WhatsApp is (or was) using XMPP for the chat part too, right?
When I was IT person on a research ship, WhatsApp was a nice easy one to get working with our "50+ people sharing two 256kbps uplinks" internet. Big part of that was being able to QoS prioritise the XMPP traffic which WhatsApp was a big part of.
Not having to come up with filters for HTTPS for IP ranges belonging to general-use CDNs that managed to hit the right blocks used by that app, was a definite boon. That, and the fact XMPP was nice and lightweight.
As far as I know google cloud messaging (GCN? GCM? firebase? Play notifications? Notifications by Google? Google Play Android Notifications Service?) also did/does use XMPP, so we often had the bizarre and infuriating very fast notifications _where sometimes the content was in the notification_ but when you clicked on it, other apps would fail to load it due to the congestion and latency and hardcoded timeouts TFA mentions.. argh.
But WhatsApp pretty much always worked, as long as the ship had an active WAN connection.... And that kept us all happy, because we could reach our families.
> WhatsApp is (or was) using XMPP for the chat part too, right?
It's not exactly XMPP, it started with XMPP, but XML is big, so it's tokenized (some details are published in the European Market Access documentation), and there's no need for interop with standard XMPP clients, so login sequence is I think way different.
But it runs on port 5222? by default (with fallbacks to port 443 and 80).
I think GCM or whatever it's called today is plain XMPP (including, optionally, on the server to server side), and runs on ports 5228-5230. Not sure what protocol apple push is, but they use port 5223 which is affiliated with xmpp over tls.
So I think using a non 443 port was helpful for your QoS? But being avaialable on port 443 is helpful for getting through blanket firewall rules. AOL used to run AIM on all the ports, which is even better at getting through firewalls.
I once got asked "what was a life changing company/product" and my answer was WhatsApp - to slightly bemused looks.
WhatsApp connected the world for free. Obviously they weren't the first to try but when my (very globally distributed family) picked up WhatsApp in '09/'10 we knew we were onto something different. Being able to stay in touch with my brother half way across the world in realtime was very special. Nothing else at the time really competed. SMS was expensive and had latency. Email felt clunky and oddly formal - email clients don't feel "chatty". MSN was crap on mobile and you both had to be online. Ditto for Skype. For calls we even used to do this odd VOIP bridge where you would each call an endpoint for cheap international phone calls.
Meanwhile in 2012, I was able to install WhatsApp on my mum's old Nokia Symbian feature phone, use WhatsApp on a pay-as-you-go sim plan in Singapore communicating over WAP. The data consumption was so low I basically survived 2 months on maybe 1-2 top ups. Compare that with the other day where I turned on roaming on my phone (so I could connect to Singtel to BUY a roaming package) and my phone passively fetched ~50+ MB in seconds and I was hit with 400SGD of data charges (I was able to get them refunded)
I am very grateful to all the work and thought WhatsApp put into building an affordable global resilient communication network and I hope every one of the people involved got the payout they deserve.
When I was IT person on a research ship, WhatsApp was a nice easy one to get working with our "50+ people sharing two 256kbps uplinks" internet. Big part of that was being able to QoS prioritise the XMPP traffic which WhatsApp was a big part of.
Not having to come up with filters for HTTPS for IP ranges belonging to general-use CDNs that managed to hit the right blocks used by that app, was a definite boon. That, and the fact XMPP was nice and lightweight.
As far as I know google cloud messaging (GCN? GCM? firebase? Play notifications? Notifications by Google? Google Play Android Notifications Service?) also did/does use XMPP, so we often had the bizarre and infuriating very fast notifications _where sometimes the content was in the notification_ but when you clicked on it, other apps would fail to load it due to the congestion and latency and hardcoded timeouts TFA mentions.. argh.
But WhatsApp pretty much always worked, as long as the ship had an active WAN connection.... And that kept us all happy, because we could reach our families.