Bearer +Mobility Policy Plug-in

The bearer mobility policy plug-in enables email server MTMs (POP3, IMAP4, +or SMTP) to do the following tasks, provided bearer mobility is set at the +client-side:

Check for the bearer +that is currently available.
Register for notifications +when a new bearer becomes available.
Handle notifications +of availability of new bearers, and respond with acceptance or rejection of +the new bearer.
Handle notifications +that a bearer change has occurred, and initiate socket re-establishment.

The bearer mobility policy plug-in interface allows customisation of the +migration behaviour of email accounts. It consists of an ECOM interface class, CImMobilityPolicyPlugin and +a call-back class, MImMobilityPolicyHandler which allows +the plug-in to issue policy decisions on individual mobility events.

Description

There are two components (APIs) in +the bearer mobility policy plug-in: policy plug-in and policy handler. +A default policy plug-in implementation is provided, which can be overridden.

The +policy handler can set policies on for the preferred bearer to accept or reject, +when the bearer is available. Based on the policy that you set, the migration +to the preferred bearer is decided. If you have set the policy to accept the +preferred bearer, then the policy plug-in receives notification when a switch +to a new bearer occurs, or when the current connection is lost. For graphical +illustration of the architecture, see Architecture.

API overview

The CImMobilityPolicyPlugin class +allows the plug-in to be notified about mobility events. The mobility manager +and server MTMs do not attempt to perform a migration until the policy plug-in +has issued a response to a notification.

The MImMobilityPolicyHandler class +allows the bearer mobility policy plug-in to provide the decision on whether +to accept or reject a migration.

The bearer mobility policy +plug-in (CImMobilityPolicyPlugin) implements the following +functions:

PreferredCarrierAvailable()
Cancel()
MigrationComplete()

Responses to the preferred carrier interface are made +through the MImMobilityPolicyHandler class, which has the +following functions:

AcceptNewCarrier()

If +a migration is accepted, this function provides the following options for +managing client-requested operations that may be in progress.
- The client-requested +operation is immediately stopped the current outstanding server command is +cancelled. The open sockets are closed, and migration is initiated.
- The client-requested +operation continues until the data does not need to be re-sent or re-received +after migration. For example, if fetching several messages, the current message +will be allowed to complete.
- The client-requested +operation is allowed complete before migration is accepted.
IgnoreNewCarrier()

+ Bearer plug-in class diagram + +