How To Choose A Wan Optimization Controller

Transcription

1 How to Pick the Right WAN Optimization Solution for Your Organization 3 April 2013 ID:G Analyst(s): Bjarne Munch VIEW SUMMARY WAN optimization controllers continue to have significant differences in functionality. Network managers who choose the wrong solution for their environments will have to deal with unresolved performance issues, suboptimal performance resolution and higher costs. Overview Key Challenges Although the WAN optimization market is mature, with a large number of viable solutions, there remain differences among all vendors in their support for all functional areas and their adoption of new functionality, making it a continued challenge for network managers to stay informed. Mapping the evolving vendor solutions to specific enterprise needs and use cases can be challenging, given that all vendors claim to provide a panacea for all environments. Recommendations Do not choose a WAN optimization solution based on a preconceived vendor preference, as even leading vendors are not leaders in all functional areas. Be sure you have current information, including product road maps, about WAN optimization products, as this is a constantly evolving market. Define objectives and functional requirements as the first step in selecting a WAN optimization vendor. Then create your WAN optimization shortlist based on a vendor's ability to meet these functional requirements. Perform a live trial of preferred products before committing to the purchase. Participate actively in the installation and configuration of each proof of concept to understand the complexity of deploying each solution. Introduction WAN optimization is a vibrant market, equal to more than $1.2 billion in annual revenue. The Gartner Magic Quadrant for WAN Optimization Controllers for 2012 includes eight appliance vendors, but several other vendors are viable choices. Despite being a large and fairly mature market, there is a significant variation in the functions each vendor supports. 1 For the last eight to 10 years, WAN optimization controllers (WOCs) have been a product area consuming similar and adjacent functions, such as application acceleration, caching, compression and deduplication, traffic visibility, control, measurements, content delivery network (CDN), video delivery and WAN path control. This trend of expanding product functions is likely to continue until at least While this trend offers network managers an opportunity to simplify their solution deployments, it also provides a challenge to ensure that your company selects the right product with the right functionality. 2 In this research, we outline key functional evaluation criteria to ensure that network managers select the right product (see Table 1). Table 1. Summary of Select Use Cases and Related Issues and Solutions Use Case Key Objective Key WOC Functions Reduce WAN cost To reduce WAN costs by reducing bandwidth usage Compression and deduplication Caching Optimizing streaming video delivery STRATEGIC PLANNING ASSUMPTION The WAN optimization market will remain in constant and significant change until at least EVIDENCE 1 The evaluation of vendors' support for specific functionality is based on a survey of the vendors included in the Gartner "Magic Quadrant for WAN Optimization Controllers," as well as a detailed review of these vendors' product descriptions and data sheets. 2 This is evident via recurring client inquiries about WAN optimization. A typical client inquiry question is: "Which vendors should I look at if I want to solve this problem?" In other inquiries, clients have told us they chose a WOC based on a preconceived vendor preference, but then, for example, found that problems related to a poorly performing SharePoint were not solved, because the vendor did not support SharePoint optimization. We have seen clients shortlist two vendors with a price difference of close to 50%, where the vendor with a low-priced product was just as good a fit as the vendor with an expensive offering. NOTE 1 COMPRESSION VERSUS DEDUPLICATION Compression and deduplication are similar. Both methods analyze the data before transmission for repetitive byte patterns and replace them with small references for the transmission: Compression identifies redundancy in a specific file being transmitted and then removes those redundancies. Typically, standard algorithms such as gzip and LZ are used for compression. Deduplication works by identifying redundancy within all files being transmitted, and the algorithm looks for longer byte patterns than compression. Typically, proprietary methods are used for deduplication. Because deduplication works generically across all files identifying long patterns, significantly higher compression is possible; however, larger memory is also required. NOTE 2 VIDEO STREAMING Depending on the video type and format, the bit rate for a video stream can range from 375 Kbps up to 6 Mbps for HD