Comment on Why do I need a domain to access my Funkwhale library but not SyncThing?
NaibofTabr@infosec.pub 1 week ago
But if I’m reading the materials correctly, I’ll need to set up a domain and pay some upfront costs to make my library accessible outside my home.
Why is that?
So when your mobile device is on the public internet it can’t reach directly into your private home network. The IP addresses of the servers on your private network are not routable outside of it, so your mobile device can’t talk to them directly. From the perspective of the public internet, the only piece of your private network that is visible is your ISP gateway device.
When you try to reach your Syncthing service from the public internet, none of the routers know where your private Syncthing instance is or how to reach it. To solve this, the Syncthing developers provide discovery servers on the public internet which contain the directions for the Syncthing app on your device to find your Syncthing service on your private network (assuming you have registered your Syncthing server with the discovery service).
This is a whole level of network infrastructure that is just being done for you to make using Syncthing more convenient. It saves you from having to deal with the details of network routing across network boundaries.
Funkwhale does not provide an equivalent service. To reach your Funkwhale service on your private network from the public internet you have to solve the cross-boundary routing problem for yourself. The simplest and most reliable way to do this is to use the DNS infrastructure that already exists on the public internet, which means getting a domain name and linking it to your ISP gateway address.
If your ISP gateway had a static address you could skip this and configure whatever app accesses your Funkwhale service to always point to your ISP gateway address, but residential IP addresses are typically dynamic, so you can’t rely on it being the same long-term. Setting up DynamicDNS solves this problem by updating a DNS record any time your ISP gateway address changes.
There are several DynDNS providers listed at the bottom of that last article, some of which provide domain names. Some of them are free services (like afraid.org) but those typically have some strings attached (afraid.org requires you to log in regularly to confirm that your address is still active, otherwise it will be disabled).
Azzu@lemmy.dbzer0.com 1 week ago
Perfect explanation. This kind of thing shows why tech giants are giants and why selfhosted is a niche. People like paying for convenience.
NaibofTabr@infosec.pub 1 week ago
Thank you, I try. It’s always tricky to keep network infrastructure explanations concise and readable - the Internet is such a complicated mess.
Well, I would simplify that to people like convenience. Infrastructure of any type is basically someone else solving convenience problems for you. People don’t really like paying, but they will if it’s the most convenient option.
Syncthing is doing this for you for free, I assume mostly because the developers wanted the infrastructure to work that way and didn’t want it to be dependent on DNS, and decided to make it available to users at large. It’s very convenient, but it also obscures a lot of the technical side of network services which can make learning harder.
There’s also always the “why reinvent the wheel?” question, and consider that the guy who is selling wheels works on making wheels as a full-time occupation and has been doing so long enough to build a business on it, whereas you are a hobbyist. There are things that guy knows about wheelmaking that would take you ten years to learn, and he also has a properly equipped workshop for it - you have some YouTube videos, your garage and a handful of tools from Harbor Freight.
Sometimes there is good reason to do so (e.g. privacy from cloud service data gathering) but this is a real balancing act between cost (time and money, both up-front and long-term), risk (privacy exposure, data loss, failure tolerance), and convenience. If you’re going to do something yourself, you should have a specific answer to the question, and probably do a little cost-benefit checking.