Apple is finally bringing RCS messaging to the iPhone

> There is talk that Google's got some kind of extension that adds E2EE to RCS but others will be well informed on it and can add to my message.

It’s not just talk, but it’s locked down. Google’s huge PR campaign backing RCS has been very impressive at getting people to conflate the two but basically they have an RCS extension implementing the Signal protocol which theoretically could be implemented by anyone but it depends on Google’s key exchange servers which are restricted to their own proprietary app – even third-party Android developers are blocked.

It’s a PR masterwork, really. They’re honest on the technical white paper:

> E2EE is implemented in the Messages client, so both clients in a conversation must use Messages, otherwise the conversation becomes unencrypted RCS. In rare situations where the conversation starts as E2EE, then one of the clients migrates to a different RCS client or an older Messages client that does not support E2EE, Messages might be unable to detect the change immediately. If the Messages user sends a new message, it’s still E2EE, however the recipient client may render the encrypted base64 payload directly as message content.

https://www.gstatic.com/messages/papers/messages_e2ee.pdf

Meanwhile, the far more widely read marketing pages they actually advertise say things like this:

> SMS and MMS don’t support end-to-end encryption, which means your messages are not as secure.

https://www.android.com/get-the-message/

They already added e2ee. If I long-press a message right now and press "show more information" it says "Message with RCS with end-to-end encryption".

Their own documentation claims as much: https://support.google.com/messages/answer/10252671?hl=en

But it is the google-only RCS. If your provider have their own RCS implementation, tough luck.

> it's always a pain to figure out why a group chat is showing up green all of a sudden; you can't tell who brought the Android to the party.

Genuinely curious -- why do you feel it's necessary to figure that out at all?

> That's why it's always a pain to figure out why a group chat is showing up green all of a sudden; you can't tell who brought the Android to the party.

Or as the rest of the world would describe it: That's why it's always a pain including Americans in a group chat – they usually don't have WhatsApp :)

Devil's advocate: that was an intentional design choice to incite even more user hate against Android users and build Apple cult mentality. Users will subconsciously assign the blame for their frustration of figuring out who the Android user is, to the Android user, rather than to Apple who is the real culprit.

That’s cuz they’re not. Nobody is. RCS is a crap standard, but it is a crap standard that the PRC, one of Apple’s larger markets, is requiring in new handsets going forward (something that The Verge reporter overlooked). I’m still curious what the compatibility story even is given Google has their own encryption standard but Apple is sticking to the GSMA spec and in their original announcement said they were going to be working with the GSMA to improve the security and privacy and all the carriers seem to just use Google’s software to run the backend.

This! Google is beating the drum about RCS, but Google Voice, their own service, does NOT support RCS.

I have faith in Google.

They will surely create and shit-can a dozen texting apps in the next decade. One may even fit my purposes until it too is shit-canned.

Nobody has more experience in building text apps than Google.

Shh, don't mention Google Voice or they might remember it exists and kill it. I can't think of a Google service that's been more useful in my life, and hate to think what I'll have to do when they kill it.

How is that relevant? Text messages have historically (and technically) been separated from standalone chat applications, so it makes perfect sense that Google Chat is separate from Messages.

On the contrary, merging the two is a "bad guy" move since it causes vendor lock-in (case in point, Apple).

I hope RCS will never be widely adopted. It's bad technology, and despite what Google says, it's not carrier-based:

Google runs almost the entire show (since carriers can't be bothered to actually run RCS servers) and gets effectively all messages sent over it in plaintext, unless you happen to use Google's "Messages" app, which is the only one capable of end-to-end encrypting messages (using a centralized key sever run, you guessed it, by Google)!

Google Talk was honestly better than this on literally every metric, and additionally didn't tie everything to a phone number as an identifier.

I feel the same. I feel like I remember years ago, when RCS was first being implemented, Google said they would open the APIs so any texting app could use RCS. RCS is the reason I stopped using Textra and moved to Google Messages. Textra did say at one point they would integrate the RCS APIs when it was opened, but nothing has happened yet.

Just like how they let you install “web apps” by hiding it deep within a “share” menu.

Can’t tell me that’s done in good faith either.

Compliance with what? No regulatory body or law has forced Apple to do this (yet).

