TweetFollow Us on Twitter

Jun 01 MacTech Online

Volume Number: 17 (2001)
Issue Number: 06
Column Tag: MacTech Online

Jabber

by Jeff Clites online@mactech.com

Last month we began our coverage of P2P (peer-to-peer) technologies. The P2P field is being fueled by open-source projects which have sprung up in response to the popularity of specific proprietary applications in this genre, by generalizing, improving, or simply imitating them. Last month we discussed Gnutella, an open-source protocol for peer-to-peer sharing of files and other resources. Gnutella was inspired by Napster, generalizing the concept to support sharing of things other than music files, and decentralizing searches to avoid any one critical point which could be attacked, by either technological or legal means. This month we are going to look into Jabber, which takes its cue from instant messaging (IM) and chat products such as AIM (AOL Instant Messenger), Yahoo Pager, MSN Messenger, ICQ, and IRC. Jabber's goal is to provide a "universal" XML-based platform for instant messaging, which can bridge to other protocols as well as support new applications of messaging.

Jabber originated with Jeremie Miller's frustration with having to use multiple pieces of IM software in order to keep up with all of his friends, who were using a variety of different IM systems. His response to this proliferation was to come up with a protocol which was designed to both serve as a messaging platform on its own and to transparently bridge to others, so that he could use one protocol (and one client application) to communicate with all of his friends. Unsurprisingly, he chose XML as the basis for Jabber. So what is Jabber, exactly?

Jabber in a Nutshell

Jabber isn't a specific application, and the Jabber community likes to point out that it isn't a protocol either—they prefer to call it a platform. In truth, Jabber represents a collection of XML-based message formats, and the protocol for communicating them.

Jabber is completely XML-based, and communicates over client-server based TCP/IP connections, modeled on the email system. Users are identified by Jabber IDs, which resemble email addresses, and are of the form user@server/resource. (The "resource" portion allows the same user to connect multiple times from different applications or locations, and so the name of the client application or location, such as "home" or "laptop", is often used.) Jabber users begin a session by connecting to their local Jabber server. Messages are sent by addressing them to other Jabber IDs and handing them off to the local server, which routes them to the remote user's server in a manner similar to how email is routed and delivered. The remote user then receives the message via a connection to his local server.

Jabber's design philosophy takes XML seriously, and also sees as fundamental the placing of the bulk of the logic on the server. As mentioned above, one of Jabber's original goals was to bridge to other IM system, so that Jabber users could talk to other IM users without either really having to care or fully realize that they are using different systems. The technology which allows this accordingly lives on the server side, and Jabber users bridge to other IM systems by having the server act as their proxy—from the point of view of the foreign IM system, the server is the AIM client (for example), and it takes care of translating Jabber messages into AIM messages, and vice versa. This translation is done by components of the server called "transports" (or more recently, just "components"). The value of this approach is that it makes the creation of Jabber clients relatively simple, and additional functionality can be added by upgrading Jabber servers, without requiring a widespread client upgrade.

But Jabber doesn't just bridge to other systems—in the ideal situation, everyone could just use Jabber natively. As an IM technology in its own right, Jabber is full-featured: it supports "buddy lists" as well as notification of whether these users are currently online. It goes a step further than most other IM systems, in that buddy lists (called "rosters") are stored server-side, which facilitates notification of online status (called "presence"), as well as allowing users to connect to Jabber server from different machines using different client software without having to keep separate rosters in sync. Additionally, notification under Jabber occurs only with consent—a user must "subscribe" to another user in order to receive notification of whether they are online, and the other user has to authorize the subscription. This affords additional privacy, and could be used to combat spammers (by refusing messages from users to which one is not already subscribed, for instance). Also, Jabber supports the concept of traditional IM messages (which Jabber calls "chat"), group chats similar to IRC (called "group chat"), and more passive messages.

Strengths and Weaknesses

In additional to serving as a traditional human-to-human communication technology, Jabber is aspiring to serve as a mechanism for facilitating application-to-application (A2A) communication, or as a middleware to transport other types of messages. Fanciful potential applications include "smart" appliances which communicate in order to negotiate for resources (such as a coffee pot which turns itself on when the alarm clock goes off). As of yet, there don't seem to be any applications in this arena, and it isn't clear if this is a reasonable goal—other technologies such as Java's Jini have not seemed to take off in the "smart appliance" area, and for more traditional application-to-application communication there is already a great deal of underutilized technology out there, and the idea of an AI-like communication between desktop applications isn't realistically on the horizon. As a transport mechanism for other forms of inter-process communication there is potential, but Jabber doesn't have a clear advantage over the alternatives already available, and for some applications a protocol more directly designed for this task might work better.

