getting the performance you need with vdi and byod - Spirent

GETTING THE PERFORMANCE YOU NEED WITH VDI AND BYOD Overcoming the Challenges of Virtual Desktop Infrastructure (VDI), Desktop-as-a-Service (DaaS) and Bring-Your-Own-Device (BYOD) August 2012

Rev. A 08/12

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Getting the Performance You Need with VDI and BYOD Overcoming the Challenges of Virtual Desktop Infrastructure (VDI), Desktop-as-a-Service (DaaS) and Bring-Your-Own-Device (BYOD)

CONTENTS Executive Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 End-User Computing Environments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Network Challenges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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Realistic Network Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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Benefits of Realistic Network Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 End-User Computing Technologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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The Impact of Underlaying Technologies . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Testing Challenges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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Realistic Testing with PASS Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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Getting the Performance You Need with VDI and BYOD Overcoming the Challenges of Virtual Desktop Infrastructure (VDI), Desktop-as-a-Service (DaaS) and Bring-Your-Own-Device (BYOD

EXECUTIVE SUMMARY End-user computing environments are evolving once again. Trends like consumerization and BYOD are driving a major increase in the number and type of devices connecting to company networks. At the same time, virtualization and cloud computing technologies used in end-user computing environments are placing new and often unexpected strain on WIFI, LAN, WAN and data center networks. Without realistic network testing, IT organizations will fail to achieve the benefits promised by VDI, DaaS and other modern end-user computing architectures. Realistic network testing involves accurately simulating statistically correct user loads, including both individuals and groups, while using real clients with the latest version of protocols. Successful testing also requires strategies as well as test tools that understand and address the many differences in applications, devices, users and architectures. Finally, to ensure higher-level objectives such as SLAs are met, realistic network testing of modern end-user computing environments should be built around the PASS testing methodology.

END-USER COMPUTING ENVIRONMENTS IT environments continue to evolve and change, making them harder to maintain, manage and control. This is particularly true of end-user computing environments where a number of new trends are taking hold. For example, consumerization of IT is causing the number and type of client devices to explode. End-user devices now include desktops, laptops, thin clients, tablets and smartphones. Windows-only environments are increasingly rare, with additional operating systems such OS X, iOS and Android becoming more popular. Bring-your-own-device (BYOD) initiatives represent another major trend impacting end-user computing environments. While BYOD offers potential benefits such as cost savings and improved productivity, it also introduces new challenges. Users may attach devices with non-standard operating systems, out-of-date patches and little or no security software. Yet IT must still ensure secure and properly functioning IT services. Consumerization and BYOD are already making a significant impact on companies like VMware and Canonical. In late 2011, VMware launched a BYOD program that requires all of its 6,000 U.S. employees to user their own personal smartphones. The company is now working to expand the program to include laptops and desktops. Canonical is another company that embraces consumerization and BYOD. Its remote workers–consisting of 80% of all employees–are responsible for providing their own laptops or desktops for home offices. Even companies without formal BYOD programs are seeing employees connect personal devices to company networks.

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Getting the Performance You Need with VDI and BYOD Overcoming the Challenges of Virtual Desktop Infrastructure (VDI), Desktop-as-a-Service (DaaS) and Bring-Your-Own-Device (BYOD)

Virtualization technologies are also impacting client environments. No longer constrained to servers, virtualization now extends to virtual desktop infrastructure (VDI) and application streaming. Public cloud services are involved here too, with end users accessing an array of applications through software-as-a-service (SaaS) and entire desktops through desktop-as-aservice (DaaS). As these services extend to off-premise data centers, users must access them over wide area networks (WAN). All these trends and technologies are ultimately meant to improve the business, not just make IT more complex. Consumerization and BYOD can increase productivity and job satisfaction as well as lower costs. VDI, DaaS and SaaS can improve speed and agility while also driving efficiency gains. However, in order to meet these objectives, a variety of new challenges must be overcome.

NETWORK CHALLENGES Changes in end-user computing environments can have a profound, and sometimes surprising, impact on the network. Of course the converse is also true. The network has a significant impact on the performance, availability, security and scale of end-user computing environments. Without a properly designed, tested and functioning network, every clientrelated initiative can fail. As employees introduce new devices to the network, whether on their own or through a formal BYOD program, the mix of traffic may change significantly. Even a small increase in video traffic on wired or wireless networks can potentially slow business critical applications running on the same network. High-resolution displays on some consumer devices, such as the iPad with retina display, are extremely bandwidth hungry. The addition of application or desktop virtualization also places strain on the network. To ensure a positive user experience, virtualized applications consume large amounts of bandwidth–potentially impacting the responsiveness of other applications. Since VDI environments depend greatly on shared storage, they often cause performance degradations in storage area networks (SAN). When the SAN slows, a variety of IT services and applications may also be impacted. Symptoms of network problems created by new client technologies may include: • Budget overruns when deploying new client architectures • Excessive performance complaints by users • Additional hardware purchases soon after initial roll out • Availability and reliability issues during peak usage periods • Resistance to new technology adoption Making matters worse, new technologies and new approaches to IT are not adopted in isolation. In fact, many new client technologies are adopted simultaneously or in quick succession. For example, in order to keep applications from running directly on employee devices, BYOD initiatives can lead to application virtualization projects.

