Implementation Guide › Capacity Planning › Estimate a Peak Authentication Rate

Estimate a Peak Authentication Rate

What is the peak authentication rate for the application?

The peak authentication rate is based on the sustained authentication rate, specifically, when and at what rate the system is operating at peak levels. Estimating the peak authentication rate is the process of identifying when the system is servicing the highest level of authentication requests.

When estimating the peak authentication rate, we recommend using the metrics you gathered when determining the sustained authentication rate to determine:

• The hour when the system is servicing the highest number of authentication requests
• The approximate number of authentication requests that occur during this period

The following figure is an example of these metrics:

Identifying these metrics helps you to estimate the number of authentication requests, per second, that SiteMinder must service to maintain the peak rate at which users authenticate, which the following represents:

(authentication_load x percentage_of_transactions) / number_of_hours / 3600 = peak_authentication_rate

Note: This rate is based on the single busiest hour. There can be periods when the peak authentication rate exceeds the hourly calculation.

• authentication_load

  Represents the number of daily authentications for the application.

• percentage_of_transactions

  Represents the percentage of transactions that occur when the system is operating at peak levels.

• number_of_hours

  Represents the number of hours in which the system operates at peak levels.

  Note: 3,600 represents the number of seconds in an hour.

• peak_authentication_rate

  Represents the peak authentication rate for the application.

Example: Estimate the Peak Authentication Rate

The company has determined that their portal application has a daily authentication load of 88,000 logins. System activity reports detail that during the single busiest hour of the day 18,000 authentication requests occur. This number represents approximately 20 percent of the authentication load:

18,000 / 1 / 3600 = 5 authentications per second

The portal application has a peak authentication rate of five authentications per second.

Note: This example is based on the single busiest hour. There can be periods when the peak authentication rate during the hour exceeds five authentications per second.