In general, Jabber seems to suffer a little from what I would call the "premature need for generalization", and this is just one of the symptoms. Although Jabber is trying to be general-purpose, it's clear that it was designed with instant messaging in mind—for instance, its message types are "chat", "groupchat", "default", and "error". In truth, many of the new XML-based protocols today are trying to fill some perceived general need at the same time they are trying to fill a specific one. In general, I'd prefer to see a strong solution to a particular problem (such as the need for an open instant messaging protocol), and have generalization come later, if it's really needed and after some experience has been gained with the concrete application. Then, the original use could become one application of a more general technology, possibly after reimplementation.

Jabber is composed of open protocols and formats, and there are open-source implementations of clients and servers as well. The importance of this shouldn't be underestimated, in light of the proliferation of mutually incompatible, restrictive IM technologies. But the most valuable and immediately useful aspects of Jabber, in my opinion, aren't really the direct consequence of the "open source" approach: they are actually security-related. First, it's straightforward for companies to set up a private Jabber server behind the corporate firewall. This is actually more significant than it may sound, because despite the inherent insecurity of using AIM (for instance) for communication of confidential material, it's so useful that people often do it anyway. With Jabber, all of this communication can happen without the need for it to pass through an external server, whose security isn't under the control of its users. In the same vein, Jabber is incorporating support for encryption, both PGP-like procedures for the encryption of message content, and SSL for encryption of client-server and server-server communication. They do get points off, however, for not incorporating this from the start; we have enough insecure protocols which originated while the internet was a safe, private playground, and anyone developing new protocols today has no excuse for ignoring the need for some level of encryption as a fundamental component.

Jabber Resources

If you're interested in Jabber from a developer's perspective (or as a user, for that matter), the central hub of all things Jabber is Jabber.org. Here you can find developer documentation, as well as FAQs, user guides, and links to client implementations. Developers will want to look at the Technology Overview, the Protocol Overview, and the Programmers Guide, as well as the links to available code libraries. Also, those implementing Jabber clients in particular will want to check out The Jabber Client Developer's Cheat Sheet, which will help steer you around the "gotchas". For examples of some alternative uses of Jabber, take a look at DJ Adams' articles on the O'Reilly Network, or on his own Fun with Jabber site. Adams' applications use the Net::Jabber Perl module, which makes this sort of experimentation a snap, and you'll want to get your hands on this if you are Perl-savvy. He also has an experimental implementation of doing XML-RPC over Jabber. O'Reilly has some additional general coverage of Jabber, both on their portal site and in their Peer-to-Peer book, the Jabber chapter of which is available online. Finally, try Eric Peyton's Fire IM client for Mac OS X, which supports Jabber as well as a variety of other IM protocols, and keep an eye on JabberCentral for coverage of current related news.

Jabber - Open Source XML-Based Interoperable Instant Messaging and Presence Platform
http://www.jabber.org/

Jabber FAQ
http://docs.jabber.org/general/html/faq.html

Jabber Technology Overview
http://docs.jabber.org/general/html/overview.html

Jabber Protocol Overview
http://docs.jabber.org/general/html/protocol.html

Jabber Programmer's Guide
http://docs.jabber.org/jpg/html/main.html

Jabber Projects - Jabber libraries
http://jabber.org/?oid=71

Jabber Client Developer's Cheat Sheet
http://homepage.mac.com/jens/Jabber/JabberClientCheatSheet.html

You Have Mail! [Mar. 09, 2001]
http://www.openp2p.com/pub/a/p2p/2001/03/09/adams_1.html

A More Sensitive Mail Notifier [Apr. 13, 2001]
http://www.openp2p.com/pub/a/p2p/2001/04/13/jabber.html

Fun With Jabber
http://www.pipetree.com/jabber/

Net::Jabber
http://search.cpan.org/search?dist=Net-Jabber

XMLRPC over Jabber
http://www.pipetree.com/jabber/XMLRPC/

XML Messaging with Jabber [Oct. 06, 2000]
http://www.openp2p.com/pub/a/p2p/2000/10/06/jabber_xml.html

Jabber Works: Here's How [Oct. 06, 2000]
http://www.openp2p.com/pub/a/p2p/2000/10/06/jabber_works.html

