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

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

MacFamilyTree 8.2.1 - Create and explore...
MacFamilyTree gives genealogy a facelift: modern, interactive, convenient and fast. Explore your family tree and your family history in a way generations of chroniclers before you would have loved.... Read more
LaunchBar 6.9 - Powerful file/URL/email...
LaunchBar is an award-winning productivity utility that offers an amazingly intuitive and efficient way to search and access any kind of information stored on your computer or on the Web. It provides... Read more
LaunchBar 6.9 - Powerful file/URL/email...
LaunchBar is an award-winning productivity utility that offers an amazingly intuitive and efficient way to search and access any kind of information stored on your computer or on the Web. It provides... Read more
MacFamilyTree 8.2.1 - Create and explore...
MacFamilyTree gives genealogy a facelift: modern, interactive, convenient and fast. Explore your family tree and your family history in a way generations of chroniclers before you would have loved.... Read more
Spotify 1.0.57.474. - Stream music, crea...
Spotify is a streaming music service that gives you on-demand access to millions of songs. Whether you like driving rock, silky R&B, or grandiose classical music, Spotify's massive catalogue puts... Read more
VOX 2.8.26 - Music player that supports...
VOX just sounds better! The beauty is in its simplicity, yet behind the minimal exterior lies a powerful music player with a ton of features and support for all audio formats you should ever need.... Read more
beaTunes 5.0.1 - Organize your music col...
beaTunes is a full-featured music player and organizational tool for music collections. How well organized is your music library? Are your artists always spelled the same way? Any R.E.M. vs REM?... Read more
LibreOffice 5.3.4.2 - Free, open-source...
LibreOffice is an office suite (word processor, spreadsheet, presentations, drawing tool) compatible with other major office suites. The Document Foundation is coordinating development and... Read more
Sparkle Pro 2.2 - $79.99
Sparkle Pro will change your mind if you thought building websites wasn't for you. Sparkle is the intuitive site builder that lets you create sites for your online portfolio, team or band pages, or... Read more
calibre 3.1.1 - Complete e-book library...
Calibre is a complete e-book library manager. Organize your collection, convert your books to multiple formats, and sync with all of your devices. Let Calibre be your multi-tasking digital librarian... Read more

Latest Forum Discussions

See All

This War of Mine gets a new ending and m...
This War of Mine just got a big new update, featuring free DLC that adds a new ending to the game, among other exciting changes. The update is celebrating the game's two-year release anniversary. Apart from the new ending, which will be quite... | Read more »
Summon eight new heroes in Fire Emblem H...
Nintendo keeps coming at us with Fire Emblem Heroes updates, and it doesn't look like that trend is stopping anytime soon. The folks behind the game have just announced the new War of the Clerics Voting Gauntlet, expected to start next Tuesday. [... | Read more »
The best deals on the App Store this wee...
iOS publishers are pulling out all the stops this week -- there's a huge number of seriously great games at discounted prices this week. Let's not waste any time and get right down to business. [Read more] | Read more »
The House of da Vinci (Games)
The House of da Vinci 1.0.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0.0 (iTunes) Description: Enter The House of Da Vinci, a new must-try 3D puzzle adventure game. Solve mechanical puzzles, discover hidden... | Read more »
Solve the disappearance of history’s gre...
Blue Brain Games invites you to indulge in an immersive hands-on 3D puzzle adventure in similar vein to The Room series, with its debut release The House of Da Vinci. Set during the historic period of the Italian Renaissance (when Leonardo himself... | Read more »
Age of Rivals (Games)
Age of Rivals 3.3 Device: iOS Universal Category: Games Price: $.99, Version: 3.3 (iTunes) Description: Deep civilization-building strategy in a fast-paced card game! | Read more »
Panthera Frontier (Games)
Panthera Frontier 1.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0 (iTunes) Description: | Read more »
Angry Birds Evolution beginner's gu...
Angry Birds changes things up a fair bit in its latest iteration, Angry Birds Evolution. The familiar sling-shot physics mechanics are still there, but the game now features team-based gameplay, RPG elements, and a new top-down view. With all of... | Read more »
Sega Forever is for the retro game fans
Sega is launching a new retro games service titled Sega Forever, in a move that's sure to delight games enthusiasts with a bit of nostalgia. Sega's releasing five classic games for free. The titles include Sonic the Hedgehog, Phantasy Star II,... | Read more »
The Little Acre (Games)
The Little Acre 1.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0 (iTunes) Description: | Read more »