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Getting the Performance You Need with VDI and BYOD Overcoming the Challenges of Virtual Desktop Infrastructure (VDI), Desktop-as-a-Service (DaaS) and Bring-Your-Own-Device (BYOD

Similarly, as applications are virtualized and streamed to end-user devices, application virtualization initiatives may be expanded to include entire desktops. Then, to improve the efficiency and performance of both virtualized applications and desktops, back-end infrastructures may be built on private cloud infrastructures or delivered as a service from public cloud environments. For the IT organization to help drive productivity, job satisfaction, efficiency, cost savings and agility, it must ensure that the network can handle all the new traffic patterns. The only way to achieve this is through realistic testing.

REALISTIC NETWORK TESTING To overcome the challenges of modern, end-user computing environments–including VDI, DaaS and BYOD–IT organizations must perform in-depth network testing. The key is to test with realistic workloads and accurately simulate real-world network conditions. This requires test tools that simulate the constantly evolving client devices and protocols, and that are designed to exercise the broad spectrum of client architectures. Protocols and technologies such as FusionFX, HDX, PCoIP, RDP and RCA are commonly used in end-user client environments. They all have a number of technical differences, making some more attractive than others in specific client scenarios. Proper network testing can help reveal whether each protocol is delivering the expected performance, availability, security and scale to the applications they support. The protocols needed to support office applications are quite different from those needed for video conferencing. Realistic network testing also requires a test methodology which maps technical capabilities and test cases to higher-level objectives. Spirent not only offers tools and equipment that support modern client architectures, it has developed a methodology called PASS Testing that enables Performance, Availability, Security and Scale (PASS) objectives to be validated as part of the testing process. The PASS methodology is freely available and comes with detailed procedures and test cases for testing modern client environments.

Benefits of Realistic Network Testing By performing realistic network testing with the PASS methodology – before, during and/or after roll out of new client architectures–a number of benefits can be achieved. With realistic PASS testing you can: • Prepare accurate equipment budgets • Increase end-user satisfaction • Meet targets service level agreements (SLA) without additional hardware purchases • Maintain availability and reliability during peak usage periods • Increase new technology adoption rates

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Business leaders and IT managers must ensure network test teams are properly equipped with both the tools and methodologies required to perform realistic testing of today’s end-user computing environments. Test engineers and others involved directly in network testing for modern end-user environments should continue reading to learn more about the related technologies, specific testing challenges and best practices.

END-USER COMPUTING TECHNOLOGIES While consumerization and BYOD add a variety of new physical devices to end-user computing environments, virtualization and cloud computing introduce a vast array of new architectures and technologies. These include virtual desktop infrastructure (VDI), server-based computing (SBC), desktop-as-a-service (DaaS) and others. Since these approaches to end-user computing have many similarities, their definitions have some overlap. Here are some relatively neutral definitions. However, keep in mind that alternate–and sometimes conflicting– definitions are also used within the industry: • VDI is the practice of hosting a desktop operating system within a virtual machine (VM) in a server and sharing the display back to the client device. • SBC is the practice of hosting and running applications on a server and displaying them to individual clients. • DaaS is third party delivery of VDI services through a subscription model, often using a multi-tenant delivery infrastructure. Examples of specific solutions that use these technologies include: • VDI: Citrix XenDesktop, Microsoft VDI Suites and VMware View • SBC: Citrix XenApp and Microsoft RDS • DaaS: Desktone, dinCloud and Nivio It is also helpful to note that major architectural differences may exist between specific implementations of VDI, SBC and DaaS solutions. For example, server infrastructures used to deliver desktops may be on-premise or off-premise. They may also be virtualized or built with physical resources such as blade servers. Similarly, client-side devices may use virtualization or rely on physical implementations such as thin clients or full desktops.

