Making Your WAN a Fast Lane: One Company's Story

As associate director at Linklaters, David Bennett is responsible for the WAN and reports into the CIO as the head of (ISS) Information Systems and Strategy development. He shared a case study of the firm's recent WAN revamp with CIO.com

Linklaters is one of the largest law firms in the world, operating in more than 30 locations in 23 countries, advising companies, financial institutions, and governments. The firm's 540 equity partners and 2,000 lawyers cover 18 core practice areas, including capital markets, competition and antitrust, tax, mergers and acquisitions, intellectual property and technology.

Make Virtualization Work Better Across the WAN

As a global company with global clients, Linklaters' IT department was tasked with an enormous objective: to ensure that information can be accessed by our employees anywhere in the world with consistent performance and reliability. For security, cost and management reasons, all of our information is housed in four data centers, housed in Atlanta, Hong Kong and two locations in the UK.

Linklaters determined that a thin-client desktop architecture was the best way to minimize expenditures while maximizing application performance to all of our offices. With virtualization, we can guarantee consistent global support while reducing overall desktop and maintenance costs. About a decade ago, we therefore embarked on a major rollout of Citrix (formerly presentation server, now XenAPP) to all Linklaters employees.

Citrix performance in offices is directly impacted by the performance of the WAN. As the size of each office grows, so has the cost involved in delivering consistent and reliable performance to users. This has been particularly difficult in those locations in Asia and Latin America where WAN links are the longest and the worst quality.

Over time, Linklaters has experienced enormous growth in the sheer volume and size of documents that were being created and shared. Our document management system currently stores around 9 million documents with 30 million versions. With the increase of about 10,000 documents or versions a day, it's extremely difficult to keep pace with the volume of data that must be stored and shared using a variety of core business applications, including EMC Documentum, SAP, and Microsoft Office.

Compounding our challenges was a shift in the type of data being sent across the WAN, with an increased emphasis on real-time traffic. Our lawyers began using video and multimedia increasingly, which placed added demands on our network infrastructure. We saw a constant increase in Internet usage as our employees used more rich-media sites such as MSN, CNN and Lexis-Nexis. The firm is also gradually migrating from a mixed PBX environment to one built around Cisco's IP telephony offering.

The above trends made it extremely difficult to implement a successful disaster recovery plan. With a thin-client architecture, we did not have to worry about backing up remote offices. But we wanted to ensure that all data centers where protected in near real-time, with failover capabilities between them. We had some of the most sophisticated tools in the industry to achieve this objective, such as EMC's SRDF application. These tools required dedicated and cost network lines to support the replication.