Peer-to-Peer: Chapter 6: Jabber
http://www.oreilly.com/catalog/peertopeer/chapter/ch06.html

epicware: Fire
http://www.epicware.com/fire.html

JabberCentral
http://www.jabbercentral.com

 
AAPL
$97.67
Apple Inc.
+1.41
MSFT
$43.63
Microsoft Corpora
+0.89
GOOG
$511.17
Google Inc.
-13.34

MacTech Search:
Community Search:

Software Updates via MacUpdate

Coda 2.5 - One-window Web development su...
Coda is a powerful Web editor that puts everything in one place. An editor. Terminal. CSS. Files. With Coda 2, we went beyond expectations. With loads of new, much-requested features, a few... Read more
Arq 4.6.1 - Online backup to Google Driv...
Arq is super-easy online backup for the Mac. Back up to your own Google Drive storage (15GB free storage), your own Amazon Glacier ($.01/GB per month storage) or S3, or any SFTP server. Arq backs up... Read more
Airfoil 4.8.10 - Send audio from any app...
Airfoil allows you to send any audio to AirPort Express units, Apple TVs, and even other Macs and PCs, all in sync! It's your audio - everywhere. With Airfoil you can take audio from any... Read more
Apple iMovie 10.0.6 - Edit personal vide...
With an all-new design, Apple iMovie lets you enjoy your videos like never before. Browse your clips more easily, instantly share your favorite moments, and create beautiful HD movies and Hollywood-... Read more
OnyX 2.8.8 - Maintenance and optimizatio...
OnyX is a multifunctional utility for OS X. It allows you to verify the startup disk and the structure of its System files, to run miscellaneous tasks of system maintenance, to configure the hidden... Read more
Parallels Desktop 10.1 - Run Windows app...
Parallels Desktop is simply the world's bestselling, top-rated, and most trusted solution for running Windows applications on your Mac. With Parallels Desktop for Mac, you can seamlessly run both... Read more
Apple Keynote 6.5 - Apple's present...
Apple Keynote makes it simple to create and deliver beautiful presentations. Powerful tools and dazzling effects bring your ideas to life. You can work seamlessly between Mac and iOS devices. And... Read more
OmniPlan 2.3.7 - Robust project manageme...
With OmniPlan, you can create logical, manageable project plans with Gantt charts, schedules, summaries, milestones, and critical paths. Break down the tasks needed to make your project a success,... Read more
Flavours 1.1.16 - Create and apply theme...
Flavours is a Mac application that allow users to create, apply and share beautifully designed themes. Classy Give your Mac a gorgeous new look by applying delicious themes! Easy Unleash your... Read more
Duplicate Annihilator 5.1.0 - Find and d...
Duplicate Annihilator takes on the time-consuming task of comparing the images in your iPhoto library using effective algorithms to make sure that no duplicate escapes. Duplicate Annihilator detects... Read more

Latest Forum Discussions

See All

My Very Hungry Caterpillar (Education)
My Very Hungry Caterpillar 1.0.0 Device: iOS Universal Category: Education Price: $3.99, Version: 1.0.0 (iTunes) Description: Care for your very own Very Hungry Caterpillar! My Very Hungry Caterpillar will captivate you as he crawls... | Read more »
Dungeon Dick (Games)
Dungeon Dick 1.1 Device: iOS Universal Category: Games Price: $.99, Version: 1.1 (iTunes) Description: Dungeon Dick is a fantasy adventure where you must discover the wicked plot to destroy the lands . 'Fling' at your foes and land... | Read more »
Here’s How the Apple Watch Could Transfo...
With the Apple Watch’s generic release date of, “early 2015” hovering on the horizon, it’s only a matter of time before gamers begin to ask “What’s in it for us?” The obvious choice would be to place entire games directly on the face of the watch,... | Read more »
Republique Episode 3: Ones & Zeroes...
Republique Episode 3: Ones & Zeroes is Available Now Posted by Rob Rich on October 17th, 2014 [ permalink ] Universal App - Designed for iPhone and iPad | Read more »
Loot Raiders Review
Loot Raiders Review By Campbell Bird on October 17th, 2014 Our Rating: :: PRESS BUTTON, GET LOOTUniversal App - Designed for iPhone and iPad This menu-based loot game is suitable to compel those with pretty extreme loot lust.   | Read more »
Angry Birds are Crashing Puzzle & Dr...
Angry Birds are Crashing Puzzle & Dragons Next Week Posted by Rob Rich on October 17th, 2014 [ permalink ] Next week, Puzzle & Dragons is getting a little angry. Because, you know, Angry Birds. It’s a… a pun. I thought… never mind. | Read more »
Incandescence Review
Incandescence Review By Andrew Fisher on October 17th, 2014 Our Rating: :: ALL TAPPED OUTUniversal App - Designed for iPhone and iPad Incandescence promises intense tapping action, but isn’t particularly fun.   | Read more »
Lion Pig (Games)
Lion Pig 1.0 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0 (iTunes) Description: "Leaving aside the biology of how a pig and a lion might meet, fall in love, and create this curious cross-breed, Lion Pig is a... | Read more »
Zero Lives (Games)
Zero Lives 1.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0 (iTunes) Description: Zero Lives is a puzzle game. Simple and elegant at its core but deep and captivating the more you play. Each puzzle will challenge... | Read more »
#SUPERHYPER (Games)
#SUPERHYPER 001 Device: iOS Universal Category: Games Price: $.99, Version: 001 (iTunes) Description: "This is a game that fans of challenging minimalist arcade games, not to mention pixel art, should keep an eye on" - Touch Arcade "... | Read more »

