Solution Brief. Solving Application Performance Problems with Managed WAN Optimization. Vicki Jones Senior Product Manager Global Crossing

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1 Solution Brief Solving Application Performance Problems with Managed WAN Optimization Vicki Jones Senior Product Manager Global Crossing January 2010

2 A ssuring good performance for applications delivered over Wide Area Networks requires more than adequate bandwidth. The ultimate goal of any enterprise network infrastructure is to deliver applications effectively to users. That s easy within a building or campus since LANs have plenty of bandwidth and almost no latency. But maintaining an acceptable level of application performance at remote locations is a challenge for many organizations. Bandwidth is limited, but more importantly, network latencies become unavoidable with increasing distance. A major part of the problem is that many of today s WAN applications were designed for LANs and use WAN resources inefficiently often very inefficiently. By reducing or eliminating these inefficiencies, WAN optimization technologies deliver realworld improvements for business applications between four and 55x (Source: Juniper Networks). Application inefficiencies take several forms, so WAN optimization uses a set of technologies which address the problems in multiple ways without requiring additional bandwidth. Global Crossing s WAN optimization techniques include: Compressing transmissions and storing repeated patterns of data locally to avoid retransmissions Substituting more efficient transport protocols for the WAN portion of the data path Sending larger bundles of data instead of dribbling it out Gaining visibility into how bandwidth is being used and prioritizing critical applications This paper introduces WAN optimization by examining who needs it and why, how the various technologies deliver their benefits, and why a fully managed solution from Global Crossing is a particularly cost-effective way to implement WAN optimization without enterprise-wide circuit upgrades. Who needs WAN optimization and why? The short answer is that almost every organization that uses a WAN can gain significant benefits from WAN optimization. In some cases, organizations that are rolling out new bandwidth-sensitive and latency-sensitive applications may find that the new apps will not work properly without WAN optimization even if small-scale pilots have been successful. Here s why: Not too many years ago, most applications used the WAN sparingly. Before real-time traffic like voice, video and desktop sharing became common, low-bandwidth applications were the norm. Enterprise apps mostly used a client/server approach to computing which relied on each user s PC to run and display the applications. Only occasionally did remote workstations reach over the WAN to fetch a record, make a transaction, or send and receive . As 1

3 a bandwidth provider, Global Crossing (and our competitors) would be happy to sell you more bandwidth, but increasing capacity isn t always the optimal solution. New web-based applications put pressure on the WAN Now client/server-style computing is in retreat and on the rise are Software as a Service (SaaS), cloud computing and Web 2.0 applications. The impact on the WAN has been huge. Now every element of every web page must be transmitted over the WAN. When you think of how many times web-based applications download the same image files of logos, icons and buttons, you can appreciate the potential to dramatically reduce the bandwidth requirements of web applications by serving that repetitive data from a local cache. Organizations that attempt to add voice and other network-intensive applications into this pattern of WAN use may not succeed without WAN optimization because so much bandwidth is used by needless retransmissions. Distributed organizations reap greatest gains Organizations that are more geographically dispersed gain the most from WAN optimization because network latency is generally proportional to the distance between sites. Longer latencies provide more room for improvement, which is why customers who use satellite links experience out-sized benefits. At the other extreme, enterprises that connect locations through a Metro Ethernet service already enjoy low-latency LAN-like service, so there is little potential for meaningful acceleration. However, for the majority of sites that are separated by hundreds or thousands of miles, WAN optimization delivers impressive gains because latency quickly hobbles performance as much or more than bandwidth limitations. WAN planning and design efforts have traditionally centered around bandwidth utilization. However, latency plays a bigger role in determining application performance, especially in global WANs. Mark Fabbi Vice President and Distinguished Analyst Gartner WAN latencies are the silent killer Research firm Gartner refers to latency as the silent killer of application performance in a report of the same name 1. By itself, WAN latency is not necessarily a problem. A single round-trip isn t much delay; after all, people routinely converse on phone calls halfway around the world. Yet many applications now being run over WANs use chatty protocols designed for LANs. These LAN-oriented protocols require exchanging many requests and acknowledgments between workstations and servers to move a single block of data. Even in an uncongested, high-bandwidth WAN, the latency involved in each pair of requests and acknowledgements can add up to frustratingly long delays, even for users only hundreds of miles from their servers. Most applications use chatty protocols because they were designed to run on local area networks where short distances and speeds of 100 Mbps or faster hide the delays. But workhorse Internet protocols such as HTTP and HTTPS are overly chatty in today s networks. Their ping-pong volleys of requests and acknowledgements were designed to minimize retransmissions in the early days of IP networking when packets were often lost. Now, however, packets are rarely lost and more efficient error detection and correction methods eliminate the need to constantly check the receipt of every byte. 1 Latency: The Silent Killer of Application Performance. Gartner, Inc. 14 September

