Leading Indian business process outsourcing (BPO) player WNS Global Services has come a long way from its initial days as British Airways' captive unit. Headquartered in Mumbai, WNS has presence in international locations such as North America, the United Kingdom, the Philippines and Sri Lanka. WNS also has offices in Indian cities such as Bengaluru, Chennai, Gurgaon, Nashik and Pune. With such business growth, WNS' legacy storage could not cope with the BPO's humongous data growth. Hence, storage virtualization became the right mechanism for WNS to tackle humongous data growth and management of legacy devices.
Burdens of growth
"In the initial days, we used homogenous environments such as file servers integrated into the customer's environment. No complex infrastructure existed around storage, either in terms of the number of customers accessing storage or types of storage equipment," says Arvind Sood, chief technology officer of WNS Global Services.
WNS' storage requirements grew as the business expanded into international markets, which required the addition of a substantial storage infrastructure. As the infrastructure became difficult to manage, WNS' IT team undertook several initiatives in the past few years to tackle growing storage requirements and centralize management.
The decision and its translation
Due to maintenance overhead and management expenses, it was critical that WNS' IT team come up with an alternative to save operational expenditure. "Once we took the storage consolidation decision, we did a proof of concept. We then started the storage consolidation process. From the technology perspective, that way we defined our business need. So we did an ROI to understand accrued savings. Since we monetized the entire procedure, it allowed us to greatly simplify storage management," Sood says. WNS did not involve external consultants, since the internal core IT team handled the evaluation.
For selection of the right vendor, WNS focused on scalability and reduction of maintenance costs. Apart from this, the commercial aspect also played a major role in the selection. Commercial parameters such as up-front, recurring and support costs were taken into consideration. The company also conducted a total cost of ownership calculation for each planned investment.
When WNS decided to opt for storage virtualization, convincing different stakeholders was a major challenge for Sood's team. At WNS, several business stakeholders have to be involved before any changes can be undertaken in the business environment. "The internal technology unit that manages implementations is the first entity. Then we have to consult the business unit. You also need the customer's permission. Since taking permissions across different customers is a fairly complex exercise, we set up mini groups to deal with each set of customers and provided them with the work checklist," Sood says.
On the technical front, migration of huge volumes of information to the centralized server was a challenge. It was also critical to train people on an ongoing basis to ensure that they access the right information. "Hence, we had to grow gradually on a function-by-function basis across each location," Sood says.
WNS' storage virtualization project started in early 2007, and a substantial part of the project was finished by mid-2008. Since managing huge data volumes has been WNS' biggest challenge, the BPO implemented a storage area network from Hewlett-Packard Co. and network-attached storage (NAS) from Network Appliance Inc. "Our requirement was in excess of multiple terabytes. Today, we have a combined NAS and SAN capacity of approximately 70TB," Sood says.
WNS has implemented comprehensive storage virtualization at its larger locations like Mumbai, Pune and Gurgaon, which require storage virtualization because they need to service multiple customers. "Now we have gone from physical storage to virtual storage, with dedicated segments for each customer environment," Sood says.
WNS' storage virtualization architecture runs on a hardware level. Both storage systems (SAN and NAS) are part of the setup. Each client has distinct virtual storage infrastructure to ensure data privacy. SAN handles the customer databases, whereas WNS' file servers run on NAS. Network security and client confidentiality are taken care of at the network level through dedicated virtual local area networks and Microsoft Active Directory-based authentication.
According to Sood, storage virtualization helped WNS reduce its operational costs and simplify its data management processes. Due to the initiative, WNS has also retired part of its legacy storage, thus reducing overhead.