What Is XMPP and How Do You Use a Public Jabber Server Like Jabbim?

XMPP (Extensible Messaging and Presence Protocol), historically called Jabber, is an open instant messaging protocol. A public XMPP server such as Jabbim gives you a Jabber address and connects you to other XMPP users and networks. You use it by registering an account on the server, then signing in with any XMPP client — desktop or mobile. Jabbim states its services are free of charge, and it offers gateways to other networks plus its own local services.

What XMPP actually is

XMPP is a messaging protocol, not an app. The server handles your account and message routing; the client is the software you install. That separation is the main practical difference from closed messengers:

Open protocol — you choose your own client instead of being locked to one vendor's app.
Interoperability — Jabbim says its users can chat with users of other XMPP-enabled services and public Jabber servers, naming Google Talk, LiveJournal Talk, WP Spik, Gizmo Project, and Tipic IM among them.
Encryption — Jabbim states it uses encryption to protect your messages.
Mobility — the same account works from a desktop, a notebook, a PDA, or a mobile phone; Jabbim frames this as paying for transmitted data rather than SMS.

What a public server like Jabbim provides

Jabbim describes itself as an instant messaging service that lets you send messages to friends in almost real time. Beyond basic messaging, the site lists:

Transports and gateways to other networks: AIM, Yahoo!, Skype, ICQ, Twitter, Facebook, and a Telegram gateway.
Up to 1 GB of data storage.
Multi-user conference with live community support.
Local services for Czech, Polish, and Slovak users — train and bus timetables, dictionaries, SMS gateways, TV schedules.
A weather forecast and a status icon you can embed on your own website.
No ads, no spam, per the site's own description.

Jabbim also offers a VIP/sponsor program. The site links to pages explaining how to become a sponsor and what you get in return, and lists PayPal as a payment platform. Treat the free tier and the VIP tier as separate things: the general service is described as free, while VIP is a sponsorship arrangement with its own terms on those pages.

How to get started

Register an account. Jabbim's site has a registration entry point ("Register!"). You'll end up with a Jabber ID in the form [email protected], which is the address other people use to reach you.
Install an XMPP client. Jabbim's download section points to clients including Pidgin and Psi+ (Psi+ is recommended for the Tor setup described below). You can also use a web client from the site.
Sign in. Enter your full Jabber ID and password in the client. The client connects to the Jabbim server, and your contacts see you as online.
Add contacts and message. Add other Jabber IDs — on Jabbim or on any other XMPP server — and start chatting.
Set up gateways if you need them. In your client, use service discovery to find the gateway you want. For Telegram specifically, Jabbim's instructions are: in your client, use service discovery and register your phone number in international format at telegram.jabbim.com.

Expected result: after step 3 you have a working account and can exchange messages; after step 5 you can reach contacts on the bridged networks from the same client.

Connecting over Tor

Jabbim supports connection via Tor. The site gives this onion address and port:

mrbenqxl345o4u7yaln25ayzz5ut6ab3kteulzqusinjdx6oh7obdlad.onion:5222

After installing Tor, configure your client to use a Socks5 proxy at 127.0.0.1 with port 9050 (Tor client) or 9150 (Tor Browser), and use the hostname above. Psi+ is the recommended client for this.

Practical things to watch

Certificate validation. Jabbim's flash news notes that from 30 September 2021 some users may have had problems validating the server certificate, and advises updating client software (Pidgin, Psi+ are named). If you hit a certificate error, updating the client is the first thing to try.
Server status. The site maintains a server status page — worth checking if connections fail, since the problem may be on the server side rather than your client.
Account and terms. Registration and use are governed by the site's terms of use; read them before relying on the service for anything important.
Client choice matters. Because XMPP is open, features like service discovery, gateway registration, and proxy settings live in the client, not the server. If a step above doesn't match your client's menus, the client's own documentation is the place to look.

Who this suits

Jabbim fits you if you want a free public XMPP account, value choosing your own client, and need gateways to networks like ICQ, Telegram, or Facebook — or if you're in the Czech, Polish, or Slovak region and want the local timetable, dictionary, and SMS services. If you only need to message people who all use one closed app, a public XMPP server adds setup steps without an obvious payoff.