Price Scanner via MacPrices.net

ABBYY TextGrabber 6 for iOS Implements Instan...
ABBYY has announced the release of TextGrabber 6.0.0, an important feature update to the company’s productivity app developed for iOS and Android devices. TextGrabber 6.0 now offers Real-Time... Read more
vPhone, First Smartphone That Can’t Be Lost,...
Austin, Texas based Hypori has introduced the vPhone, a virtual smartphone that affords every business user the benefits of separate work and personal phones, conveniently delivered on a single... Read more
Save this weekend with 2016 refurbished MacBo...
Apple has dropped prices on Certified Refurbished 2016 15″ and 13″ MacBook Pros by as much as $590 off original MSRP. An Apple one-year warranty is included with each model, and shipping is free: -... Read more
New 27-inch 3.4GHz iMac on sale for $1699, sa...
MacMall has the new 2017 27″ 3.4GHz iMac (MNE92LL/A) in stock and on sale for $1699 including free shipping. Their price is $100 off MSRP. Read more
Clearance 2016 MacBook Pros available for up...
B&H Photo has clearance 2016 13″ and 15″ MacBook Pros in stock today and on sale for up to $400 off original MSRP. Shipping is free, and B&H charges NY & NJ sales tax only: - 15″ 2.7GHz... Read more
Apple Ranks 9th In comScore Top 50 U.S. Digit...
comScore, Inc. has released its monthly ranking of U.S. online activity at the top digital media properties for May 2017 based on data from comScore Media Metrix Multi-Platform. * Entity has... Read more
10.5-inch iPad Pros available for up to $20 o...
B&H Photo has the new 2017 10.5″ iPad Pros available for up to $20 off MSRP including free shipping plus NY & NJ sales tax only: - 64GB iPad Pro WiFi: $649 - 256GB iPad Pro WiFi: $749 - 512GB... Read more
Three Off-The-Beaten-Track iOS Apps That Dese...
One of the great things about using iPads and iPhones is the vast selection of apps available for most anything you want or need to do. The three outlined in this article have been in my core app... Read more
Apple No. 1 Spot In Gartner Top 100 Vendors i...
Gartner, Inc. has unveiled the top global 100 vendors in IT in 2016 based on their revenue across IT (excluding communication services) and component market segments. In the Gartner Global Top 100:... Read more
Clearance iMacs available for up to $300 off...
B&H Photo has clearance 21″ and 27″ Apple iMacs available starting at $949, each including free shipping plus NY & NJ sales tax only: - 27″ 3.3GHz iMac 5K: $1999 $300 off original MSRP - 27″... Read more

Jobs Board

*Apple* News Product Marketing Mgr., Publish...
…organizational consensus on strategy and vision for publisher tools, authoring, and Apple News Format.Carries this strategy and vision across the organization to Read more
*Apple* Retail - Multiple Positions - Apple,...
Job Description: Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
Security Data Analyst - *Apple* Information...
…data sources need to be collected to allow Information Security to better protect Apple employees and customers from a wide range of threats.Act as the subject matter Read more
Lead *Apple* Solutions Consultant - Apple I...
…integrity, and trust.Success Metrics/Key Performance Indicators:Quantitative* Year over Year growth in Apple Product and Beyond the Box sales in the assigned Point of Read more
*Apple* Solutions Consultant till v%u00E5r...
…ethics, integrity, and trust.Success Metrics/Key Performance Indicators:QuantitativeYear over Year growth in Apple Product and Beyond the Box sales in the assigned Point Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.