WAN and virtualisation: A re-engineer’s utopia

Mired in network issues, outage anxiety and bandwidth headaches? Look at WAN virtualisation, where quality of service (QoS) rules, path selection and traffic shaping mean a new scenario for high-priority applications

Pratima Harigunani
New Update

Jatin Bakshi


Think back to the last time you had issues with work due to network connectivity. Did it affect your work? How did your react to this lag? A disruption in network connectivity, no matter how brief, can not only be aggravating but also potentially catastrophic for your business. In this connected age, it cannot be stressed enough, as to how dependent our businesses are on network connectivity. With this in mind, the first question you need to be asking is - are you doing all it takes to keep your network running at its’ best and avoid the losses that even a brief disruption can trigger?

Network failures can strike at any time—and their impact can be devastating for organizations of all types. In today’s centralized IT environments, lost connectivity can leave users unable to access crucial applications and data. Manufacturers can’t access the inventory data they need to respond to field inquiries. Healthcare organizations can’t retrieve patient information or test results at the point of care, or empower practitioners with the clinical systems they rely on. Retailers and financial services companies can’t process transactions. VoIP and other communication channels are severed, stranding both work teams and customers. Employees are cut off from the centralized services their work requires, and business grinds to a halt.

Yes, bandwidth issues can be tackled with WAN optimisation, but the reality is that many high-bandwidth business apps such as graphics-intensive design tools, VoIP and HD video don’t leave much room for optimization. Multiprotocol Label Switching (MPLS), which is reliable and provides fairly consistent performance is expensive. On the flip side, Internet connections via broadband technologies such as cable and DSL are much less costly, but reliability and performance are inconsistent. WAN optimization products accelerate performance and effectively increase bandwidth, but they can’t overcome all of the issues when the underlying WAN is unreliable or unavailable.


The key is WAN virtualization, a technology that logically binds multiple MPLS and broadband paths into a single logical path. With WAN virtualization, quality of service (QoS) rules, path selection and traffic shaping can be applied to ensure that high-priority applications always perform well. WAN virtualization can also ensure that all bandwidth on all paths is optimally utilized. In addition, critical business processes can be protected against network outages. If even a single path remains, key applications can be switched over in seconds and continue uninterrupted operation with no discernable impact on end user productivity.

How does one choose a virtual WAN solution?

The Virtual WAN solution should allow enterprises to create one logical WAN network by bonding together multiple network services and optimizing the use of each path.


It should also enable the enterprises to:

• Expand WAN bandwidth using economical and flexible cable, DSL and 4G wireless connections, in addition to trusted MPLS capacity, without sacrificing reliability and quality.

• Ensure that business critical applications always perform well, even when the underlying network paths are unreliable.

• Add or delete bandwidth quickly versus waiting on 90-120 days for service updates

How does the Virtual WAN achieve this?

While the advantages are great on paper, the heart of this article is to shed light on how a well-designed virtual WAN will achieve this. The WAN should be able to logically bond multiple, distinct WAN connections into one virtual link and send packets based on application needs and network performance. Let’s dive deeper into this:


• Utilize the idle link and make failovers seamless - A lot of enterprises today already have a back-up WAN connection at office locations. It could be another MPLS line from a different vendor or an internet line, but this back-up line is a resource that is fully paid for by the enterprise but remains largely idle except for when the primary link goes down. A virtual WAN will enable you to covert otherwise idle, back-up links to active ones.

• Scale WAN cost-effectively while maintaining desired reliability –MPLS availability is still an issue at most places and businesses or government organizations may need to commission branches in the farthest reaches of the world with highly reliable connectivity. By bonding together multiple heterogeneous satellite and other internet links, a Virtual WAN can diversify away the probability of all the links failing at the same time and thus prop an “always-on” branch, even in the absence of MPLS.

• Not all applications are equal – With the entire universe of applications and data flowing, not all traffic requires to be treated the same. A virtual WAN will ideally offload low priority tasks to inexpensive public internet paths by clearing up the primary MPLS and potentially improve the quality and experience of high-priority applications.


Additionally, a virtual WAN should be able to measure the network performance statistics to monitor the health of every link in each direction and give network administrators a complete dashboard view of the network’s entire mesh of data-centers and branches.

A well designed virtual WAN can increase effective network capacity and reduce costs substantially while improving the performance and reliability of business critical applications such as VDI, application virtualization, VoIP, video conferencing, ERP and CRM. So make sure you keep these pointers in mind whenever you decide to upgrade your architecture.

(Jatin Bakshi is Business Head - Cloud Networking at Citrix Systems. The views expressed here are solely of the author and Cybermedia does not necessarily represent them)

experts virtualization