Rich Communication Services (RCS) protocol, aka Joyn

I want to talk about something no one seems to have talked about yet. While I realize that text/voice/video communication is better sent using the IP native [matrix] protocol, especially when E2E encrypted, the Librem phone should still be able to interface with legacy communication protocols.

With that being said, I’m wondering if the Librem’s texting/calling client will also support the “SMS 2.0” standard, RCS, so it won’t be dead on arrival? Even though it’s an oxymoron, RCS will soon supplant SMS as the new, legacy protocol. In addition to many telecommunications companies worldwide, Google is now helping to push for this as a standardization across the industry, and Apple is expected to follow.

http://www.capacitymedia.com/Article/3780333/Industry-expecting-Apple-to-follow-Google-in-backing-rich-messaging

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… which most likely means for the next 10 years nobody will force you to use it. And after all, support is just one software update away, so I wouldn’t worry much about that now.

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This thread is interesting. I had not heard of RCS.

RCS looks like a positive development from the point of view of standardisation – if people use RCS instead of proprietary messengers that can’t have Free Software clients then it becomes less problematic that neither Purism nor the community can develop such clients. This is not as good as a decentralised platform detached from the carrier altogether, but if you’re using carrier services like SMS already, then RCS is probably not a downgrade from that position unless it displaces use of non-carrier-bound services, such as email.

But it looks like it has the potential to be a negative development from the point of view of privacy. The GSMA’s website features a slideshow which highlights “True metrics” and “Read receipts for brands” as features. There are also ‘presence’ features (online/offline status). A Librem 5 RCS implementation would need to offer the user full control over those! I wonder if the design of RCS enables the classic tracking images, as used in HTML-format marketing emails. That could be annoying.

It could be annoying as a user if businesses start sending you massive graphics plastered with their brand identity when a simple SMS would have communicated the same information with less superfluous marketing cruft.

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This sounds awfully familiar.

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I thought the same, but MMS doesn’t (to my knowledge) include group chat and is inflexible about content and layout, so RCS does add novel features.

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Resuscitating this thread as RCS seems to have reached public use here. It’s bringing with it longer SMS-type messages, voice messages and lossless images in messages, if I understood it right - catching up to modern messaging. So, what’s the latest with this on L5 (anybody, any idea?) and is it possible to have it in Chats?

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Assuming XMPP won’t help it get done…

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To my understanding XMPP has nothing to do with SMS-messages - or does it? I’m not referring to similar messaging via other channels but specifically SMS-messages. Not having RCS on L5 in the near future may become similar to L5 only being able to use BT1.0 and not BT5.x or only being able to watch .avi and not anything newer (mkv, h.2xx etc.).

Is RCS compatibility a modem issue (feature) at all?

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Background reading: Rich Communication Services - Wikipedia

Given that Apple just announced that they are rolling over to Google, and will be implementing RCS next year, that means that more or less 100% of smartphones will be supporting RCS. So it becomes more pressing that the Librem 5 have an RCS client.

You would want to check out whether your carrier and the carriers of people you typically communicate with support RCS - because that will determine who has access to your communication (and potentially whether any third parties have access to your communication).

The inconsistent state of end-to-end encryption with RCS looks problematic.

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Welp, they got E2E encryption figured out, even between IOS and droid phones: RCS Encryption: A Leap Towards Secure and Interoperable Messaging  - Newsroom Even more worried this becomes a missing feature with linux mobile in general [ping @linmob FYI]. It seems to be becoming the next generation in the line (SMS → MMS → RCS).

It would be good to have this as it would be a needed security upgrade (in addition to usability, although not the most secure nor private if you compare to other protocols). If you are using SMS based MFA, it may get hardened to RCS and stop working on linux phones (SMS MFA with security code is the most vulnerable, unlike one time pad type codes via SMS). That would effect a lot of essential services. It has been a whishlist ticket in Chatty for years, but no mention if it’s ever getting any love. I wonder if it could have some attention, now that phosh is in good order [adding a ping to @guido.gunther as the ticket owner]. To be fair, other open messaging apps are scrambling too (for example on F-droid side).

For those more interested on the scale of the task, Google dev docs: RCS Business Messaging 작동 방식  |  RCS Business Messaging Developer Docs  |  Google for Developers A quote from Ubports blog from last year: “Most providers use a Google RCS server. We could in theory set up our own. Apple is moving into that sphere now too. It would be possible for us to use vendor supplied binaries but like VoLTE solutions, they would be device specific. Compared with VoLTE it is much less complex so perhaps there is potential there. It is a specialist area, so if you have knowledge or know someone who does, please contact us. Marius did a quick search and found that Google have provided packages in Node.js and Python.” [so, acceptably open version sounds doable]

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The repo you linked to is archived. The current one is Rich Communications Services (RCS) messaging support (#219) · Issues · World / Chatty · GitLab which has some more recent activity and details how this could move forward.

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