In early April, in a drafty warehouse in Belmont, Calif., dozens of network engineers attempted to piece together hundreds of commercial and open source products as part of the 2008 Interop Labs initiative.
The Interop Labs serve as a neutral proving ground where vendors can test their products in accordance with emerging standards. The all-volunteer teams of network and software engineers have a long history of providing an honest assessment of how useful these technologies will or won’t be in a large scale network.
A focal point of this year’s iLabs endeavours involved one of the hottest buzzwords in the network industry: unified communications. Unified communications offers the potential for anywhere, anytime connectivity between employees and the enterprise.
But as the InteropLabs team found in piecing together more than a dozen commercial and open-source voice, data and messaging platforms, the technology is still at a relatively early stage, and today represents more promise than practice.
The team defined unified communications as the ability to be contacted using any method of your choosing. It’s understandable if that definition sounds a bit like the one for unified messaging, once considered the Holy Grail of messaging. With unified messaging, the key idea was that a single piece of client software or hardware could receive all messages for a given user.
An oft-cited example was having voice mail delivered to an e-mail in-box. Unified communications adds three new elements not present with unified messaging: presence, instant messaging and mobility.
Presence — the ability to signal availability and, perhaps, willingness to communicate — is arguably the most important of the many unified communications building blocks. The status messages in instant-messaging clients (available, busy, on the phone, out to lunch, and the like) are the best-known examples of presence information.
Instant messaging (IM), once viewed with skepticism by enterprise network managers, also has become a mainstay in enterprise networks. This capability comes by way of corporate messaging servers inside as well as through popular Internet-based services such as AOL Instant Messenger and Yahoo Messenger.
Mobility goes well beyond just delivering e-mail to BlackBerrys and other smartphones. Many phones and other portable devices today use GPS or other location-finding technologies that can help enterprises enhance business communications. For example, a fleet of mobile workers can be alerted to avoid traffic jams and IT staff can monitor server and network operations from an ever-expanding list of mobile devices.
The IETF has described two protocols — SIMPLE (Session Initiation Protocol for Instant Messaging and Presence Leveraging Extensions) and XMPP (Extensible Messaging and Presence Protocol) — to deal with presence, messaging and mobility. As the InteropLabs team discovered in building different systems, though, not all parts of either protocol are fully defined, and not all systems support both protocols.
PUTTING IT ALL TOGETHER
The InteropLabs team’s work seeks to demonstrate anytime, anywhere communications with a series of demos that tie together disparate messaging platforms. In all, the team identified eight demos to showcase unified communications:
• Alice and Bob are communicating by instant messenger, but decide they need to speak on the phone instead. Bob is on the road, reachable only by cell phone, while Alice is in her office. The unified communications system automatically figures out locations and phone number and places calls to Bob and Alice. Neither party needs to know anything about phone numbers or locations.
• Alice communicates with Bob, and a calendar automatically enters this event (a useful billing feature for lawyers, consultants, accountants and others who bill on a time and materials basis).
• Because Alice already has a meeting in her calendar, her phone won’t ring, but she will still be reachable through instant messaging.
• Alice steps away from her desk, and thus should only accept voice mail but not instant messages or videoconferences.
• Alice is in a meeting, and should be reached only by voice mail or e-mail (no voice or video).
• It’s after 5:30 p.m., so Bob should receive any communications intended for Alice.
• Whenever Bob teaches a course at a central location, video links automatically get set up at remote locations.
• When Alice dials 911 in an emergency, a company’s or university’s security team automatically gets notification both via instant message and e-mail.
All the pieces needed to put together each of these demos exist today. But as the team learned, getting them to work across multiple platforms and protocols — or in some cases, even within a single vendor’s solution — remains a pretty tall order. EASIER SAID THAN DONE Setup woes are par for the course with UC today and in the experiment, that was certainly evident.
It took longer than the time allotted during hotstage to get all the platforms up and running. The InteropLabs team of six veteran network engineers — all with extensive experience with SIP, SIMPLE, XMPP, and a wide variety of server and client platforms — encountered numerous setup issues, including:
• Multiple attempts to install Microsoft’s Office Communications Server (OCS). Beyond OCS, setup involves multiple other servers (Active Directory, SQL Server, Exchange, certificate authority and SharePoint), set up on the right combination of 32- and 64-bit server operating systems.
• Many hours of debugging to get the open source Postfix/Dovecot e-mail server to authenticate users against an external LDAP server.
• Limited support for presence information, even in open-source platforms. Not all of the demo’s open-source PBXs passed along presence information to attached clients.
• None of the major commercial PBX vendors had equipment at hotstage, so connecting proprietary messaging and presence protocols to the rest of the test bed was impossible.
Getting unified communications working today requires understanding of diverse platforms and protocols. Just as e-mail only became the Internet’s killer app after consensus formed around open protocols, the industry is only beginning to tap the power of open messaging standards.