Before iMessage, they used the green bubbles for SMS. So unless Apple was planning a long con, they believed the green bubbles were fine for their customers for years, and switched to a new color (blue) when iMessage came about.

Would you not be reprimanded for white text on a cyan background?

That is the alternative on iMessage.

The bubble is not blue.

   Edit: to be fair the text is also not "white"
   The approximate (sRGB) color codes are:
   "green"     #39ff5a  (57,255,90)
   "white"     #fdfdfd (253,253,253)
   "grey"      #d8d8d8 (216,216,216)
   "blue grey" #aeb9cc (174,185,204)
   "blue"      #218aff (33,138,255)

All the contrasts are terrible, but clearly a marketing decision.

https://coolors.co/contrast-checker/fdfdfd-218aff

For your own messages that you wrote and sent, not anyone else’s, and the contrast lower down on the screen is fine, it’s only at the top of the screen when it’s doing the fade-to-indicate-you-can-scroll-for-more thing that it runs afoul of contrast minimums.

iOS supports increasing color contrast for anyone who wants it, and whining about iMessage bubble colors while ignoring that fact is doing the world a huge disservice.

I don't have a writeup, but RCS doesn't specify e2ee. Google has their own thing that doesn't work with other RCS clients (including Apple).

Its hard to avoid Google's marketing when the end-to-end implementation proprietary to their RCS app. This is their technical paper which confirms that it is end-to-end encrypted using the Signal protocol. The actual RCS spec has no support for E2E at this point.

https://www.gstatic.com/messages/papers/messages_e2ee.pdf

Apparently Google acquired Jibe and offers it as a cloud solution to carrier OEMs to implement RCS.

https://www.gsma.com/get-involved/gsma-membership/gsma_orgs/...

https://techcrunch.com/2015/09/30/google-acquires-jibe-mobil...

https://android.googleblog.com/2015/09/committing-to-rcs-lat...

https://jibe.google.com/jibe-platform/

https://www.sicurezzaegiustizia.com/wp-content/uploads/2020/...

> RCS uses a set of standard internet protocols like Session Initiation Protocol (SIP)[1] to establish a connection between two clients through a central messaging server. This connection is then used to exchange the messages using Message Session Relay Protocol (MSRP)[2]. In some RCS deployments this server is hosted by the carrier, and in other deployments the server is hosted by Jibe Mobile from Google.

> In situations where the two clients are not on the same carrier network, they’re connected through multiple servers—one from each carrier. The connection between the RCS client app and the carrier’s messaging server is encrypted using Transport Layer Security (TLS). Server to server communications are also encrypted.

How end-to-end encryption in Google Messages provides more security

https://support.google.com/messages/answer/10262381

Google Messages end-to-end encryption technical paper

https://www.gstatic.com/messages/papers/messages_e2ee.pdf

Data security for RCS Business Messaging (RBM)

https://developers.google.com/business-communications/rcs-bu...

Even if Apple cracks and ports iMessage to Android, I would still expect them to use a green bubble. It's a social signal to shame those in the outgroup

why wouldn't they be? It's not iMessage. Won't support all iMessage functions.

Well it’s still not E2EE so it should he green in my opinion. Green means “this is being logged by the phone company like it’s 1999 and can be subpoenaed at any time”.

Sounds like that still true of RCS since it still works with the phone company. Why in the hell are they needed when every modern messaging app just worked using, you know, The Internet?

It does on my android phone, so it doesn'ct seem to be a limitation of the protocol.

It will. Unlike e.g. MMS or VoLTE, RCS (at least as recently implemented on Android) has never used special APNs or other network-only infrastructure.

Even when you have signal and mobile data, it'll take the same route as iMessage or WhatsApp, i.e. your regular "Internet" APN.

Cell phone carriers can set up their own RCS servers. All the major US carriers (AT&T, Verizon, T-Mobile US) outsourced their RCS to Google's Jibe platform, though.

Messaging apps haven't been pure SMS for a long time. If you've sent photos/images, it's using MMS, which basically uploads the picture to a HTTP server hosted by your carrier and sends the URL in a SMS message that the receiving app knows to automatically download and display the image, provided you have a data connection.

iMessage is proprietary to Apple, so of course it goes through Apple's servers. When you set up your iPhone, it registers your phone number with Apple's iMessage server so that whenever someone tries to send a message to your number, it sends it to the iMessage cloud instead of SMS. This can actually cause problems when you switch from an iPhone to Android because other Apple users trying to send you text messages might still get routed to iMessage instead of SMS, and there's no iMessage available for Android. You may have to use a website that Apple provides to manually deregister the phone number from iMessage in that case.

