VoIP Phones - Cisco SPA

Cisco SPA120 & SPA122

• This is similar to the older Linksys PAP2T ATA
• Ensure software is updated, as this does help with the quality of the audio, we upgraded to 1.3.2-XU (014) Jul 2 2013
• Blog post regarding this
• Does seem to work will with the modems on Sky boxes to talk home on.

---

The screenshots here were taken from a SPA112 which was actually set up to give a Sky box a phone line to call home on.

In short, set it up without echo cancellation, a-law only, no fax detect, no jitter adjust (set to high), UK line impedance, zero gain, etc.

PLEASE NOTE: If your line has a noticeable echo, turning on echo cancellation may assist.

Do not use +44 as part of the username, otherwise the device will not register. You must use 0.

View of the 'quick settings'

Line Settings

SIP Settings

• Change RTP Packet Size: to 0.020 (which is 20ms)

Regional Settings

• Change FXS Output gain to -3 if modems have problems
• Change the impedance setting to 370_630|310nF

Firewall & Security

• You will also want to set up firewall rules, as per the VoIP Firewall page.
• Also see the VoIP Security page for information about securing your VoIP service.