The Cisco-Microsoft battle for unified communications

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The Cold War between Microsoft and Cisco Systems for the much coveted "unified communications" market has escalated to an all-out war, with Microsoft Chairman Bill Gates predicting "the death of the [private branch exchange]."

Before I delve deeper, I have to come clean. My day job is as senior network engineer at a Cisco voice over IP (VoIP) partner. I have a vested interest in seeing the Cisco side of things dominate. But long ago I realized there is no use digging your head in the sand when something new comes along. Hence the hours I should have devoted to studying for my CCIE Voice lab exam have instead been spent attempting (mostly successfully) to understand, use and integrate the Microsoft IP telephony and VoIP applications to the best possible advantage.

Depending on who you talk to, unified communications is described as telephone and video collaboration, or as a converged network for voice and data, or used as an all-encompassing term to describe all forms of call and multimedia/cross-media message-management functions. For now, I'll use it to refer to any IP telephony product that can coexist with data.

Unless you have been living in a cave, you have to have noticed the buzz surrounding unified communications. In fact, Gartner identifies it as one of the "Top 10 Strategic Technologies for 2008." It is a competitive space currently filled by traditional PBX vendors (such as Avaya, Nortel, Alcatel and so on) and some would say dominated by Cisco, which long ago realized that IP telephony is more than just a way to help sell more POE switches.

Microsoft entered the market with much gusto with the release of Office Communication Server 2007 in October but, truth be told, the company has been dabbling in this space long before.

That Microsoft has experience with VoIP should come as no surprise. After all, the fundamentals of VoIP and IP telephony are simple: signaling protocols (such as the open standards SIP, H.323 and MGCP and the Cisco-proprietary SCCP) create and tear down calls between two like-protocol endpoints, while the actual voice is encoded inside a codec (such as G.711, G.729) and is then transported over an RTP stream (RTP being a simple extension to UDP).

Microsoft has employed aspects of the technology in a range of offerings. Microsoft's Xbox Live service, for example, uses voice to allow players to scream insults at enemy players or give orders to teammates while playing the hottest new Xbox title (such as Call of Duty 4). Microsoft Net Meeting, a rudimentary IP softphone, has been around for a long time, and before Office Communication Server there was Microsoft Live Communication Server 2005, a presence server that enabled Live Communication clients to see the status of other employees (for example, on the phone or in a meeting). Even the corporate staple, Microsoft Exchange 2007, has been getting in on the action, supporting "unified messaging," which translated basically means electronic, voice and fax "mail" all being accessible via a single interface.

Many of Microsoft's proposed IP telephony/VoIP products have only just come to market, so it is worth re-hashing the pieces that make up the Microsoft application and where they coexist with (or replace, depending on which side of the fence you sit) traditional PBX technologies.

The oft-hyped Office Communication Server is essentially the PBX destroyer. Equipped out of the box with "presence" (something you need to buy as a separate server from Cisco) and integrated with existing address books and corporate directories, OCS acts as the PBX of old. End users install an OCS client that allows them to see the presence of other users, instant message them and call them, if desired.

If your corporation has been sold on the benefits of collaboration (multiple people being able to edit the same document/spreadsheet/presentation at the same time) you will need to fork out for Microsoft Office Live Meeting, which integrates seamlessly with OCS.

Your voice-mail needs can then be taken care of with your existing Exchange 2007 server by simply configuring (and paying to enable) unified messaging.

In this battle, Microsoft fights on the land, in the sea and in the air. To get the equivalent functionality in Ciscoland, you would need four separate products (Cisco Call Manager, Presence, Unity and Meeting Place, respectively). When you factor in that you probably already have an Exchange server, it seems that your Microsoft VoIP defense budget leaves you room for other pressing domestic issues (virtualization perhaps?).

The Microsoft application, when all the pieces are integrated, is sexy. Taking a page from the Apple book, Microsoft has implemented the "gee-wiz" features that demo to customers very well. Be it the text-to-speech e-mail engine, the voice recognition Auto Attendant of Exchange Unified Messaging or the tight integration of Live Meeting with other Microsoft applications, the Microsoft products shout "hip" and "snazzy." (Two videos on the Microsoft Web site, based on the rather dreadful movie The Devil Wears Prada, showcase this perfectly.)

