Avaya Intros SIP-Standardized IP Telephony

Transitioning to converged communications just got get easier last Monday, as Avaya introduced its new Session Initiation Protocol (SIP) portfolio. However, key features will need to be implemented before high-availability, enterprise-wide deployments can occur.

At the core of the announcement is Avaya's Converged Communications Server (CCS), a SIP proxy server that connects to the company's proprietary IP telephony solution, the Avaya Call Manager (ACM). The CCS will add SIP-based voice, presence, and Instant Messaging (IM) services. Avaya will also introduce the Avaya IP Softphone R5 with IM, a SIP-enabled softphone that integrates the three technologies, as well as a low-end SIP handset, the Avaya 4602 IP Telephone.

In many ways, Avaya's CCS highlights the future direction of established voice players -- namely, converged communications running on open systems. While IBM and Microsoft may dominate the general-purpose messaging and communications space, Avaya and other PBX suppliers are grappling with ways to deliver groupware capabilities to the telephony marketplace.

The CCS is a result of those efforts. It uses presence in uniquely voice-centric ways. When an Avaya softphone user is on a call, for example, the presence indicator will automatically indicate this state. Similarly, the IM client is tied directly to the softphone and runs over an encrypted Transport Layer Security (TLS) channel, which picks up on the top-notch security associated with the voice environment.

This functionality isn't just limited to IP users, either. With Avaya's SIP portfolio, customers can migrate to SIP while protecting their existing investment in Avaya hardware. The CCS hangs off the ACM, providing SIP addresses to proprietary Avaya clients running H.323, analog, or digital handsets. The CCS also inherits the ACM's extended functionality, providing call capabilities not found in SIP, such as call parking.On the client side, existing Avaya users gain converged functionality through Avaya's IP softphone. The softphone lets users control their desktop phone from a PC by pointing and clicking on a phone number in a Web browser. It also allows them to perform a variety of functions through Microsoft Outlook, such as dialing numbers, displaying Outlook contacts upon receiving an incoming call, and logging calls to Outlook's journal. IM is available in the softphone with the deployment of the CCS and a SIP license.

Today, the CCS is aimed at mid-sized deployments. Up to 3,500 endpoints can be run off a single CCS server, or 17,500 users under a five-server CCS cluster. Avaya couldn't verify whether those quoted numbers were for registered users only, or for active users as well.

Within the cluster, the CCS servers, called domain servers, communicate with the desktops and the ACM, as well as with one another. A separate server, the edge server, delivers requests from other applications or over the Internet to the cluster. "The trend over time, as I see it, is for businesses to buy IP telephony connectivity and have it come with their IP service," said Lawrence Byrd, a convergence strategist at Avaya.

Avaya isn't the only voice player with those views. The move to standalone SIP server architectures, also called decomposed server architectures, is being widely adopted by established PBX players. Avaya's chief competitor, Nortel Networks, introduced a SIP server last summer. Other PBX players will introduce similar architectures in the forthcoming weeks.

Ironically, as voice players adopt this decidedly data-centric approach, data vendors in the Voice over IP (VoIP) arena are going through their own changes. Cisco Systems, an early proponent of the decomposed server architecture and SIP, targets its SIP proxy server at the carrier network, not the enterprise. In addition, its Call Manager doesn't support SIP endpoints.Meanwhile, Pingtel, another early proponent of the architecture, has gone a step further and embraced a Linux-style model, giving away its proxy server code and then charging for service, support, and supplementary products, such as additional audio codecs.

In order for Avaya to compete, it will have to prove to existing customers that it's the best migration path toward converged communications, while at the same time drawing new customers to its functionality. That's going to require adding some key functions to its product set. Resiliency features, such as clients automatically rehoming to a new proxy server should the primary server fail, will be added later this year.

The product doesn't currently offer a built-in presence server. Presence updates are distributed directly between clients, creating significant network overhead. Avaya expects to introduce a presence server that will correct this problem in May.

The CCS runs on Linux on one of Avaya's ruggedized rackmount servers, such as the S8700, and requires an ACM. The complete hardware and software package runs $6,100, with a $25 per user license charge. The 4602 will list for $195, but street price is expected at around $100 to $120. The IP Softphone R5 runs at $130.