SMS +MTM Overview

SMS MTM provides APIs for sending SMS text messages. This section provides +an overview of the SMS MTM component.

Description

The Messaging Application module provides +a SMS MTM for handling SMS messages in the Message Store. For further SMS +support available the Symbian platform, see Cellular +Baseband Services Guide documentation.

Supported functionality

SMS +MTM provides functionality to create, store and retrieve an SMS message entry +in the Message Store, send an SMS, reply to a received SMS and forward existing +SMS. A reply to a received SMS may include the original message text, including +any EMS components.

SMS that are received by SMS MTM are stored in +the Message Store. The type and class of the received SMS affects the storage +of a message. All received class 2 SMS are stored in a non-Symbian platform +store.

Storing SMS

SMS messages that are received by +SMS MTM are stored in both the Message Store and a non-Symbian platform store. +Messages can be moved, copied to, from the non-Symbian platform store and +the Message Store. The non-Symbian platform store can be enumerated so that +its contents can be reflected in the folder in the Message Store, except any +of the standard folders (for example, the global inbox).

The type +and class of the received SMS affects message storage. All received class +2 SMS message are stored in the class 2 folder in a non-Symbian platform store. +The class 2 folder is a configurable location in the Message Store and may +be set to be the global inbox. All received non-class 2 SMS messages are stored +in the global inbox folder of the Message Store.

Sending SMS

SMS +MTM can send the message immediately or schedule it for a specific time. Before +SMS MTM sends an SMS, it checks the global outbox in the Message Store for +any SMS that are waiting to be sent (these can also be scheduled for sending). +If an SMS failed to be sent, then the MTM may re-schedule that SMS to be sent +at a later time. A re-schedule is configurable against the failure error code. +The schedule send functionality handles this configuration. A SMS that is +successfully sent is moved to the sent folder in the Message Store by SMS +MTM.

This MTM supports multiple recipients for an SMS message. An +outgoing SMS message may have multiple recipients. When this message is being +sent, one message is sent for each recipient.

BIO messages

SMS +MTM is aware of BIO messages and uses the BIO Framework to tag SMS with the +appropriate BIO type. This includes support for WAP messages.

Unsupported +functionality

SMS MTM does not support sending and receiving OTA +(Over The Air) SMS messages.

Architecture

The Messaging Middleware architecture +defines a framework in which modules (MTMs) can be implemented that provide +support for particular messaging protocols. A client MTM provides the API +for application engines to use the protocol. SMS MTM API provides the client +MTM API, server MTM API, and supporting classes for SMS.

SMS MTM integrates +SMS into the Messaging architecture, so that SMS can be used by a messaging +client program in a similar way to other message types such as email. SMS +MTM uses the SMS interface provided by the Telephony sub-system. This provides +support for 7, 8, and 16-bit text messages, and message concatenation.

The +following figure shows the SMS architecture that Symbian has implemented in +the Symbian platform.

+ SMS MTM architecture + +

SMS Client MTM

The SMS Client MTM implements the +standard set of Client +MTM APIs described in Client +MTM. In addition, it provides the following functionality:

Access to the CSmsHeader object +that is used to represent the SMS message.
Access to the SMS settings +stored in the associated SMS service centre.
Provides the APIs required +by SendAs to allow SendAs to create SMS, including setting the BIO type message +to allow clients of SendAs to send BIO messages, such as vCards and vCals. +The data of the BIO message is stored in the body text of the SMS.
Simple check for valid +SMS addresses; an SMS address is considered valid if it contains at least +one digit.
Reading and writing +SIM parameters.

MS receiving is normally done automatically by the Cellular Baseband +and messaging components, with received SMS messages placed in the Inbox. +Generic message receiving operations are not supported by the MTM. Also, UI +functionality, such as SMS message viewing and editing, is not provided by +Symbian platform.

The SMS Client MTM class is CSmsClientMtm.

SMS Server MTM

SMS +Server MTM implements the Server-side +MTM interface, and primarily provides functionality to handle requests +from the client MTM to send SMS messages. Incoming SMS messages are handled +by a group of components called SMS watchers.

These components provide +a layer over the SMS support provided in the Narrow Band Protocols Stack subsystem. +This has SMS stacks for GSM which offer an encapsulation of an SMS message, +together with the ability to send and receive messages. At the lowest level, +below the SMS stacks, is the ETel multimode API, which provides low-level +access to the phone drivers.

The SMS Server MTM provides access to +messages under remote services. It is loaded in the Message Server’s process +space and handles the following tasks:

Connecting to remote +servers to handle updating the cache of SMS messages.
Sending messages that +are copied to remote services when messages are copied to a remote service.

