Phasing out home phones

[#1]

---

@Mr_Paul wrote:

Can anyone advise the technical reason why some kit doesn't work with VOIP?

---

@Mr_Paul 

IANAE, but it may well be due to whether the DTMF signals are sent 'IN-band' or by RFC 2833 signalling.

My guess is you should be OK with your present setup.

See voip dtmf inband for some possible explanations.

[#2]

@RobPN 

Thanks for the reply.

I do know that if you listen across the line whilst the alarm dialler is dialling, you can hear the tones being sent - they sound like any other telephone we have - so I'm guessing that from the links you gave, this is "in band".

The manual for the Grandstream HT801 states:

DTMF Methods
The HT801/HT802 support the following DTMF mode:
• DTMF in-audio
• DTMF via RTP (RFC2833)
• DTMF via SIP INFO
Set priority of DTMF methods according to your preference. This setting should be based on your server
DTMF setting.

What does that BIB mean please?

[#3]

Just a guess from a retired analogue geezer -

Perhaps the alarm dialler looks for -50V and Earth across a copper pair to initiate dialling, which obv wouldn't be there with VOIP.

[#4]

@Mr_Paul 

Just thinking 'outside the box', have you considered swapping the dialler (assuming that it is a separate device/circuit) for a dialler that uses the mobile network ?, e.g. GSM Auto Dialler Mini – 2G & 4G 

A PSTN dialler over VoIP most likely could be made to work, but you'd have to make provision for power cuts, and assumes that your broadband is reliable, and doesn't have 'stalls' (disrupting the VoIP) due to bufferbloat, etc. 

Assuming your alarm system already has a backup battery, then it could also power a GSM dialler, and is likely be more reliable than VoIP over VDSL,  also the alarm system battery should last longer in a power outage than the UPS battery in your FTTC roadside cabinet.

Just a thought !

[#5]

---

@Mr_Paul wrote:

@RobPN 

What does that BIB mean please?

---

Sorry, but my limited experience of changing DTMF settings has usually been when IVR menu options don't work satisfactorily, e.g. with online banking etc.

At a guess it could mean that you set your local DTMF settings to whatever the called system is expecting (or works best with).

No doubt @MisterW could answer your question. 

[#6]

@198kHz 

Thanks for the reply.

That is possible - I will have to search out my earphones with the croc clips so I can listen across the dialler's terminals with it disconnected from the phone line.

Does a VOIP line have any DC conditions on it normally? I'm guessing that adapters such as the Grandstream one have to be able to supply power to connected telephones?

[#7]

@Anonymous

Actually, a GSM dialler was my first thought, though the ones I saw were significantly more expensive than the one you have linked to.

Would a GSM dialler also require an ongoing mobile phone contract, which would be an ongoing additional cost?

The alarm system does have a built in backup battery, and we are currently on FTTC. However, I am not planning on moving to VOIP until our existing Plusnet contract expires in April 2025.

Depending upon when Openreach are saying then that they are going to be fibreing our area, they keep pushing it back, (currently I think it is sometime between now and the end of time!), then I may give up and move to a CityFibre based FTTP provider. FTTP has been available here for about 3-4 years.

[#8]

---

@Mr_Paul wrote:

What does that BIB mean please?

Built-In-Bridge

It appears to be a standard for facilitating VoIP call recording,  on company and call centre phone servers.

.

[#9]

---

@Anonymous wrote:

---

@Mr_Paul wrote:

What does that BIB mean please?

---

@Anonymous 

In the context of the post in question, I took BIB to mean 'Bit In Bold'  

Quote:

Set priority of DTMF methods according to your preference. This setting should be based on your server
DTMF setting.

What does that BIB mean please?

[#10]

Even cheaper - GSM Easy Dialler – 2G  £50 +VAT

[#11]

---

@RobPN wrote:

---

In the context of the post in question, I took BIB to mean 'Bit In Bold'  

I'd previously been looking at VoIP stuff and recalled seeing this - record via BIB utilizing Cisco’s Unified CallManager 

which is something you might expect an alarm service company to be doing with incoming customer's alarm initiated phone calls.

LOL - I couldn't have been more wrong 

[#12]

@Anonymous 

"Even cheaper - GSM Easy Dialler – 2G  £50 +VAT"

Again, won't that involve an ongoing charge for a mobile phone contract?

"I'd previously been looking at VoIP stuff and recalled seeing this - record via BIB utilizing Cisco’s Unified CallManager 

which is something you might expect an alarm service company to be doing with incoming customer's alarm initiated phone calls."

As I mentioned earlier, I installed the alarm myself, and the dialler calls our mobiles then plays a pre-recorded message advising that the alarm has triggered. So, I am my own Alarm Service Company and Alarm Monitoring Centre!

[#13]

The dialler should work fine with an ATA like the HT801. The ATA provides an  FXS, port. This is a port that conveys the FXS interface that delivers dial tone, ringing voltage, and battery power to FXO ( telephone ) devices.

The ATA then converts the dialing action into a SIP INVITE and simulates the ringing. Once the call connects the ATA then digitises the audio into an RTP stream.

[#14]

---

@Mr_Paul wrote:

Again, won't that involve an ongoing charge for a mobile phone contract?

O2 used to do a "123" SIM card, that you put £10 credit on which wouldn't expire.

Similarly GiffGaff PAYG SIMs don't have to have a recurring plan, and will stay alive with a £5 non-expiring top-up.

There must be other non-contract SIMs specifically intended for alarms and IoT devices.

A possible issue with using a phone type SIM, is that you'd probably need to get the alarm to text/call every six months, to ensure the associated mobile number doesn't get deactivated due to lack of use.

[#15]

GiffGaff would probably work well, I have a "backup" phone with essentially idle GiffGaff sim in and just a bit of credit. As for a "keep alive" call/text you'd presumably want to test it every now and again anyway?