Configure SIP Registration Control

SIP Registration Control

Expires Override

Allows the device to alter the “expires” values in the REGISTER message and the response to this message. If these fields are disabled, the expires values are not altered.

Enable Phone Expires Override

Select the checkbox to override the Registration expiry interval sent to the phone with the value given in the next field.

Phone Expires Override

Enter the number of seconds that a phone considers a registration valid. This value replaces the value given by the SIP server in the response to the REGISTER message. The phone sends the next registration before this time has passed, therefore speeding up the rate at which the phone sends registrations.

Select the checkbox to enable softswitch expires override checkbox.

Softswitch/IP PBX Expires Override

Specifies the number of seconds that the SIP server considers a registration valid:

• Phone Expires Override—Specifies the number of seconds that a phone should consider a registration valid. This value replaces the value given by the SIP server in the response to the REGISTER message. The phone sends the next registration before this time has passed. Use to speed up the rate at which the phone sends registrations.

• Softswitch Expires Override—Specifies the number of seconds that the SIP server should consider a registration valid. This value replaces the value given by the phone in the REGISTER message. This value should be higher than the rate-pacing value so that the SIP server does not consider the phone registration to have expired.

Registration Rate-Pacing

Specifies the rate at which registration messages are forwarded to the Softswitch/IP PBX.

Rate-Pacing behavior

Choose a mode from the Rate-Pacing behavior drop-down list:

• None—No rate pacing is applied.

• SoftSwitch/IP PBX provided value—Rate of pace is calculated from the value provided by the SIP server.

• Configured value—Rate of pace is configured.

For example, if you choose the SoftSwitch/IP PBX provided value:

Pace Time = SIP server provided value - 2 * Phone Expires Override

This ensures that the system allows registration to the SIP server before the registration has expired.

Rate-Pacing interval

Enter the number of seconds to wait before forwarding a register message from one phone to the SIP server.

If the Phone Expires Override field is set to a low value, the number of registration messages may overload the SIP server. To avoid this, set this field to the number of seconds to wait before forwarding a register message from one phone to the SIP server. Any register messages received before this time is answered locally by the system.

For example, you may set the Phone Expires Override value to 60 and the Registration Rate-Pacing value to 1800 to have the phone register to the system every minute, but only let a register message through to the SIP server every 30 minutes.