WAN : Getting Ready for Speed?

With continuous performance improvements in PC and LAN technology-such as

gigabit Ethernet, multi-core processors, and better desktop software -delivery

of applications and data within a locally connected environment is quick and

easy. However, the same cannot be said when it comes to maintaining an

acceptable level of application performance across the WAN. In fact, this is a

consistent challenge for many organizations and one where throwing more

bandwidth at the problem is not the answer.

The Scourge of the Network



The key challenge for IT managers is the perennial networking issue known as

latency-the silent killer of applications. Latency is simply the result of

physics, 'namely, the speed of light over longer distances combined with

store-and-forward hops across routers. And because reducing latency itself is

not possible, IT managers need to consider reducing the impact latency has on

the behavior of enterprise applications.

In addition, there are four areas that have slowed application performance

over the WAN for years:

• Application performance visibility: If IT managers do not know what
  
  is happening in the distributed enterprise network, they will not have a clear
  
  idea how to improve performance.
• Application contention: Competition between applications will
  
  increase, causing business-critical applications to be slowed by non-critical
  
  traffic.
• Bandwidth limitations: WAN links offer limited bandwidth. New
  
  application rollouts, which are inevitable in any large organization, will
  
  consume even more.
• Availability: Without a connection to the data-center or the rest
  
  of the enterprise, work simply stops. Creating an application-fluent
  
  infrastructure, which understands the content and transactions at network
  
  layers 4 through 7, is an absolute necessity to deliver transaction
  
  completeness.

Therefore, an application acceleration solution is not about guaranteeing

uptime or throughput or transactions per second, but providing the user with a

consistent, high-performance, reliable and secure application experience.

The Application Acceleration Attraction



As more organizations begin to understand that buying more bandwidth is not

the answer, they have turned their attention to address the real user

concern—faster transfer of files within the WAN.

On this premise, application acceleration promises to provide substantial

operational savings by eliminating the need to deploy servers in remote branch

offices, dramatically simplifying system maintenance, management and

administration with a smaller IT staff. With an application acceleration

solution, detailed insight into the WAN environment will allow the IT manager

the ability to monitor and record activity and understand how the network,

remote users, and applications interact.

WAN Best Practices



With increasing budget pressure, application acceleration solutions have

begun to be viewed as attractive in removing WAN bottlenecks. It is all about

knowing how to optimize the WAN environment. In our 'Best Practices for WAN

Optimization' whitepaper, we listed a set of best practices that enterprises may

want to consider when implementing a WAN optimizing solution. Briefly, the best

practices are:

• Consider compression and caching techniques rather than increase the
  
  pipe size: The default option for increasing the size of the WAN link has
  
  been to upgrade the capacity of that constrained link. However, this is
  
  expensive. A cost-effective alternative is to use market-leading compression
  
  and caching to gain instant WAN capacity on the existing network. Based on our
  
  experience, and depending on the application mix, businesses typically gain a
  
  two to four fold increase in capacity on existing WAN links by eliminating
  
  repetitious data. Some enterprises have seen as much as a 10-fold increase.
• Reduce inefficient protocols: To speed transmissions between
  
  business applications, WAN optimization and application acceleration platforms
  
  need to overcome the impact of latency. To do so, an application acceleration
  
  platform requires both TCP acceleration to benefit a broad range of
  
  applications and application-specific acceleration to speed applications whose
  
  Layer-7 protocols are less efficient than TCP.
• Quality of Service (QoS) support and configuration: Instead of
  
  relying on per-flow manipulation of traffic with current QoS policies,
  
  enterprises should consider approaching QoS and bandwidth allocation with a
  
  pragmatic, solutions-based orientation, making sure that mission-critical
  
  application traffic arrives where it needs to within the required service
  
  level agreement (SLA). This approach strikes the needed balance between
  
  performing QoS in the most appropriate device-the WAN optimization
  
  platform-and keeps implementation simple.
• Choice of deployment: Delivering applications throughout a
  
  distributed enterprise requires great flexibility in options for network
  
  placement and configuration, transport support, and capacity ranges. Thus, for
  
  network placement, IT must have the choice to deploy WAN optimization
  
  equipment either on the network between a LAN switch and WAN router, or
  
  attached to a switch and router in a one-armed fashion.
• Usability: Given the increasingly pervasive deployment of
  
  application acceleration platforms throughout an enterprise's locations,
  
  having a system that's easy to use is vital. A number of essential factors
  
  determine a device's usability, including an intuitive interface, automated
  
  configuration and deployment capabilities, and synchronized communications
  
  among platforms. A good application acceleration solution should be able to
  
  pre-stage configurations centrally via templates and then have remote WAN
  
  platforms download them automatically.
• Maximize the value of multiple WAN links: Enterprises increasingly
  
  seek to take advantage of hybrid public/private WAN transports, but need the
  
  assurance that key performance criteria will still be met. To make effective
  
  use of both paths, IT needs to apply business policies to each link and
  
  monitor performance. Most WAN optimization platforms overlook this WAN
  
  deployment scenario and fail to help IT make full use of these dual links.
• Get comprehensive insight to WAN traffic patterns: Defining
  
  policies for optimizing traffic flows over the WAN requires that IT understand
  
  the actual traffic flows. Monitoring tools that provide unified insight into
  
  distributed applications and networks are essential to effective application
  
  delivery.
• Scalability: Because enterprises have a variety of locations that
  
  range in size, applications, and link types, businesses need a wide range of
  
  WAN optimization and application acceleration platforms. Thus, IT should look
  
  for platforms that scale the performance of a wide cross-section of the
  
  enterprise's applications.
• Security: Enterprises no longer have the luxury of securing just
  
  their private WANs and avoiding the Internet for business transactions.
  
  Instead, they need to make use of both transports. Thus, IT needs tools to
  
  make all transports secure enough for these business transmissions. For WAN
  
  optimization platforms, two aspects of security are critical: securing the
  
  device itself and securing the data that traverses the device.

Based on these best practices, the ideal WAN framework should include

compression and caching, acceleration, application control, and visibility. As a

result, this integrated approach allows IT to successfully provide LAN-quality

application delivery across distributed enterprises. Therefore, by recognizing

application acceleration as a strategic business asset, IT managers can address

problems of organizational efficiency with high-performance networking that

helps drive market share, revenue and profit.

Sanjay Jotshi,



The author is director of Enterprise and Channels, India & SAARC, Juniper

Networks



vadmail@cybermedia.co.in