The +SMS Server MTM handles sending of SMS and WAP messages through the SMS stack +and the WAP stack respectively. To support this, it implements the CBaseServerMtm::CopyFromLocal() function +inherited from the Server +MTM base class. It implements this for sending SMS and moving the successfully +sent messages to the Sent folder. When sending the SMS, the Server +MTM checks the BIO type of the message and uses the BIO database to check +the transport type for the BIO message. The MTM supports ENbs that +is sent through the SMS stack and EWap, EWapSecure that +are sent through the WAP stack. The MTM does not support EWsp or EWspSecure although +the watchers do support receiving them.
Scheduling messages

The +SMS Server MTM implements scheduled sending API by sub-classing from the Schedule +send Server MTM. It accepts requests from client applications either through +the SMS Client MTM's CBaseMtm::InvokeAsyncFunctionL() API +or through the CMsvSession::TransferCommand() API to schedule +messages to be sent or to delete existing schedules. When it receives a request +to schedule a message, it packages the command and uses the Scheduled Send +functionality to request that the task scheduler ask it to send the messages +at a future point in time.
Managing phone store

The +phone store is a storage for SMS outside the Message Store. For example, for +GSM phones it is the SIM. The SMS Server MTM accepts requests from +client applications to copy or move messages to and from the SIM and delete +messages from the SIM. For example, when copying to the SIM, it packages SMS +and passes it to the SMS stack with a request to write it to the SIM. If the +class2 folder is set in the SMS settings class, the Server MTM copies the +SMS to the SIM and then updates the SMS in the message store. The Server MTM +also provides the details of the space used to store on the SIM and the reason +for storing on the SIM.
Providing SIM parameters

The +Server MTM provides functions to read and write SIM parameters.

The SMS Server MTM class is CSmsServerMtm.

SMS +Utilities

SMS Utilities provide the following:

Classes to represent +and store SMS (CSmsHeader), and SMS settings (CSmsSettings, CSmsMessageSettings) +and a SMS number (CSmsNumber).
Functions to generate +descriptions and details fields to store with SMS. The details includes decoding +special messages (such as, message indication and status report messages), +reading resource file for descriptions strings of special messages, and using +the contacts database to replace phone numbers with names.
Function to validate +a GSM number.
Mode to find the TMsvId of +the SMS service entry.

SMS Watchers

SMS Watchers are made up of two watchers, +the nbswatcher.dll and the wapwatcher.dll, +and some common base classes in biowatcher.dll. The watchers +listen for incoming messages from the SMS Stack, part of Cellular Baseband +Services, and the WAP stack, part of High-level Internet Protocols.

SMS +Stack

SMS Stack is one of a number of protocol stacks that is +supported by the ESock Server client-server framework. The SMS Stack’s principal +clients are the messaging applications, WAP Stack and third party applications. +The Messaging Application and the third party applications access the stack +as clients of the ESock Server, while the WAP Stack accesses directly the +SMS Stack. For more information on SMS Stack, see SMS +Stack for GSM Networks.

SMS service settings

Settings +for SMS connections, such as service centre addresses, are stored in the Message +Store (CMsvStore) for the SMS service entry. Encapsulation +of service settings is provided by CSmsSettings.

Progress +information

The progress information can be obtained for messaging +operations. For SMS operations, progress information includes such things +as type of operation, and number of messages processed. Progress information +is provided by TSmsProgress.

APIs + +

The following are the important classes for SMS Client MTM:

+ + + +

Class

Purpose

+ + +

CSmsClientMtm

Implements the messaging architecture client MTM interface for SMS. +It allows messages to be created, replied to, and forwarded, and MTM-specific +commands to be given.

It provides an accessor function SmsHeader() to +get the CSmsHeader for a message.

+ + +

CSmsHeader

Encapsulates an SMS message in a message store.

It provides +information about message recipients as an array of CSmsNumber objects, +and access to the family of classes derived from TMsvMessageBio, +which allow fields of a message to be set and accessed.

For compatibility +with the API of the v8 (GSM only) SMS MTM, it also provides access to the +GSM SMS stack's message class CSmsMessage.

+ + +

TMsvMessageGsm

Provides access to GSM-specific fields.

+ + +

TMsvSmsEntry

Provides a specialisation of the message server index class TMsvEntry for +SMS message entries.

Putting selected SMS-specific fields in the index +entry allows message clients to quickly get important message properties without +having to create a message object.

+ + +

CSmsNumber

Encapsulates recipient information for an SMS message.

+ + +

CSmsSettings

Defines settings for the SMS service.

It contains some GSM-specific +functions to maintain compability with the GSM SMS MTM.

It also provides +access to CSmsMessageSettingsProxy for outgoing message +defaults.

+ + +

CSmsAccount

Stores SMS service and Schedule Send settings to Central Repository.

+ + +

CSmsServiceCenter

Used to store Service Centre numbers and their associated name.

+ + + +