This bowl of alphabet soup will be familiar to IT executives and ISP data center staff members. Yet it may not be obvious that all these services must be integrated into a highly scalable plug-in environment that is also flexible in handling aspects such as indexed access, configurable partitions, quotes and aging rules, configurable logging features with automated rollover, and monitoring capabilities. Powerful security and access control must also be inherent characteristics of a messaging server environment. Integrating the messaging server environment with the underlying hardware architecture means getting back to the core issues of sizing and scalability. Whether you're an ISP that is scaling up to meet increasing demands in a more competitive environment or an internal IT executive looking to outsource to an ISP for this purpose, you can be sure that the importance of scalability can never be overestimated.
High availability is another important feature of the messaging architecture.
And it's always a good idea to test your assumptions with a prototype. The main messaging parameters include POP checks per second during peak, messages downloaded per second during peak, and messages delivered per second during peak. Values for these parameters can be calculated from the usage profile of various end user populations. You can determine system throughput requirements with the Mailstone utility, which is included with the Netscape Messaging Server. It measures how systems perform under various load conditions by simulating tasks users perform, determining how much data is moved with each individual request, and measuring how quickly the task is performed.