Re: [stir] [Acme] How Do You Stop Robocalls?

Roman Shpount <> Tue, 13 July 2021 07:07 UTC

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From: Roman Shpount <>
Date: Tue, 13 Jul 2021 03:06:52 -0400
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To: "Olle E. Johansson" <>
Cc: Mary Barnes <>, "" <>, "" <>, "Salz, Rich" <>
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Subject: Re: [stir] [Acme] How Do You Stop Robocalls?
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On Tue, Jul 13, 2021 at 2:33 AM Olle E. Johansson <> wrote:

> 13 juli 2021 kl. 06:58 skrev Roman Shpount <>om>:
>  At the same time, SIP over TLS has many performance and reliability
> issues that would need to be addressed before it is ready for industry-wide
> deployment.
> There’s also a lack of applicable standards for TLS usage, as I’ve pointed
> out a few times, but the working group seems to have no energy to fix. SIP
> over TLS from the SIP phone side requires implementation of SIP outbound,
> which we never successfully tested at any SIPit. I know of a few
> implementations now, but haven’t tested them together.

We have built a SIP Outbound implementation with TLS. It kind of works but
helped us identify plenty of problems both from reliability and scalability
points of view.

In the meantime, I am more concerned with more and more PII being sent in
SIP INVITE, especially with RCD. It might be legally required to encrypt it
when sending such data over the public internet, which would require TLS or
VPN connections for all service providers. Together with increased SIP
INVITE size, TLS essentially becomes the requirement. At this point, I am
more concerned with making service provider to service provider use cases
Roman Shpount