system/config/session.php
driver
Session driver name.
Default value: 'cookie';
storage
Session storage parameter, used by drivers.
Default value: '';
name
Session name. It must contain only alphanumeric characters and underscores. At least one letter must be present.
Default value: 'kohanasession';
validate
Session parameters to validate: user_agent, ip_address, expiration.
Default value: array('user_agent');
encryption
Enable or disable session encryption. Note: this has no effect on the native session driver. Note: the cookie driver always encrypts session data. Set to TRUE for stronger encryption.
Default value: FALSE;
expiration
Session lifetime. Number of seconds that each session will last. A value of 0 will keep the session active until the browser is closed (with a limit of 24h).
Default value: 7200;
regenerate
Number of page loads before the session id is regenerated. A value of 0 will disable automatic session id regeneration.
Default value: 3;
gc_probability
Percentage probability that the gc (garbage collection) routine is started.
Default value: 2;