ShoreTel, Inc., of Sunnyvale, California has been in the IP telephony business since 1996, and installed their first telephone system in 1998. The privately held company is backed by some impressive financial names, including JP Morgan and Lehman Brothers, and has an eight year track record of providing IP-based solutions. They have achieved a 90 percent growth rate—a feat that has outstripped much of their competition, including many of the larger players in this industry. As a company, one of their key objectives is providing exemplary customer satisfaction and service—unfortunately a lost art among many firms these days—which may explain their success.
The ShoreTel system is a completely distributed, scalable solution layered on the IP network that was designed with embedded reliability, and without single points of failure. It is targeted for a range of customer sizes, from small to large businesses, with a system that is scalable up to 10,000 ports. It is also adapted for an international customer base, with English, French, Spanish and German languages supported, and sales and support locations in North and South America, Europe, and Asia.
At the heart of the system is a call control architecture that distributes call management functions to intelligent gateways, which ShoreTel calls voice switches. These voice switches can be located anywhere on the IP network. Similarly, the ShoreTel architecture distributes voice applications, such as voicemail and automatic attendant functions, to servers across multiple locations, rather than centralizing applications at the network core. The resulting solution provides a single-image system for all locations and all voice applications.
A ShoreTel phone system typically consists of five key elements: ShoreGear Voice Switches, which provide a gateway to telephones and trunks as well call control software for the gateways and IP phones; ShoreWare Software for voice mail and automated attendant services; ShoreWare Personal Call Manager desktop productivity software; ShoreWare Director for system management including installation, administration, maintenance, and call detail reporting; and ShorePhone telephones.
Additional options depend upon a customer’s particular needs, and might consist of the ShoreWare Operator Call Manager for operators and executive assistants; ShoreTel Mobility solutions for a mobile workforce; ShoreTel Converged Conferencing for large audio conferences—as well as collaboration tools of application sharing, desktop sharing, instant messaging ,and presence; and the ShoreTel Contact Center solutions for informal, formal and advanced contact centers. All elements are designed to operate as a single PBX that serves the entire enterprise.
Five different models of ShortGear voice switches are available. The ShoreGear-120/24, ShoreGear-60/12, and ShoreGear-40/8 support up to 120, 60, and 40 IP telephones, or 24, 12, and 8 analog devices, respectively. The ShoreGear-T1 provides a high-density T1 interface for central office trunking applications, or connections to existing PBXs. The ShoreGear-E1 provides an E1 interface for European ISDN services using the Primary Rate Interface (PRI).
Reliability is one of the key attributes of all the ShoreTel switches. All of the voice switches use flash memory instead of a mechanical hard disk for program storage to increase system reliability. Similarly, call control is distributed between the various switches, so that if one switch were to fail, the other switches in the network can continue to operate. If a voice switch fails or is isolated by a network fault, the phones can automatically transfer to another switch to provide complete redundancy. Similarly, if a switch connected to the Public Switched Telephone Network (PSTN) fails, the systems automatically routes calls out an alternative switch. Backup attendant and power fail transfer capabilities are also included. The systems are compatible with the Session Initiation Protocol (SIP) and the Media Gateway Control Protocol (MGCP), and include support for a number of industry-standard codecs, including G.711 and G.729a.
Further details on the ShoreTel architecture and products can be found at www.shoretel.com. Our next tutorial will continue our examination of vendors’ architectures.
Copyright Acknowledgement: © 2006 DigiNet ® Corporation, All Rights Reserved
Mark A. Miller, P.E. is President of DigiNet ® Corporation, a Denver-based consulting engineering firm. He is the author of many books on networking technologies, including Voice over IP Technologies, and Internet Technologies Handbook, both published by John Wiley & Sons.