video. If several employees are watching a stream at the same time, the network impact is equally higher (e.g., 10 people watching a 375 Kbps stream add more than 3 Mbps). To reduce network impact, vendors implement media servers to manage the media stream. This needs to be done for each streaming protocol in the network. There are several dedicated streaming protocols e.g., the traditional Real-Time Streaming Protocol (RTSP), Real-Time Transport Protocol (RTP) and Real-Time Transport Control Protocol (RTCP). Increasingly, more enterprises are using Web- and HTTP-based video streaming via systems such as Microsoft Silverlight, Apple QuickTime and Adobe Flash using protocols such as HTTP Live Streaming (HLS), HTTP Dynamic Streaming or Smooth Streaming. Enable data center consolidation To ensure that application performance remains acceptable after the application has been moved from a decentralized deployment to a centralized deployment Application acceleration NOTE 3 THE WAN CONNECTION IS CRITICAL TO FAST STORAGE REPLICATION Off-site storage backup often requires very large data volumes to be transferred within a limited time window to minimize the time the application is out of service. This may be done at a set time during each day or several times during a day to reduce the risk of data loss. A full asynchronous database backup may involve 1 of 5 22/08/ :27

2 Use Case Key Objective Key WOC Functions Enable enterprise mobility strategies Enterprise disaster recovery Source: Gartner (April 2013) To optimize user experience of applications being accessed via a mobile device To minimize the enterprise disaster recovery time Asymmetric Web acceleration Symmetric software-based WAN optimization controller (SoftWOC) client Compression and deduplication several 100GB of data, which can take several hours of backup time. The size of the WAN connection, as well as latency of that connection, has a significant impact on achievable throughput. Typically, the distance between the primary and secondary data centers is between 10 km and 200 km. The general backup latency requirement is 50 ms or less. Gartner client inquiries indicate that around 40% of enterprises perform storage backup and replication over a shared WAN (MPLS), while the rest use a dedicated WAN (Ethernet). For backup performed over a shared network, QoS and traffic management are needed to ensure bandwidth allocation for the backup traffic. Analysis Start the WOC Selection Process by Defining and Prioritizing Use Case Objectives and Functional Requirements The only way in which network managers can properly select a WAN optimization solution is by clearly identifying their key objectives and the functional requirements needed to meet these objectives. We evaluate four specific use cases and establish high-level functional requirements for each use case. Reduce WAN Costs Controlling WAN costs is a key focus for enterprises. One aspect that many network managers investigate is using bandwidth reduction to avoid upgrading a WAN link. This is done via three different functions: (1) caching, (2) a combination of compression and deduplication, or (3) optimized delivery of streamed video content. Bandwidth reduction is about reducing the amount of data being transmitted across the WAN. While WAN cost control is a typical driver, reducing the amount of transmitted data also reduces the user's latency experience. Enable Data Center Consolidation by Improving Application Response Times Gartner clients frequently discuss application performance problems during inquiries. Often, these discussions are brought up in connection with data center consolidation and centralized application deployments. There can be several causes for application performance problems, which also means there is no single solution. The functionalities typically used to solve these performance issues are application acceleration and network traffic control. Review Enterprise Mobility Strategies to Improve Efficiency of Mobile and Remote Workers Mobility and use of personal devices continue to see strong enterprise interest. According to "Hunting and Harvesting in a Digital World: The 2013 CIO Agenda," enterprises are already migrating to laptops and mobile devices as the key user devices. In combination with increased adoption of bring your own device (BYOD), cloud computing and working outside the office LAN, this means that network managers need to consider how to deliver business applications with acceptable performance to individual employees. This can be done via two dedicated mobile solutions: Web acceleration or SoftWOC clients. Minimize the Enterprise Disaster Recovery Time Replicating storage data for disaster recovery has a fairly simple goal: Move data from primary storage to secondary storage, and back, during disaster recovery as quickly and securely as possible to meet the enterprise recovery time objective, such as less than one hour to recover a business process after