Linksys SPA9000 Administration Guide

Linksys Voice System Administration Guide 44
Configuring SIP Timer Values
Configuring the SPA9000 for ITSP Interoperability
Configuring SIP Timer Values
The SPA9000 is configured with default timer values that should be adequate in most
circumstances. However, you can adjust the SIP timer values as needed to ensure
interoperability with your ISTP. For example, if SIP requests are returned with an “invalid
certificate” message, you may need to enter a longer SIP T1 retry value.
To view the default settings or to make changes, open the Voice > SIP page, and scroll down to
the SIP Timer Values section. For field descriptions, see ”SIP Timer Values (sec) section,” on
page 161.

Linksys SPA9000 Specifications

Physical Interfaces

Ethernet ports	2 10/100BaseT RJ-45
Phone ports	2 RJ-11 FXS
Ring voltage	40-55 VRMS
Ring frequency	10 Hz - 40 Hz
Maximum ringer load	3 REN

Power

On-hook voltage	-50 V NOMINAL
Off-hook current	25 mA min
Terminating impedance	Configurable, including 600 ohms