I'm not all that familiar with how RCS works but presumably there's a similar registration process so that other phones know that your phone is RCS capable, except decentralized since it's not controlled by a single company.

Both work via the public Internet, i.e. not a special APN, like MMS does; they use your regular data APN and accordingly also incur data charges. When you're on Wi-Fi, they use that.

As for who runs the servers: iMessage goes through Apple's servers.

RCS ostensibly goes through a federated network of telco-operated servers. But since almost none can actually be bothered to implement it (they've given up on trying to monetize it, so they have no incentive at all for incurring additional cost deploying and maintaining them), Google runs it for them, via a company they acquired [1].

> Also, if I'm in the SMS messaging app, I expect my messages to be SMS, not internet-based?

Is your SMS app actually called "SMS", these days? I usually see it called "messaging" or similar. In any case, assuming these apps do RCS, it'll be Internet-based.

[1] https://jibe.google.com/

It does

> Right now, when people on iOS and Android message each other, the service falls back to SMS — photos and videos are sent at a lower quality, messages are shortened, and importantly, conversations are not end-to-end encrypted like they are in iMessage.

Because RCS doesn’t have end to end encryption. Google has a proprietary service which is restricted to their own client, but no other RCS client can use it.

I think it's a shame too, but I blame Google at least as much as Apple for pushing this ridiculous standard in the first place.

As if there was any need to increase the lock-in to phone numbers and mobile carriers for communication and identification any more...

That won't happen unless they are forced. They know people buy iPhones to get the blue bubbles in iMessage, so they can be seen as "cool". They only make money by selling iPhones, not iMessage.

> The EU forcing Apple to adopt a cleartext protocol like RCS is deeply suspicious. Interoperability will force disclosure of message contents to the state and carrier.

I don't think it's suspicious. Almost nobody uses SMS in Europe anyway so this change is almost meaningless over here. It's just WhatsApp and then a little bit of Telegram, Signal etc on top.

I'm honestly not sure why anyone drives this (in Europe). I used to work for a mobile operator and RCS was a big thing around 2006-2009 in our R&D department. Then I changed to others jobs and almost didn't believe my eyes when it resurfaced with Google over a decade later. I was absolutely sure it was a dead horse already in 2009.

The EU is doing no such thing.

iMessage was explicitly determined to be out of scope of the DMA [1], simply because there isn't a meaninful user base in Europe (as is the case in almost the entire world except for the US).

[1] https://www.theverge.com/2024/2/13/23990679/apple-imessage-e...

Why would you suggest a conspiracy theory like that?

I'm not even sure what RCS is, other than a replacement text service that American phone companies offer. I am not aware that it's something that I could use over here.

That depends on how apple decides to implement it. They are a huge player, and I am sure they can make some kind of agreement with google so that they can message through the jibe servers which use the signal protocol.

All signs point to this being a response to Chinese regulation, not the EU.

https://daringfireball.net/2024/02/eu_rcs_imessage

I’d be more concerned if RCS was replacing an encrypted protocol. Going from SMS to unencrypted RCS is still an improvement, and it’s hard to imagine it being less secure than SMS already is. And at least with RCS they have the possibility of implementing encryption in the future, which they don’t with SMS.

> Use encrypted messaging protocols — iMessage, signal, WhatsApp…

Using RCS E2EE is trivial. The way google does it is to simply pack signal protocol messages in the RCS message payload. It works great and it's simple.

Key identities are managed with a central identity server (like signal does) of course but that's because it's only supported on Google's jibe platform.

This can be trivially resolved by having each carrier who supports E2EE to host a key identity server so that you can lookup keys by phone number (which RCS already uses to point you to the right federated carrier service).

All that's missing from RCS having E2EE by default is google having literally anyone else adopt RCS forcing them to properly federate E2EE.

Open/Interoperable FaceTime, Announced by Steve Jobs on June 7, 2010. Never Forget