Standards Watch : Standardizing IM and Presence Technologies

Instant messaging and presence technologies (i.e. buddy lists that indicate users’ online status) have garnered more than 100 million users on AOL, Yahoo and MSN.

As push-to-talk, MMS and other messaging services are launched to increase revenue and reduce churn, standards are necessary to facilitate interoperability among service providers.

Widespread Adoption

Last year, session initiation protocol (SIP) emerged as a possibility for IM and presence technologies, as it was designed to operate over any type of IP network, whether wireless or wireline. SIP deployments in wireline IP networks have competed against legacy standards, such as H.323. Since its inception, the International Softswitch Consortium has chosen SIP as the signaling mechanism between softswitches in IP-based wireline carrier networks. “In those cases, SIP acts as the signaling ‘glue’ that enables softswitch-to-softswitch signaling, as well as softswitch-to-application server and application server-to-media server signaling,” says Jonathan Rosenberg, chief scientist at dynamicsoft and author of the SIP and SIMPLE standards.

SIP also garnered considerable support from Microsoft, which incorporated it into Windows XP to enable voice, presence and messaging capabilities. Microsoft also adopted SIP to provide real-time communications for its Windows Messenger and MSN Messenger clients.

In wireless, the 3GPP and 3GPP2 consortia chose SIP as the call control standard for 3G networks, and last month, the IETF’s SIP working groups also adopted SIP-related requirements for enhancing wireless networks by enabling messages to be compressed for more efficient transport over wireless air interfaces.

Vonage offers VoIP using SIP for consumer, residential and second service over DSL, and MCI is developing an enterprise offering around SIP presence technology.

Keep It SIMPLE

The IETF last month also approved SIP for Instant Messaging and Presence Leveraging Extensions (SIMPLE), an extension of SIP for accessing and managing presence data on networks. “SIMPLE will be a hot new piece of SIP,” says Rosenberg, noting that it defines mechanisms for subscribing to, and being notified of, a user’s state changes on a SIP network. “This mechanism will enable service providers to create a user status list similar to the AOL ‘buddy list’,” explains Rosenberg. By adding presence technology to voice mail, phone tag can be eliminated. “By depressing one key or another, the user can press a number to be prompted with information about the presence of the receiving party’s device—all in real-time,” he further explains. For more on presence-enabled services, see “Demystifying Presence-Based Services,” p. 50.

With SIMPLE, the vision is to enable subscribers to share any event with a set of authorized buddies. Devices will inform callers of whether the party being called is on the phone, if he or she is at work, and at what location, as well as the capabilities of the device (voice, text or video.) “These capabilities will bolster use of interactive turn-based games, enterprise applications, dispatch-based applications and advanced PBX-type functions,” says Rosenberg. “Geo-location applications, which demonstrate the physical locations of cellular users, will enable fleet tracking for trucking or limos, for example, or younger subscribers to know the locations of their buddies.”

“SIP and SIMPLE thus far have support from Microsoft, Sun Microsystems, [IBM’s] Lotus Software, Cisco, Nortel, dynamicsoft, and most of the bigger architectural and software companies,” Rosenberg says. “Growth is excellent, and we have more than 40 companies deploying SIP in one form or another, and we expect there to be more than 100 soon.”

Microsoft has embraced SIMPLE as the presence and IM framework for both its servers and its services. Similarly, AOL has committed to using SIMPLE as the interface for integrating with other instant messaging services.

Reuters information service has a large user base running SIP and SIMPLE using Microsoft technology. Microsoft also is in beta with customers using its Greenwich server, which is SIP- and SIMPLE-based.

Evolving Challenges

The next phase will be to enhance functionality to make systems richer through extensions that add authorization and privacy features for more robust devices. “For now, existing devices suffice for voice mail applications, as the presence information about availability can be extracted from the telephone network,” says Rosenberg. However, as more data is fed into applications, handsets will have to tell the network more information.