Requirements

When designing the new search system, the designers came up with a core set of goals:

1. Users should be able to search not only their emails, but eventually everything stored in the system, including attachments, contacts, calendar events, and task lists.
2. Search should be fast and accurate.
3. Any new emails should be searchable within seconds of arriving in the mailbox.
4. The first version of search will be released to customers who use Noteworthy Webmail; therefore, POP emails downloaded by POP accounts do not need to be indexed.
5. The search system should be easy to scale as our customer base grows.
6. Failover and backup are absolutely required.