4 Ironically, even the mainstays of WAN applications use chatty protocols designed for LANs. For example, Exchange and Microsoft s drag-and-drop file transfer protocol, CIFS the transport backbone for many collaborative applications are prime examples of applications which can be accelerated. Applications that reap the greatest gains Applications which transmit repetitive data and use chatty protocols benefit most from local caching and protocol substitution. These include: Order processing Customer Relationship Management (CRM), and other database-intensive applications Enterprise Resource Planning (ERP) and HR management Content and document management systems including applications that push new content to multiple users Data replication and data backup services Web-based and cloud computing applications including SaaS Bandwidth reductions for the above applications along with WAN optimization tools that adjust the priority of applications allow new network-intensive applications to succeed, including: Voice Video Desktop sharing and other collaboration services The overall benefit of WAN optimization is to improve performance of WAN applications, get greater throughput from existing WAN services, and reduce the need for WAN upgrades. WAN optimization is now a top priority for many CIOs CIOs of major organizations have recognized the need to improve WAN communications to speed applications. According to a study by Merrill Lynch, CIOs now cite WAN optimization as their fourth-highest priority project, behind only security and storage initiatives: 3

5 Figure 1: CIO Project Prioritization on a Scale of 1-5 (Merrill Lynch Study) The ability of WAN optimization to help customers ensure the success of their applications makes this managed service a foundation of Global Crossing enterprise offerings. WAN optimization technologies deliver impressive real-world benefits Global Crossing evaluated WAN optimization technologies from leading network vendors and chose the Juniper Networks WXC Application Acceleration Platforms as the basis for managed WAN optimization services. As a marketleading WAN acceleration vendor, Juniper s WXC appliances implement the most comprehensive set of application acceleration technologies to deliver the greatest benefit across the widest range of applications. The Global Crossing and Juniper solution addresses the challenges of WAN optimization in four ways: 1. Compression and Caching Molecular Sequence Reduction The patented Molecular Sequence Reduction (MSR) compression and Network Sequence Caching technologies enable the WXC Series to deliver up to a 100-fold increase in effective WAN capacity, providing immediate congestion relief for all IP-based traffic. The appliances use the MSR algorithm to recognize repeated data patterns and replace them with short labels. The receiving appliance reverses the process by translating the labels back into the full data sequences. Network Sequence Caching A similar process called Network Sequence Caching extends the MSR approach a step further by caching even more data patterns on a highperformance hard drive. This creates many more possibilities for pattern recognition and substitution over longer periods of time. In this way, the repeated patterns within a large attachment sent to 20 different recipients at a branch office will be served from cache instead of being transmitted. That generates an immediate 95% bandwidth savings and users will appreciate the speed of document delivery. It is important to note that the Juniper appliances do NOT cache actual files. Instead, they cache data streams or sequences of bits. This is an 4

6 important distinction for security, performance and scalability reasons. Also, since it s not based on files, the appliances can compress and cache any IP-based traffic, unlike other technologies that only work on a few protocols. These applications often require WAN acceleration to be successful: Autodesk AutoCAD Computer Associates XOsoft Data Domain DICOM EMC Celerra EMC Documentum Lotus Microsoft Exchange Microsoft SharePoint NetApp SnapMirror Oracle Peoplesoft SAP Siebel SQL Symantec Backup Exec Symantec Veritas Volume Replicator Source: Juniper Networks 2. Acceleration Packet Flow Acceleration To move data from place to place, a wide range of applications rely on TCP, the Transport Control Protocol. The protocol is so prevalent that the Internet is often referred to as a TCP/IP network because TCP and its complementary protocol, UDP, move most Internet traffic. The Juniper equipment installed to run Global Crossing managed WAN optimization services accelerate both TCP and UDP. Accelerating TCP is particularly important because the gains can be so great. One of the characteristics of TCP that made it ideal for the early days of the Internet has now become a drag on performance across today s wide area links. The problem is that TCP relies on receiving an acknowledgement before sending the next bit of data, and because it sends so little data at a time, many transmissions and acknowledgements can be required to move an entire file. At the sending location, Global Crossing s Juniper technology terminates each TCP session at the WXC Series appliance and substitutes more efficient protocols to send the data over the WAN to the receiving appliance. At the receiving end, the Juniper appliance translates it back into TCP. Since the appliances are local to the servers at one end and local to the workstations at the other, the only time the traffic uses TCP is when it is running on low-latency LANs. Application Flow Acceleration Application Flow acceleration speeds up the applications themselves, not just their use of TCP or other protocols. This enables Juniper equipment to accelerate Microsoft CIFS (the drag-and-drop file transfer protocol), MAPI (Outlook s underlying protocol), HTTP and SSL and their combination, HTTPS. One of the reasons Global Crossing chose Juniper s technology for its WAN optimization service is because Juniper is the only WAN acceleration vendor to accelerate all of these protocols. 3. Application Control Quality of Service At some point, even compressed and accelerated circuits will become congested. Left unmanaged, this congestion, of course, will impact real-time applications. It can lead to lost packets which disrupt voice traffic and even drop calls. The Juniper technology enables Global Crossing to assign up to 16 priorities and classes for different types of traffic. This enables Global Crossing to customize WAN optimization service for each customer, prioritizing their critical latency-sensitive applications such as voice traffic over and other less timesensitive applications. 5

