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No discussion of messaging management would be complete without touching on topics such as service-level agreements, support, privacy, retention, archiving, appropriate use, naming conventions and chargebacks, to name a few. We'll focus on the most common diagnostic tools and how they function.

Bruce E rnst, software engineering architect at Lotus, defines enterprise messaging management as the "monitoring, operating and configuring of network components directly responsible for messaging." These components include, but are not limited to, messaging applications, message stores and queues, directories, mail-enabled applications and application programming interfaces (APIs), servers, the network backbone, gateways, connectors, hubs, switches, routers, post offices, message transfer agents (MTAs), modems, external connections, communications paths, user agents and workstations. All the possible paths that a message can take between two users, domains, platforms, over the Internet or through a value-added network (VAN) must be investigated carefully and included in the overall architecture.

For every component identified, determine the round-trip delivery time, availability and message-throughput requirement. For example, most organizations mandate that 90 percent of all messages be delivered within 30 min utes. For availability, the system is typically required to be fully operational 99.99 percent of the time. Throughput varies by how many messages the various components in the enterprise messaging system can process in an hour and what is expected by the users. Establishing these requ irements and fulfilling them will provide an early warning detector of system problems, raise morale, meet user and management expectations and enable messaging management to be proactive as well as reactive.

Basically, there are two procedures that provide the information required for taming the messaging chaos and ensuring system health: message tracking and message-system monitoring.

Message Tracking There's no way around it: Message tracking typically is a clumsy and labor-intensive procedure. There are few tools, and most of these are proprietary and do not scale well. The process is complex and doesn't lend itself easily to automation. There are two types of message-tracking systems: e-mail-based and SN MP-based. Message-oriented management is the lowest-common denominator and is used in products such as SoftSwitch Mail Monitor and MailCheck.

Unfortunately, SNMP cannot distinguish between a message and a delivery report, and there is no definition for a probe as there is in X.400. To resolve this issue, a new standard definition for delivery notifications, called the Delivery Status Notification (DSN) protocol and nicknamed Notary, is under development in the Internet community (to read RFC 1864, "An Extensible Message Format for Delivery Status Notifications," see ds.internic.net/rfc/ rfc1894.txt). Notary uses a Multipurpose Internet Mail Extension (MIME) content-type as a delivery report for messages sent to one or more recipients. The report notifies an originator that a message was successfully delivered, delayed or not delivered.

To track a message, it's essential that every message generate a unique message identifier and that all messaging system components are message-tracking-enabled and wer e operational at the time the message in question was sent. Without these crucial pieces, it is extremely difficult and time-consuming to trace a specific message.

Message identifiers are alphanumeric strings generated by the messaging system when a message is sent. Different e-mail system s use different formats for message IDs, which, of course, result in interoperability problems when tracking a message through multiple applications, gateways and hubs. The format for an Exchange message identifier is X.400 address-like. And not only do message identifiers come in different flavors, but during transmission the recipient addresses may be rewritten, so each hop along the way sees a different recipient address.

Message tracking establishes the path a particular message took after being sent, where it is now or what happened to it. In message tracking, the original message, as well as the one that came into the system or traversed out of the system, is identified. By using information in a search, such as the message identifier, sender's name, recipient's name(s), subject, date and/or time, the facts about that errant message can be discovered. The message-tracking utility will respond to a query with the message's history. Tracking also is used for accounting, billing, chargebacks, auditing and verification of electronic commerce transactions.