Deloitte CIS Case Study

Printable Version   (PDF, 454.3KB)
Deloitte CIS

Enterprise Migration to Microsoft Unified Communications using AudioCodes Media Gateways


About Deloitte

Deloitte is the brand under which tens of thousands of dedicated professionals in independent firms throughout the world collaborate to provide audit, consulting, financial advisory, risk management and tax services to selected clients. These firms are members of Deloitte Touche Tohmatsu, a Swiss Verein (DTT). Each member firm provides services in a particular geographic area and is subject to the laws and professional regulations of the country or countries in which it operates. DTT helps coordinate the activities of the member firms but does not itself provide services to clients. DTT and the member firms are separate and distinct legal entities, which cannot obligate the other entities. DTT and each DTT member firm are only liable for their own acts or omissions, and not those of each other. Each DTT member firm is structured differently in accordance with national laws, regulations, customary practice and other factors, and may secure the provision of professional services in their territories through subsidiaries, affiliates and/or other entities.

About Deloitte CIS

Deloitte CIS is one of Russia’s leading professional services firms, providing audit, tax, consulting, and financial advisory services through nearly 3,000 people in 14 offices across nine countries in the region. Known as an employer of choice for innovative human resources programs, it is dedicated to helping its clients and its people excel.


With offices in nine countries, Deloitte CIS depends greatly on its communications infrastructure. Like other Deloitte member firms worldwide, Deloitte CIS had been using multiple systems for different types of communications. For telephony and voicemail, Nortel Communications Server 1000M IP-PBX, Nortel Call Pilot and Meridian Mail messaging systems were used, whereas Microsoft Exchange 2003 and Microsoft Live Communications Server 2005 solutions were used for email, instant messaging and presence services.

Deloitte is an IT-savvy company. Auditors and consultants make up the majority of Deloitte’s people and, as professional services providers, they are highly mobile and spend a great deal of time working outside of the office. Thus, they need all IT communications services to be available on their laptops wherever they are working at any given time – the office, a hotel, at home, or at a client’s office. As a result, 70% of Deloitte CIS people began using Nortel software telephones in 2004.

Over the years, all communications solutions have evolved independently, resulting in a low level of integration between these systems since they were treated as disparate communications silos. This arrangement was very inefficient for the business both from the end users’ and the IT department’s perspective. End users had to use different software clients that were not integrated at all, as well as remember multiple user names and PINs, and IT had to support redundant communications systems. Other Deloitte member firms in other countries faced the same situation and began investigating the possibility of integrating their telephony and IT infrastructure into a single communications network to break the silos, thereby reducing operational expenses and increasing productivity.


When Microsoft announced their Unified Communications strategy and came out with the first versions of Exchange Server 2007 Unified Messaging and Office Communications Server 2007 R1, it was only natural for Deloitte to deploy it in the CIS and around the world in order to enjoy the benefits of Unified Communications.

At that point, Deloitte CIS was already using AudioCodes MediaPack 1xx analog media gateways as fax adaptors at remote locations for their IP-PBX system. The firm had four MediaPack 118 and two MediaPack 124 units distributed in its branches, supporting the connection of dozens of fax machines to their system.

“Upon implementing Microsoft Exchange Server 2007 Unified Messaging, we had to select a qualified Media Gateway to connect the Exchange Server to Nortel PBX,” commented Denis Chernyadiev, IT Infrastructure Manager at Deloitte CIS. “As we were very happy with the quality of the AudioCodes media gateways we had been using for several years, it was only natural for us to use it to connect to the Exchange Server as well. We also got very positive feedback from our colleagues in other Deloitte member firms who had made the same decision.”

After the successful connection of Microsoft Exchange Server 2007 to Nortel IP-PBX with the AudioCodes gateway, Deloitte explored the possibility of connecting Nortel IP-PBX to Microsoft Office Communications Server R1 in order to allow integrated telephony support and direct communications between Nortel PBX users and Office Communications Server telephony users.

 “Although supporting direct integration between Nortel Communications Server 1000 and Microsoft Office Communications Server 2007 was theoretically possible, we had to invest a lot of time and energy in the Nortel PBX upgrade to make this happen. The upgrade was very expensive and contradicted our communications strategy, so after a pilot phase, we chose to use the AudioCodes gateways for this as well. This way, we were able to connect the two systems without having to change any configurations in our Nortel PBX. This also supported our long-term “communication silos break” strategy to switch our communication system over to Microsoft completely, and retire Nortel IP-PBX,” said Denis Chernyadiev.

Deloitte CIS currently uses two redundant Mediant 2000 gateways for connecting its Exchange Server 2007 and Office Communications Server 2007 R2 to Nortel IP-PBX and PSTN. The AudioCodes Mediant 2000 gateways connect to Nortel IP-PBX and PSTN, allowing full redundancy in the event of a failure.


“We have chosen to retire Nortel IP-PBXs in all of our branch offices and move to a communications system based on Microsoft and AudioCodes only. We feel very comfortable with the Microsoft and AudioCodes solution as it is standards based and very easy to manage. In fact, we completed the system integration ourselves, with some expert consultancy from AudioCodes people in Russia. We also plan to move to a centralized architecture and retire the PBXs in our remote branches once Microsoft communications Server 14 is released, using AudioCodes’ Survivable Branch Appliances,” said Denis Chernyadiev.