failure. The faster that the replication process can take place, the less impact and downtime there is on the business process and for end users. WAN optimization is often used to assist in this replication via dedicated functions for acceleration of storage replication. Use Defined Functional Requirements to Shortlist WOCs Having defined specific functional requirements, the next step is to identify specific features and capabilities with vendors' products that can best meet the requirements. Multiple Ways to Reduce WAN Bandwidth and WAN Costs Use Caching Caching has been used for many years and is still supported in various manners by WOC vendors, such as Blue Coat, Cisco Systems, Citrix, Exinda and Riverbed. However, the types of caching have increased to meet the needs of current applications. Most WOC vendors support two types of caching: File or object caching stores or copies entire files or objects locally, and thus avoids transmitting the same file several times across the WAN. File caching is particularly useful for frequently accessed files or objects that are more static in nature, and can reduce bandwidth use by more than 90%. However, this is application-specific for example, HTTP content, images, streaming media objects or FTP files. Thus it's important to ensure not only that relevant applications are supported, but also that the device provides sufficient storage. Leading devices support up to 2 of 5 22/08/ :27

3 15TB of disk storage capacity. More vendors are planning to offer video caching functionality. Vendors should also offer content refresh and content distribution. Byte caching identifies frequently repeated bit or byte patterns across all content that is transmitted, and stores these byte patterns locally in a segment store. A key difference between the two types of file caching is that byte caching is done without regard to the relationship between file and objects, and thus caches byte patterns that appear in multiple files and file types. Byte caching also works on more dynamic files e.g., editing one word in a document removes the benefit of file caching, but leverages the byte cache. Byte caching and segment store are integrated components of compression and deduplication. Use Compression and Deduplication Compression and deduplication are supported by most vendors, including Blue Coat, Cisco, Exinda, Riverbed, Citrix, Ipanema and F5. Typically, these are implemented as an integrated two-stage process with a generic first-pass compression based on standard gzip, Lempel-Ziv (LZ) or similar algorithm, and a segment-store second pass based on a proprietary deduplication algorithm (see Note 1). To achieve the greatest reduction in data transmission, both processes must be employed. The performance of vendor-specific solutions is highly dependent on algorithms and actual implementations, but also depends on processing power and amount of memory supported by the appliance. Today, vendors usually use solid-state drive (SSD) flash memory for higher data throughput, and typically in the order of gigabytes to terabytes for high compression levels. Network managers should evaluate solutions in the context of enterprise-specific data content before making any assumptions about compression rates. Text can typically obtain a high compression rate, while graphic (picture) files (GIF, JPG, etc.), music files (MP3, WMA, etc.), video files (AVI, MPG, etc.) and other already compressed traffic achieve limited additional compression. It is not possible to compress encrypted traffic, and, thus, it is essential that the WOC support Secure Sockets Layer (SSL). As a general rule, data deduplication can reduce bandwidth needs by at least 60%. However, in many cases, bandwidth may be reduced by 80% to 90% or even more. Use Optimized Video Content Delivery Enterprise adoption of video continues to grow, with a predicted increase to 16 hours per employee per month by 2016, from 4.1 hours in This means that enterprises are interested in how to control and reduce the impact on the enterprise WAN (see Note 2). This adoption is for real-time video communications and streaming video, which is used for many different purposes, such as on-demand training and education, live video streaming of corporate events and live executive briefings. WOC vendors, such as Blue Coat, Cisco Systems, Citrix and Riverbed, are adding functionality to their appliances that better manage the network impact of high volumes of video traffic. In addition to traditional functionality for traffic quality of service (QoS), caching and deduplication, vendors are increasingly adding media servers to optimize video performance via stream splitting, video prepopulation and video caching. These techniques can reduce WAN bandwidth utilization by more than 90%. Enable Data Center Consolidation by Application Acceleration The typical source of application performance problems continues to be transport and application protocols that are not