Configuration tips for connecting the Cisco SPA8000 to your analog telephone system or fax machine.

This procedure describes most of the configuration needed to connect the Cisco SPA8000 to an older analog telephone pbx system, or any telephone system with analog POTS lines that do not have built-in SIP trunk capability.  It also works for connecting analog trunk adapters (ATA) to Fax machines, but some additional configuration is required … it’s included below.

With the Cisco SPA8000 you can connect virtual ANY telephone system to SIP Trunks.  Connecting your old phone system to SIP trunks may save you money, and will add features to your old phone system you may not be able to add any other way – including menus, voicemail-to-email, and voicemail transcription.

You cannot reliably connect credit card processing machines, alarm systems, modems, and the like to VoIP SIP trunks through ATAs.  You are better off using good old fashioned copper POTS lines for that.

Need to connect SIP Trunks to an older analog phone system?  
We can provide you with trunks that work  great with this procedure,
and can pre-configure the device for you when you place your order with us.
Give us a call if we can help 610-441-7222.

Configuration Guide

Tested connecting back to our SIP Trunking service using Cisco SPA firmware 6.1.12 SR1

In Admin, Advanced, Regional
  1. Set ring waveform to Sinusoid
  2. Set CPC duration to 0.8
  3. Set Time Zone accordingly (e.g., Eastern = GMT-05:00)
  4. Set Daylight Savings Time Rule to:
For each Trunk Group (T1, T2, T3, T4)
  1. Set Line Enable to No
For each Line (L1, L2, …, L8)
  1. Set Line Enable to Yes/No accordingly
  2. Set NAT Mapping Enable = yes
  3. Set NAT Keep Alive Msg = $OPTIONS
  4. Set NAT Keep Alive Enable = yes
  5. Set NAT Keep Alive Dest = $PROXY
  6. Set Proxy to your SIP Server
  7. Set Display Name to “Line 1”, “Line 2”, etc.
  8. Set User ID to the extension number or line number in the SIP server you’re receiving service from
  9. Set Use Auth ID = yes
  10. Enter your SIP Proxy username in Auth ID
  11. Enter you SIP Proxy password in Password
  12. Set Call Waiting Serv = no
  13. Set Three Way Call Serv = no
  14. Set your dial plan to:
    ( [23456789]11 | *xxx. | [2-9]xx[2-9]xxxxxxS0 | 1[2-9]xx[2-9]xxxxxxS0 | 011xxxxxxx. | [#*x][*x][*x][*x][*x][*x][*x][*x][*x][*x][*x][*x]. )
Connecting your lines to a Fax machine?

If you are connecting your SPA8000 to a fax machine, you must also perform these steps.

In the Network Settings section …

  1. Set Jitter Buffer Adjustment = disable

In the Audio Configuration section …

  1. Set preferred codec = G711a
  2. Set Second preferred codec = Unspecified
  3. Set Third preferred codec = Unspecified
  4. Set Use Pref Codec Only = yes
  5. Set Silence Supp Enable = no
  6. Set Echo Canc Enable = no
  7. Set Fax Passthru Codec = G711a

On your fax machine, you must also:

  1. Set the resolution to Standard
  2. Set the Baud rate to 9,600
  3. Turn Error Correction Mode (ECM) to ‘off’

Cisco SPA8000 backup and restore

To backup your configuration, navigate your browser to:


Save the file.  You will need it later to restore.  It does not contain any passwords – when you restore, you’ll need to manually enter those, or you can use a tool like the Notepad++ Text Editor to edit the XML configuration file and add-in the passwords.  Be careful!  If you lose the file to another person, they can use the file to access your VoIP service, and you might find yourself the victim to toll fraud.

To restore your configuration, first install Solarwinds TFTP server on your computer and make sure that your windows firewall has UDP port 69 unblocked.

Next, copy your config.xml file into the C:\TFTP-Root\ directory that SolarWinds TFTP server creates for you.

Last, tell your Cisco SPA8000 to load the config file by navigating your web browser to: