Maximum number of concurrent sessions defines how many connected users a Portal Server deployment can handle.
To calculate the maximum number of concurrent sessions, use this formula:
maximum number of concurrent sessions = expected percent of users online * user base
To identify the size of the user base or pool of potential users for an enterprise portal, here are some suggestions:
Identify only users who are active. Do not include users who are, for example, away on vacation, or on leave.
Use a finite figure for user base. For an anonymous portal, estimate this number conservatively.
Study access logs.
Identify the geographic locations of your user base.
Remember what your business plan states regarding who your users are.