john83

It is Voice over IP (VOIP) it is not 'Voice over the internet' .

Most startup VOIP providers do not meet Government security standards and therefore cannot be used for any public sector communications.

What are your talking about. Who said it wasn't VOIP and who said anything about voice over the internet.

I simply pointed out that your statement that BT make their Digital Voice a closed system to meet government and security standards is nonsense.

It's just a business decision. It makes support easier. Some providers have followed and others haven't.

I'd love to see something from OFCOM or the government that says otherwise.

The public sector shouldn't be purchasing BT residential connections.
They should be using BT Business, who do VOIP in a different way.

In reply to a post by CplSmudge:

It's supplied to a residential address but charged to a company account.

To put the question more clearly: did you buy a BT Residential product from the BT retail division, or did you buy a BT Business product from BT Business?

BT Business FTTP products are those listed here:
https://business.bt.com/products/broadband-and-inter...

I believe they use TLS on the signalling side of things. Not sure about SRTP.

In reply to a post by Pheasant:

I believe they use TLS on the signalling side of things. Not sure about SRTP.

The likes of Voipfone and Sipgate do not use encryption, so if BT do that could be seen as an advantage.

Maybe. It’s all a bit moot…

For starters I have a feeling BT simply don’t publish any sort of service description or techical spec. - anyone got a link? The only thing to go by is the the vague marketing description and the T&Cs neither of which go to that level of detail or specificity.

Secondly even if they did use SRTP, you could argue that it’s still *not* really an “end-to-end’ encrypted link because ultimately there’s just an analog port on the Smart Hub and from there to any other devices it’s a clear channel.

Finally as this is calling over the public network, the other calling party is probably on an unencrypted channel / endpoint.

Proper end to end call encryption like social media voice apps (Signal, Telegram, WhatsApp, Viber etc) use is only possible in a fully closed-shop / controlled system.

Digital Voice just isn’t that at all.

The BT Digital Voice replaces the PSTN landline service, so I would argue that it is the security of those two that should be compared.

Whilst it is not clear what the security of the Digital Voice consumer service is, there are details of Secure Voice used by the BT Cloud Phone service here.

They might be similar?

Yes in that case with Secure Voice if you are using an IP endpoint (phone) with TLS and SRTP you have encrypted signalling and channel from that phone to the BT core. If the calls all stay on-net with other Secure Voice subscribers (eg like a government department or private company with branch sites) then yes that would be more secure than PSTN.

However for other calls that run outside of the BT core out to the PSTN it is insecure as PSTN is not encrypted.

So effectively one leg of the call is secure.