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Getting the Performance You Need with VDI and BYOD Overcoming the Challenges of Virtual Desktop Infrastructure (VDI), Desktop-as-a-Service (DaaS) and Bring-Your-Own-Device (BYOD

The Impact of Underlying Technologies Beyond the differences in architecture and overall approach for the various end-user computing environments, there are also differences in underlying technologies and protocols. FusionFX, HDX, PCoIP, RDP, RCA and others are used to carry display information to client devices. Yet each one has a unique set of behaviors as well as a distinct impact to the network. While the IT organization doesn’t always have a choice as to which protocol is used, it does have a strong impact on how they perform. Network architects must design networks that meet the requirements of the underlying protocols so they can perform to specification. Similarly, network test teams must test and validate the performance of each end-user environment based in part on which protocols are used. Failure to do any of this may result in periodic or ongoing performance issues, unexpected downtime and other difficult-to-diagnose application errors. Differences in protocol features and capabilities lead to differences in network behavior and therefore have a direct impact on testing. Some protocols work well in LAN environments yet fall short in WAN environments. Some are built on TCP which provides retransmission but also uses aggressive congestion avoidance algorithms which can dramatically impact interface responsiveness. Some are bandwidth intensives while others simply use what is available. Some use compression to reduce bandwidth but can also create performance issues due to increased CPU demand on the server.

TESTING CHALLENGES When it comes to modern end-user computing environments, test tools and strategies must address differences in applications, devices, users and architectures. Applications Different applications have different behaviors that represent different demands on the infrastructure, particularly the network. Testers need tools that accurately determine whether YouTube, Skype and other video-based applications suffer from pauses or poor image quality. They also need to simulate applications such as Adobe Reader which build user views in real time. SaaS and other web-based applications also need solid network validation testing. Devices Test equipment must have the capability to test against real client devices supporting the latest versions of software. It must also enable testing of back-end infrastructure such as that used in VDI environments. This includes determining how many applications or desktops can be supported by each server as well as testing the capacity of shared storage environments such as SANs. It may also include testing WAN environments, including WAN accelerators and compression capabilities.

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Getting the Performance You Need with VDI and BYOD Overcoming the Challenges of Virtual Desktop Infrastructure (VDI), Desktop-as-a-Service (DaaS) and Bring-Your-Own-Device (BYOD)

Users When it comes to simulating users, test equipment must be able to drive full users with realistic behavior patterns. This is not just about testing how many users can open Outlook at a time, especially since not all users log on and load Outlook at exactly the same time. It is about statistically accurate usage behaviors for individual users and groups of users at different times of day and across a range of applications. Architectural Artifacts Test tools must also have the ability to test the network scenarios that are specifically related to certain client architectures. Some VDI architectures must handle boot storms, where large numbers of users simultaneously boot their virtual desktops. Others rely on high-performance shared storage environments that demand testing of ISCSI, FCOE and solid state disk (SSD) performance. Some VDI implementations–such as the one Piston Cloud added to the OpenStack cloud platform–need to be tested while running in a private cloud infrastructure.

REALISTIC TESTING WITH PASS METHODOLOGY To ensure higher-level objectives such as SLAs are met, realistic network testing of modern enduser computing environments should be built around the PASS testing methodology. Example test scenarios for each element of PASS are shown below: Performance • Boot storms impacting the LAN for on-site employees, the WAN for branch office and remote workers, as well as servers, memory, SAN and storage arrays for all • Network congestion in WIFI, LAN, WAN and data center networks and impact on bandwidth, latency and frame loss Availability • Resiliency of different protocols with various types of WAN impairments–for example, impact on number of supported users if more compression is required for a slow WAN • Distance from data center at which point office or other applications become unusable Security • Impact of encryption, SSL and IPSec VPN on clients and servers with high user count • Ability of application-aware firewalls to recognize all the protocols and keep up to date with latest versions under high-bandwidth usage conditions Scale • Maximum number of users supported with statistically balanced usage and resource consumption patterns • Number of users that can maintain high experience levels during periods of peak demand

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Getting the Performance You Need with VDI and BYOD Overcoming the Challenges of Virtual Desktop Infrastructure (VDI), Desktop-as-a-Service (DaaS) and Bring-Your-Own-Device (BYOD

CONCLUSION End-user computing environments are evolving once again. Trends like consumerization and BYOD are driving a major increase in the number and type of devices connecting to company networks. At the same time, virtualization and cloud computing technologies used in end-user computing environments are placing new and often unexpected strain on WIFI, LAN, WAN and data center networks. Without realistic network testing, IT organizations will fail to achieve the benefits promised by VDI, DaaS and other modern end-user computing architectures. Realistic network testing involves accurately simulating statistically correct user loads, including both individuals and groups, while using real clients with the latest version of protocols. Successful testing also requires strategies as well as test tools that understand and address the many differences in applications, devices, users and architectures. Finally, to ensure higherlevel objectives such as SLAs are met, realistic network testing of modern end-user computing environments should be built around the PASS testing methodology.

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