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Remote users in WAN jam

01 Feb 2011

Big iron style consolidation, driven by major cost savings and enabled by virtualisation in the data centre, is forcing a serious rethink of wide area network (WAN) capabilities and the efficiency of what’s running over them. Moving back to a centralised computing model has resulted in many enterprises struggling with unflattering response times for mobile and remote office workers, with latency and data loss proving a major headache. According to several analysts, 2011 is an important year for businesses, telcos and service providers to adopt performance management and enhancement technologies to optimise and accelerate the services they deliver. The fact is many applications designed for the local area network (LAN) don’t do so well over longer distances and throwing bandwidth at the problems of congestion and distance, even in a managed services or cloud environment, is not the answer. For many the answer lies in WAN optimisation through deploying  smart ‘appliances’, or software, or cloud solutions to simplify different applications and file types on the fly. This may include application acceleration, compression, caching, wide area file services, packet shaping, and more efficient transport of protocols such as TCP and SSL. Uncertainty over definitionsIt’s still an evolving market however and there are some misunderstandings around the different techniques and solutions. Some early adopters remain frustrated after being pressured to purchase complex, expensive and unnecessary products that promised to make networks go faster, says John Crawford, New Zealand Sales Manager for Exinda distributor, Packet Technologies.Optimisation, he says, is not really about quality of service (QoS) – although that might ensure critical video, VoIP and database and accounting packages get optimum bandwidth – but is about caching, de-duplication and bi-directional packet shaping. However he recommends deploying tools to identify why a network is going slow in the first place (something traditional network management tools and most WAN optimisation offerings don’t deliver), before guessing at a solution or simply adding bandwidth.  "I don’t understand how a customer can spend $10,000–$20,000 a month on a WAN and not know what’s going on. Surely you would want some visibility if only to cost justify the need for the circuit?” What to leave behindMark Urban, Senior Director of Product Marketing for Blue Coat Systems told Telecommunications Review that ICT managers should start by acknowledging that some core applications have known problems. For example if you’re trying to push a lot of data over the line between Auckland and Singapore using Microsoft file-sharing, you know it’s going to be slow because the protocols are very chatty and there’s latency on the line.If you are trying to deliver SAP Business Objects the protocols can be inefficient with a lot of data being sent repeatedly. The answer, he says, is optimisation at application level."All the bandwidth in the world isn’t necessarily going to improve user response times because often the protocols are often too slow and not designed for working over a WAN,” says Urban. Generally, WAN optimisation saves money through reduced branch office infrastructure, reduced complexity and by cutting WAN bandwidth costs by between 60-90%.While cloud applications or SharePoint BPOS (business process online service) present a strong case for optimisation this has to happen at the enterprise network first before it hits the WAN.Optimisation is particularly beneficial when serving up corporate databases and applications such as Microsoft Exchange that rely on static files. Larger, frequently used files may be compressed and stored by appliances at each branch office, so they can be served up more rapidly.Stripping out the excessLike its competitors Riverbed promises to deliver LAN-like performance on the WAN by dealing with performance bottlenecks including latency. Riverbed’s acceleration software relies on patented techniques that remove redundant data and application ‘chatter’ through acceleration modules or, as Riverbed’s Chief Technology Officer Steven McCanne says, "The quickest trip you can take is the trip you don’t make”.Australia and New Zealand Managing Director Ian Raper, says before the company launched its Steelhead appliances in 2005, the market was largely focused on caching technology or distributing full file replicas across remote appliances, which soon came up against the laws of physics. "Since then, you’ve seen massive increases in scalability with our Steelhead model 7050 supporting 10 Gigabit Ethernet and 20,000 concurrent users from a single appliance.”Cisco Consulting Systems Engineer Conrad Bullock says WAN optimisation can help resolve problems with server and storage sprawl, unreliable links, remote data back-up, data centre consolidation, poor print performance and compliance issues around distributed data. He says virtualisation of the data centre has led to different delivery models, enabling WAN optimisation to be deployed on a virtual server or even embedded in a virtual switch layer. Cisco’s WAAS (wide area application server) runs on its own Unified Computing System servers and at branch offices through activating a software feature built into routers resulting in a ‘lighter weight’ deployment at lower cost.However, Bullock says it is important WAN optimisation isn’t viewed in isolation as it can bring significant benefits to the rest of your infrastructure. It could result in improved availability for remote sites, no longer having to maintain and manage remote servers, reduced storage needs, less management overheads, improved data protection and greater mobility for staff.Value for service providersWAN optimisation delivers an attractive case for the telco or service provider who can procure, deliver, install and configure a service and manage it on an ongoing basis with results that can be replicated throughout an entire organisation. Traditional telcos or carriers have been concerned that WAN optimisation might cannibalise their revenues by reducing bandwidth requirements. Bullock says Cisco’s focus has been more on improving application performance which has the potential to drive more applications over the WAN and ultimately boost bandwidth upgrades. In fact, he says WAN optimisation is one of the ways to make a service provider’s network ‘application aware’ and more suited to different customer software requirements. "They