designed for high-latency networks (e.g., for one-way latencies above 50 millisecond [ms] performance degradation). Acceleration technologies can reduce the latency impacting end users by 60% or more. Most vendors perform TCP optimization, which essentially optimizes all applications. As a general guideline, these techniques can reduce latency impact up to 30% to 40%, depending on the implementation and the amount of memory available for TCP windowing. When combined with application layer latency compensation techniques, latency can be reduced by at least 60%. In addition to generic transport protocol optimization, network managers should look for specific application layer optimization, such as: Application protocol optimization, as well as content prepositioning, pipelining, read-head, writebehind for Messaging API (MAPI), Common Internet File System (CIFS), Server Message Block (SMB), Network File System (NFS), HTTP, etc. Virtual Desktop Infrastructure (VDI) acceleration, QoS and deduplication/compression of Citrix's Independent Computing Architecture (ICA), Microsoft Remote Desktop Protocol (RDP), VMware via Microsoft Remote Desktop Protocol (RDP), VMware PCoIP The result is significant acceleration of the applications. Expect 60% to 70% latency improvements in addition to the TCP improvement. Vendors include Riverbed, Blue Coat, Exinda and Cisco Systems. Improve Network Performance With Advanced Network Traffic Management As enterprise bandwidth utilization continues to increase by over 30% annually, network managers often struggle to maintain consistently good performance for their business applications. The issues are related not only to lack of bandwidth planning, but also to use of recreational traffic, such as viewing YouTube and seasonal sporting events online, which create unpredictable traffic patterns and traffic congestion. By deploying application-level bandwidth usage monitoring and combining it with application-specific traffic management, network managers can deliver consistent application performance for critical applications, while maintaining a high level of network utilization up to 80%. This area includes a range of traffic management capabilities, such as: Identify specific application traffic based on Internet Protocol (IP) address, port number, application-specific identification, URL and HTTP Display bandwidth utilization for each application broken down into WAN access or subnet, hosts and user 3 of 5 22/08/ :27

4 Classify applications and URL/HTTP content into priority classes and priority queuing, and tag applications for transport over the WAN Allocate guaranteed bandwidth or performance for specific applications, as well as manage bandwidth usage for all other applications Throttle/shape or block/allow traffic by application, ports, protocols, URLs, URL category, users, user groups, IP address, file type, Multipurpose Internet Messaging Extensions (MIME) type or time of day Vendors include Blue Coat, Exinda, Ipanema, Riverbed and Silver Peak. Network managers need to differentiate between vendors that only do priority tagging of applications and queue management, and vendors (such as Blue Coat and Exinda) that also perform active traffic control, such as shaping, throttling and blocking based on a range of configurable conditions. Support Individual Personal Devices There are two methods available to improve application performance for mobile users: An asymmetric solution is based on functionality in the current browser, and thus does not use a dedicated software client on the user device. All Web browsers support negotiation of compression on HTTP streams, typically using gzip and caching. In addition, Riverbed uses JavaScripts for Web page optimization, such as Cascading Style Sheets, images and merging Web page files for fewer roundtrips. This can reduce data volume by close to 50%, and reduce the impact of latency by up to 60%. Vendors include Blue Coat, F5, Radware and Riverbed. A symmetric solution is based on a SoftWOC client to be loaded onto the user device. A SoftWOC offers features similar to a branch office appliance, across all applications, not just browser-based applications, reducing latency up to 70%. These clients also support deduplication and can reduce data volume up to 90%. In addition to understanding specific feature support, network managers should evaluate support for OSs such as Windows CE, Windows XP, Windows 7, Windows 8, Apple ios, Mac OS and Android. It is critical to evaluate mobile device requirements for memory and processing power to perform application acceleration and deduplication. Vendors that offer a SoftWOC include Riverbed, Cisco Systems, Circadence and Citrix. Reduce the Enterprise Disaster Recovery Time With Date Center to Date Center Storage Replication Acceleration The purpose of WAN optimization in this context is to speed up the transport of high data volumes between data centers via data deduplication, IP/TCP acceleration