But for all the hype and jazz, the Microsoft application falls short on a number of issues that are going to be important to larger corporations. While taking care of the sex and sizzle, Microsoft has forgotten the fundamentals that make these technologies work. Basic features such as music-on-hold is slated for future releases, and even the venerable call-parking is not a feature currently supported. The core routing rules, such as which trunk to use when routing to emergency calls or how to use site access codes for overlapping extensions, are also very limited in flexibility on the Microsoft platform. Finally, the list of supported VoIP gateways is laughable, with none of the major vendors currently supported.

However, while these oversights might give Cisco and its partners some comfort, they are small and short lived when you consider the factors going Microsoft's way. Microsoft has a loyal troop base of MCSEs and other server experts chomping at the bit for a chance to roll out VoIP their way, with the software and the servers providing the intelligence and the network simply delivering the packets. No new Call Manager interfaces to learn, no separate directories to take care of, and familiar Microsoft products and jargon is nirvana to the Microsoft Administrator.

However, a lack of understanding of the importance of quality of service (QoS) in a converged network, and failure to understand the many finicky aspects of the Public Switched Telephone Network (PSTN), will doom many overzealous Microsoft administrators. A criticism often directed against Cisco VoIP engineers is their lack of understanding of the traditional PSTN and PBX technologies. With Microsoft administrators lacking understanding of the IP network as well the PSTN, this criticism will (pardon the pun) ring true.

The aftermath

The Microsoft IP telephony application is still in its infancy but already shows the telltale signs of a bright kid. If Microsoft is smart enough to send it to the right schools it will grow up to do great things. For the here-and-now, Cisco has little to fear from Microsoft in large corporations and the Microsoft reputation is a two-way street: While the company obviously has strong brand recognition, many large companies will be less than inclined to trust such a critical corporate function to a company with a less-than-enviable reputation for software quality.

The best bet at the moment is the use of both Microsoft and Cisco technologies. The use of Exchange 2007 for voice mail with a Call Manager is a no-brainer. Most companies currently run Exchange, and integrating Call Manager effectively is a snap. Smart channel partners that resell both Microsoft and Cisco will use this as an opportunity to push Exchange 2007 upgrades by touting the virtue of unified messaging when integrated with Call Manager.

The Cisco presence vs. Microsoft presence argument is going to come down to money: For Microsoft OCS clients to be able to "see" the on-hook/off-hook status of Cisco IP phones, they will need a Cisco Presence server. This means doubling-up on licensing and many companies may opt to use the Cisco Presence client. Finally, the Microsoft Live Meeting product is too tightly integrated into OCS at the moment to be a viable Cisco MeetingPlace alternative for current Call Manager users.

I have come to the conclusion that, as is usual in warfare, there is more gray than black and white. Both the Microsoft and Cisco products have their merits and downfalls.

For those in the trenches trying to sort all of this out, my advice is to become an expert in the technologies involved, rather than becoming a slave to any one vendor. For example, learn SIP forwards and backwards so you can debug your Ethereal packet captures to work out why OCS will not talk to Cisco Presence (I confess that I have poured over SIP output for a good four hours before finally sorting out all the integration gremlins). And learn why QoS is important, understand the different codecs available and their distinct advantages/disadvantages, but most of all, don't forget that until the PSTN dies, you are still going to need to integrate with it. A thorough understanding of ISDN, FXO, FXS and myriad of other considerations when connecting to the PSTN will serve you well.

Peter John Revill is the senior network engineer at a Perth, Australia-based Cisco VoIP partner. He has been working in computing for over seven years and specifically in the VoIP/IP telephony field for the past three. He holds a CCIE in Routing and Switching (#18371) and has his CCIE voice lab booked for March 2008. He can be contacted at The views in this article are Revill's and may not represent those of his employer.

This story, "The Cisco-Microsoft battle for unified communications" was originally published by Network World.

Copyright © 2008 IDG Communications, Inc.

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