are able to offer SLAs (service level agreements) for delivery of applications rather than bits, making the service more relevant and more valuable.”Bullock says the hard and soft cost savings deliver compelling ROI for the managed service provider enabling a lower cost structure for IT and productivity and business process gains for the customer. He claims payback can be achieved in a matter of months. Riverbed, referring to an IDC analysis, claims an average of 6.9 months.Exinda has all the acceleration tools but bases its solution on a thorough analysis of the problem looking at netflow, call quality, application performance and latency issues, including how many megabytes users are downloading from which URLs."We sell a lot of products through the telcos because they realise visibility monitoring and reporting, traffic shaping and accelerating brings benefits to their partners who don’t have those tools,” says Crawford, of distributor Packet Technologies.The network may be running slowly because people are listening to streaming radio, using BitTorrent, YouTube or downloading Windows upgrades. "The ICT manager simply looks at our report, sees someone using a 1Mbit/sec stream, identifies it as YouTube and then identifies the user is Bob in accounts,” says Crawford.Crawford says once you have meaningful data, then you have the knowledge and power to make informed decisions about acceleration or bi-directional packet shaping and other ways of optimising networks.Riverbed’s Ian Raper says outsourcing WAN optimisation services allows telco service providers to shift from being a carrier, to delivering higher level managed business services "beyond the router and up the protocol stack”. Linking 3G and 4G mobile devices presents much higher and more variable latency and packet loss issues that can affect application performance. Most providers have ensured mobility is not orphaned when it comes to connecting into the WAN, providing specific tools to ensure performance consistent with working in the main office.It’s imperative to use mobile optimisation tools if you want LAN-like performance, says Raper. "The recent natural disasters in Christchurch and Queensland, Australia have demonstrated that being able to work remotely from an office is not just ‘nice to have’ but a critical business requirement.”Ahead in the cloudsThroughout 2010 most of the major WAN vendors released virtual optimisation software as an alternative to branch office appliances. Providers need to be able to rapidly ‘spin up’ and licence virtualised WAN optimisation appliances without having to add hardware to racks. In fact, says Raper, some of the largest cloud providers have a ‘no more hardware in data centres’ rule.Riverhead’s ‘anywhere acceleration’ vision for enterprise data and applications addresses performance issues in private, public and hybrid cloud environments. "In order to build scalability and virtualisation, cloud-enablement of products is vital,” says Raper.He says WAN optimisation can be integrated into the cloud to great effect to mitigate the ‘tyranny of distance’ as bandwidth and latency issues are amplified when the server is located in another part of the country or on the other side of the world.Cisco’s Bullock says virtualised WAN optimisation is particularly well suited to a cloud environment. "When applications are hosted in virtual infrastructure in a public or private cloud, this allows for an agile, elastic and multi-tenant deployment, supporting on-demand orchestration, using policy-based operations.”If applications are offered through the cloud, software appliances can be delivered dynamically from within a data centre to optimise performance, says Blue Coat’s Urban. "You have to be close to the user because it’s the last and first mile that are the biggest constraints in WAN use. However, optimising in the cloud only takes care of half the problem.”Optimising public cloud applications is far more complex than the private cloud. Urban says it’s better suited for delivering songs or rich media content to a large consumer base and not much help to the enterprise currently. He’s confident, however, that will change as there’s a rapidly growing case to have cloud delivered applications accelerated. "The minute you lose control of the data centre you have to do it differently.”He says Blue Coat’s asymmetric cloud optimisation can speed delivery of cloud applications from a single point to branch or remote users. "If I’m at a remote site and 50 people are using SharePoint BPOS, Blue Coat can make it 20-50 times faster and save lots of bandwidth.”Video invasion underwayJust as the right tools are being deployed to help WAN owners and providers cope with IT consolidation and cloud-based distribution the next bandwidth gobbling wave is already rolling in. Video now comprises over half of all network traffic both inside and outside the enterprise; much of it is legitimate training and communications media but recreational traffic is now spiralling out of control."We view video as the single biggest change in networking, exceeding delivery of applications by orders of magnitude,” says Urban. If someone’s watched a YouTube or compliance training video, specialised optimisation technology can immediately split that out to 100 users through a branch office cache with no impact on the network, he says.The rapid adoption of social networking is also adding complexity to the WAN optimisation mix. "Five years ago you might have blocked this kind of activity but workers across the world are now using social networking and it’s being accepted. Who’s really going to hassle an employee for checking their Facebook page or updating their wall?”In fact IT and business are trying to leverage social networking for their own use but in doing so will need to achieve some level of control to isolate and restrict gaming and video streams that are often associated with Facebook. With the right tools you can have greater confidence that only the traffic that needs to be on the network is doing the circuit optimally.The return to centralised computing, along with virtual and cloud-based environments, clearly frees up resources and if you can reduce application or file access from between two and three minutes to between two and three seconds, there are obvious productivity and ROI gains. WAN optimisation is a timely solution to deal with network performance issues, but looking at longer term traffic trends and bandwidth needs may help future proof that investment to ensure you’re not caught short.