Timestamp could be one from message, or could be overwritten to whatever
- Sending address is set to the real sending address
- but
- Inbound MMS to phone
- Receiving MMS
- Legacy
- Normal
- Retrieval mode
- Automatic
- Content is automatically downloaded in the background
- Manual
- User has to decide to save an image or not
- Useful if user is billed per incoming MMS
- Useful if incoming images are large
- UA may decide what mode to use based on certain factors:
- Roaming status
- Size of message
- Recommendation from provider
- Sender of MMS
- Automatically download messages from trusted senders
- Manually download from known spammers
- Manually download from blocked senders
- Type of message (image, audio, etc.)
- Formats