and storage protocol acceleration for the relevant storage replication solutions from Dell, EMC, Hitachi Data Systems, NetApp, Oracle and others. While storage systems already perform block deduplication, WOCs can add byte-level deduplication. A key selection criterion is the data throughput the device supports. Therefore, network and storage managers should start by defining their throughput objectives (e.g., 300GB per hour). Vendors' marketing materials often focus on the speed of network interfaces as a key benchmark for the throughput that their appliances support. Currently, the largest interface available is up to 10 Gbps (see Note 3). However, the amount and type of memory supported by the device is equally, if not more, important than the throughput. Strong data reduction is paramount to fast replication (and thus throughput), and byte deduplication requires a large local store of very fast memory. Leading devices support up to 5TB of SSD. Vendors include Silver Peak, Riverbed, F5 and Citrix. Always Perform an On-Site Proof of Concept Before Signing the Purchasing Contract After compiling the vendor shortlist, network managers should test their preferred device before final purchase. The purpose is twofold: Network managers need to ensure that the device fulfills the specific functional needs of their use cases within the enterprise network environment. The enterprise networking staff needs to understand how easy or difficult it is to deploy and operate the device. There is a significant difference in how various vendors' devices are configured, deployed and managed. Therefore, network managers need to include this information in their final selection criteria. Testing is preferably done at real-world enterprise locations that provide a representative sampling of the enterprise network (connection type, application and content traffic types, latency and bandwidth characteristics). Alternatively, testing can be done on a test bed with a network impairment simulator to mimic typical and worst-case network conditions. Network managers first should establish a baseline noting their current application's performance and bandwidth use. Many WOCs monitor and report these parameters. During initial testing, the network team should find out if the device can report the impact on performance. The test should be performed over a few weeks, typically three to five, to ensure most workload conditions are tested. It is important to be prepared to fine-tune the device, as well as the applications and changes to the network, to gain optimum performance. For example, the testers may have to turn off application-based encryption and/or compression, use a particular port number with the application, change QoS settings in the router or increase WAN bandwidth for a certain class of end users. It is important that the enterprise network staff do not work in silos. They should work alongside the vendor or vendor partner during the test phase to get hands-on experience. They should include security staff in the proof of concept to understand and test the support of SSL, and the handling of 4 of 5 22/08/ :27

5 encryption keys and certificates. Finally, the enterprise network staff needs to report to the selection team about the complexity and time involved in operating the device or devices Gartner, Inc. and/or its affiliates. All rights reserved. Gartner is a registered trademark of Gartner, Inc. or its affiliates. This publication may not be reproduced or distributed in any form without Gartner s prior written permission. If you are authorized to access this publication, your use of it is subject to the Usage Guidelines for Gartner Services posted on gartner.com. The information contained in this publication has been obtained from sources believed to be reliable. Gartner disclaims all warranties as to the accuracy, completeness or adequacy of such information and shall have no liability for errors, omissions or inadequacies in such information. This publication consists of the opinions of Gartner s research organization and should not be construed as statements of fact. The opinions expressed herein are subject to change without notice. Although Gartner research may include a discussion of related legal issues, Gartner does not provide legal advice or services and its research should not be construed or used as such. Gartner is a public company, and its shareholders may include firms and funds that have financial interests in entities covered in Gartner research. Gartner s Board of Directors may include senior managers of these firms or funds. Gartner research is produced independently by its research organization without input or influence from these firms, funds or their managers. For further information on the independence and integrity of Gartner research, see Guiding Principles on Independence and Objectivity. About Gartner Careers Newsroom Policies Site Index IT Glossary Contact Gartner 5 of 5 22/08/ :27