This is the twelfth in a series of messages describing new features in Isode R14.4, scheduled to ship in April 2009. You can see all of the messages on this blog relating to R14.4 by clicking on this link
R14.4 M-Switch adds the capability to use customer or partner provided capabilities to check and convert Internet messages. Although M-Switch provides a comprehensive range of checking and conversion capabilities, there will sometimes be customer requirements that go beyond this. R14.4 enables this by use of a new protocol called CCCP (Content Checking and Conversion Protocol). The CCCP specification is available here.
M-Switch uses CCCP to provide information to a customer developed CCCP server, that performs checking and conversion of messages. CCCP is a simple text encoded protocol with an encoding approach aligned with the IMAP protocol. CCCP enables the following functionality to be provided:
- Recipient changing (can be regarded as re-writing or redirect).
- Sender re-write.
- Recipient expansion (so the CCCP server can implement simple lists).
- Content conversion. The CCCP server may provide back modified messages, and different copies can be assigned to different recipients.
- For each recipient, message can be non-delivered, discarded, or quarantined (the CCCP requests M-Switch to perform the action).
These features allow a CCCP server to perform a wide range of address and content checking and conversion functions. The client/server architecture gives a number of advantages:
- CCCP processing is applied to stored messages, so this is completely transparent to external message transfer.
- Parallel processing means that slow CCCP processing of one message (e.g., taking human intervention) will not delay other message processing.
- Conversion and Checking is cleanly decoupled from M-Switch.
- For large deployments, M-Switch and CCCP servers can be independently horizontally scaled.
M-Switch provides flexible use of CCCP, so that multiple CCCP channels can be configured to provide different conversions for different message flows. CCCP enables a wide range of conversion capabilities for different markets, and Isode is happy to work with any partner or customer to develop new CCCP servers.