Obihai OBi110 Andrews & Arnold VoIP Setup
What’s this?
A little back story and terse summary of the settings I am using to enable VoIP (Voice over IP) telephony from my existing Obihai OBi110 bridge unit, so my analogue phones still work without an analogue line any more..
See also: my earlier post on using A&A for a static IP separated from my ISP
TL;DR? config below
The Obihai OBi110
PC-Magazine wrote a review back in 2012 when these were a shiny new toy explaining what they are for: bridging telephone technologies together.
My Current Use
I bought the OBi110 to use as a super configurable call screening device, with a built-in auto-assistant to inform callers that they are being screened and to press a specific DTMF key, or be diverted to a voicemail system on my local server (this bit never happened!). The call screening has been in place for several years, working well, and allowing me to block many nusiance calls.
The Plan
It’s simple - as the OBi110 supports VoIP via the SIP standard, and A&A can cost-effectively port my existing BT landline number to their SIP VoIP service, I just have to figure out the configuration required to make it work. Behind a Network Address Translation (NAT) router. When nobody has ever done this before with an OBi110 (at least not written it up!). Without b0rking my very well known home phone number that I have had for almost 35 years.
The detailed plan to protect my number!
- Buy a temporary test number (they’re super cheap!).
- Use that temporary number to get the OBi110 working with A&A SIP.
- ..or.. if that fails: buy a known-good SIP to Analogue Telephone Adapter (ATA). Get that working.
- Once something is working, port my real number in and switch over to it.
- Release the temporary number.
The side effects
Asking A&A to port my existing number in will have dramtic side effects on my landline services: as this is the only number, BT will assume I no longer want their telephony and issue a PSTN cease on my line, which will also go to my old broadband provider (Plusnet), who will immediately cease their service too. A non-reversible and final cessation of my landline and old broadband.
The Config
By section, top-to-bottom in the side menu. NB: only shows non-default settings
System Management, Network Settings (these are specific to my internal network - adjust for yours!):
| Parameter | Value |
|---|---|
| AddressingType | Static |
| IPAddress | 192.168.0.8 |
| !SubnetMask | 255.255.255.0 |
| DefaultGateway | 192.168.0.1 |
| DNSServer1 | 192.168.0.5 |
| NTPServer1 | 192.168.0.5 |
| LocalTimeZone | GMT+0 |
System Management, Auto Provisioning:
| Parameter | Value |
|---|---|
| ITSP Provisioning/Method | Disabled |
System Management, Device Admin (I collect syslog on my server, you may not want to):
| Parameter | Value |
|---|---|
| AdminPassword | … |
| UserPassword | … |
| Syslog/Server | 192.168.0.5 |
| Syslog/Level | 7 |
Service Providers, ITSP Profile A, General:
| Parameter | Value |
|---|---|
| Name | Andrews & Arnold |
| STUNEnable | Yes |
| STUNServer | stun.aa.net.uk |
Service Providers, ITSP Profile A, SIP:
| Parameter | Value |
|---|---|
| ProxyServer | voiceless.aa.net.uk |
| RegistrarServer | voiceless.aa.net.uk |
| UserAgentDomain | voiceless.aa.net.uk |
NB: Setting a proxy server is against A&A recommendation but OBi110 considers a service disabled
without it, it provides a default if RegistrarServer is not set.
Voice Services, SP1 Service (as above, I collect detailed syslogs, you may not want to):
| Parameter | Value |
|---|---|
| X_RingProfile | B |
| X_SipDebugOption | Log All Except REGISTER Messages |
| AuthUserName | <allocated number> |
| AuthPassword | … |
NB: Ring profile B is for UK ringing tones, which are less weird for us.
Voice Services, OBITALK Service:
| Parameter | Value |
|---|---|
| Enable | No |
Voice Services, Auto Attendant:
| Parameter | Value |
|---|---|
| Enable | No |
Physical Interfaces, PHONE Port:
| Parameter | Value |
|---|---|
| OutboundCallRoute | {([1-9]x?*(Mpli)):pp},{(<#:>|999):pli},{**0:aa},{***:aa2},{(<**1:>(Msp1)):sp1},{(<**2:>(Msp2)):sp2},{(<**8:>(Mli)):li},{(<**9:>(Mpp)):pp},{(Mpli):pli} |
| PrimaryLine | SP1 |
| RingFrequency | 25 |
| CallerIDMethod | FSK(V.23) |
| CallerIDTrigger | After Polarity Reversal |
NB: Outbound call route replaces 911 with 999 and routes to pli instead of li.
NBB: CallerID settings are for my UK, BT provided analogue phones. YMMV.
Physical Interfaces, LINE Port:
| Parameter | Value |
|---|---|
| Enable | No |
The Result
With the above settings, I can dial a standard number (no prefixes) and it calls out on the SP1 SIP service, connects and can send / receive audio. Incoming calls to the authenticated number are routed to the analogue phones, which correctly answer and can send / receive audio. Success!
NB: I can still force use of the PSTN line by using the **8 prefix in the outbound call route.
END.