Price Scanner via MacPrices.net

Apple Pay Available to Millions of Visa Cardh...
Visa Inc. brings secure, convenient payments to iPad Air 2 and iPad mini 3as well as iPhone 6 and 6 Plus. Starting October 20th, eligible Visa cardholders in the U.S. will be able to use Apple Pay,... Read more
Textkraft Pocket – the missing TextEdit for i...
infovole GmbH has announced the release and immediate availability of Textkraft Pocket 1.0, a professional text editor and note taking app for Apple’s iPhone. In March 2014 rumors were all about... Read more
C Spire to offer iPad Air 2 and iPad mini 3,...
C Spire on Friday announced that it will offer iPad Air 2 and iPad mini 3, both with Wi-Fi + Cellular, on its 4G+ LTE network in the coming weeks. C Spire will offer the new iPads with a range of... Read more
Belkin Announces Full Line of Keyboards and C...
Belkin International has unveiled a new lineup of keyboard cases and accessories for Apple’s newest iPads, featuring three QODE keyboards and a collection of thin, lightweight folios for both the... Read more
Verizon offers new iPad Air 2 preorders for $...
Verizon Wireless is accepting preorders for the new iPad Air 2, cellular models, for $100 off MSRP with a 2-year service agreement: - 16GB iPad Air 2 WiFi + Cellular: $529.99 - 64GB iPad Air 2 WiFi... Read more
Price drops on refurbished Mac minis, now ava...
The Apple Store has dropped prices on Apple Certified Refurbished previous-generation Mac minis, with models now available starting at $419. Apple’s one-year warranty is included with each mini, and... Read more
Apple refurbished 2014 MacBook Airs available...
The Apple Store has Apple Certified Refurbished 2014 MacBook Airs available for up to $180 off the cost of new models. An Apple one-year warranty is included with each MacBook, and shipping is free.... Read more
Refurbished 2013 MacBook Pros available for u...
The Apple Store has Apple Certified Refurbished 13″ and 15″ MacBook Pros available starting at $929. Apple’s one-year warranty is standard, and shipping is free: - 13″ 2.5GHz MacBook Pros (4GB RAM/... Read more
WaterField Designs Unveils Outback iPad Slip...
Fresh on the heels of Apple’s announcement Thursday, WaterField Designs unveils its new Outback Slip Case for the iPad Air 2 and iPad mini 3 — a custom-fitted case for the just-announced Apple iPads... Read more
Apple Introduces iPad Air 2 & iPad mini 3...
Apple on Thursday introduced iPad Air 2, slimmed down again to just 6.1 mm, and weighing less than a pound. iPad Air 2 also features an improved Retina display claimed to deliver enhanced contrast... Read more

Jobs Board

Position Opening at *Apple* - Apple (United...
**Job Summary** At the Apple Store, you connect business professionals and entrepreneurs with the tools they need in order to put Apple solutions to work in their Read more
Position Opening at *Apple* - Apple (United...
**Job Summary** The Apple Store is a retail environment like no other - uniquely focused on delivering amazing customer experiences. As an Expert, you introduce people Read more
Position Opening at *Apple* - Apple (United...
**Job Summary** As businesses discover the power of Apple computers and mobile devices, it's your job - as a Solutions Engineer - to show them how to introduce these Read more
Position Opening at *Apple* - Apple (United...
…Summary** As a Specialist, you help create the energy and excitement around Apple products, providing the right solutions and getting products into customers' hands. You Read more
Project Manager, *Apple* Financial Services...
**Job Summary** Apple Financial Services (AFS) offers consumers, businesses and educational institutions ways to finance Apple purchases. We work with national and Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.