7 Policy-based Multipath Policy-based Multipath allows traffic to be directed to preferred network paths. Latency sensitive traffic (such as VoIP) can be transmitted over a preferred link, while less time-critical applications (such as ) can be directed to other paths. 4. Visibility Detailed reporting and application control One of the main advantages of the Global Crossing WAN optimization service is the insight that it provides to customers into how their WAN links are being used and the ability to apply that knowledge to tune the WAN optimization service to gain maximum efficiencies. Visibility into and control over the WXC Series Application Acceleration Platforms is provided via embedded WebView device management and the powerful WX Central Management System (WX CMS) software. The WX CMS software provides visibility into application performance across multiple WXC Series devices, enabling extensive configuration, monitoring and management capabilities. The Central Management System is fully integrated with Global Crossing s ucommand customer portal. Figure 2: Reports detail the amount of compression, show top applications in a pie chart, and plot the distribution of WAN latencies and packet loss. (Source: ucommand reporting interface) WAN optimization services are available in a variety of configurations The Global Crossing WAN optimization service includes equipment configured to suit your location, and provides fail-safe operation. In the event of a failure, the WXC Series device automatically converts to bypass mode, allowing traffic to pass through untouched. 6

8 Global Crossing managed WAN optimization services deliver outstanding value for these key reasons: Complete Other WAN optimization services and technologies typically focus on only a piece of the WAN problem, but the Global Crossing solution using Juniper equipment provides a comprehensive approach that covers everything from chatty protocols and QoS to traffic visibility and latency Integrated Global Crossing tunes the performance of each device to maximize the benefits at each site Fully mature Global Crossing uses proven, marketleading technology to assure successful implementations Easily integrated The service operates transparently with existing network equipment and client and server devices. Flexible Global Crossing WAN optimization services can be rolled out to only a few key sites or deployed widely Fully managed Experienced Global Crossing staff install all equipment, tune application performance over the WAN, monitor and manage optimization parameters 24/7 Visibility CMS is fully integrated with ucommand, so you can monitor the performance of the device and download reports anytime. Figure 3: WAN Optimization supports both inline and off-path configurations, asymmetric deployments and secure IPsec configurations over public networks. Transparent to other network equipment, WXC Series appliances can be installed directly inline between a LAN switch and WAN router, or deployed offline by attaching to an available port on the router. The Global Crossing service also works effectively alongside VPN servers, firewalls, and other security devices to optimize traffic before it is encrypted. Invite Global Crossing to evaluate the benefits you can expect Experienced Global Crossing Sales Engineers are available to examine your mix of WAN applications to determine the likely benefits you will experience with WAN optimization and plan its rollout. Global Crossing can install the equipment at each site without affecting your normal operations and then activate acceleration for sets of applications in phases matched to your schedule. Global Crossing WAN experts will tune acceleration parameters and set application priorities to maximize your benefits. Skilled operators at our Network Operations Centers will monitor and manage the utilization of all your WAN links 24/7 and provide periodic reports of your network use and the throughput gains you are experiencing with WAN optimization. For more information about Global Crossing WAN optimization managed services, please contact your account manager or visit globalcrossing.com/thinking_ahead/thinking_ahead_leveraging_network_ investments.aspx.

9 Global Crossing Holdings Ltd. Global Crossing and the 7 Cable Design are registered trademarks of Global Crossing Holdings Ltd. and ucommand is a registered service mark of Global Crossing Ltd. in the United States and other countries. Some services are subject to geographic availability. Other restrictions may apply. WO0110