xendesktop to branch offices

8/4/2019 XenDesktop to Branch Offices

1/30

WHITE PAPER | Citrix XenDesktop and Branch Repeater

www.citrix.com

Performance Assessment andBandwidth Analysis for DeliveringXenDesktop to Branch Offices

Citrix XenDesktop and Branch Repeater Performance Analysis


2/30

Page 2

Contents

Executive Overview ..........................................................................................................................................

Product Overview ..............................................................................................................................................

Test Environment ..............................................................................................................................................

Test Methodology ..............................................................................................................................................

Performance Results and Analysis ................................................................................................................ 12

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

Appendix A - Hardware and Software Configurations .............................................................................. 25

Appendix B - Citrix XenDesktop Configurations ...................................................................................... 26

Appendix C Citrix Branch Repeater Configurations .............................................................................. 27

Appendix D Login VSI Pro Configurations ............................................................................................ 27

Appendix E HDX MediaStream Active Directory GPOs ..................................................................... 28

Appendix F - References ................................................................................................................................28


3/30

Page 3

Executive Overview

Desktop virtualization is rapidly gaining momentum in the IT industry. The desire to centralize andsecure desktops, applications, and corporate data is a driving factor behind this trend. To make thetransition to a virtual desktop platform CIOs and administrators alike must ensure that all users havea positive experience with the virtual desktop, even if they work in remote branch offices away fromthe corporate datacenter. This whitepaper details the network bandwidth requirements per user fora variety of use cases and provides the IT professional with critical data to plan the delivery of Citrix

virtual desktops across a WAN.

To provide users with a positive virtual desktop experience, IT professionals must ensure anacceptable level of desktop performance can be provided to both corporate users as well as thebranch office users. The purpose of this paper is to provide the network administrator withguidance for determining the amount of available bandwidth required for a Citrix XenDesktopsolution based on popular use cases. This paper details how the introduction of Citrix BranchRepeater can provide significant bandwidth savings and performance improvements for branchoffice users and can in some cases negate the need for a costly network upgrade.

This unique partnership of combining Citrix XenDesktop with Branch Repeater is the only solutionon the market where the ability to compress native XenDesktop traffic is transitioned to a WANoptimization solution, Citrix Branch Repeater, for optimal virtual desktop performance. Theadaptive orchestration where XenDesktop becomes Branch Repeater-aware provides significantsavings in the overall bandwidth requirements for XenDesktop as shown throughout this report.

The Citrix Consulting Solutions team conducted all the testing represented in this paper within the

Consulting lab environment at Citrix headquarters. All tests were based on the widely acceptedLoginVSI methodology and focused on common workflows such as standard MS Office tasks,internet browsing, printing, and video.

Table 1 represents a high level overview of the bandwidth requirements for standard virtual desktop workflows as represented in this document. The Branch Repeater numbers displayed in the tablerepresent a warm run (the test data passed through the Branch Repeater prior to testing). When datafirst passes through Branch Repeater, compression algorithms are utilized to optimize TCP trafficand cache the data stream. During the second request for the same data, Branch Repeater utilizes atokenizing engine to serve recognized data streams from local cache rather than pulling the samedata stream across the WAN. Therefore, the greatest bandwidth savings is recognized in all datatransfers after the first pass as shown in the following table.


4/30

Page 4

Workflow Avg UserLoad

Environment Avg BandwidthConsumed

Office 20 Native XenDesktop 43 kbpsXenDesktop & Branch Repeater 31 kbps

Internet Browsing 10-12 Native XenDesktop 85 kbps

XenDesktop & Branch Repeater 38 kbpsPrinting 1 (5MB MS Word & PDF) 1

Native XenDesktop 553-593 kbpsXenDesktop & Branch Repeater 155-180 kbps

Flash Video(server-rendered) 5

Native XenDesktop 174 kbpsXenDesktop & Branch Repeater 128 kbps

Standard WMV Video(client-rendered) 4


High Definition WMV Video 2 (client-rendered) 1-2


Table 1: Average Bandwidth per Session

The Citrix Branch Repeater plays a critical role in optimizing an existing WAN connection andimproving the overall virtual desktop user experience in the branch office. The following key findings from this report emphasize the strategic cost savings and performance improvement aBranch Repeater solution can provide for any branch office XenDesktop deployment.

Citrix Branch Repeater can reduce the overall average bandwidth consumed per session by up to 89% .

Citrix Branch Repeater can reduce the amount of time it takes for a XenDesktop session tolaunch on a congested WAN connection by up to 40% .

Citrix Branch Repeater can double the number of users able to execute similar virtualdesktop activities on the same congested WAN connection.

Citrix Branch Repeater can reduce the amount of time it takes for the print request to spoolfrom the virtual desktop to the branch office print server by up to 60% .

1 To assess the maximum amount of bandwidth consumed for a single print job only one document was printedper test on an uncongested WAN to provide the most conservative guidance. Additional XenDesktop policies andBranch Repeater priority queuing can be implemented to optimize bandwidth availability during print jobs.2 The WAN parameters for the HD video were increased to 10mbps given that the data rate of the High Definitionvideo was 6.5 mbps. Only 1 user was evaluated on the 10mbps for native XenDesktop, but 2 users were evaluatedfor XenDesktop with Branch Repeater.


5/30

Page 5

Product Overview

Citrix XenDesktop

Citrix XenDesktop is a desktop virtualization solution that delivers Windows desktops as an on-demand service to any user, anywhere. With FlexCast delivery technology, XenDesktop canquickly and securely deliver individual applications or complete desktops to the entire enterprise,

whether they are task workers, knowledge workers or mobile workers. Users now have the flexibility to access their desktop on any device, anytime, with a high-definition user experience. WithXenDesktop, IT can manage single instances of each OS, application and user profile anddynamically assemble them to increase business agility and greatly simplify desktop management.XenDesktops open architecture enables customers to easily adopt desktop virtualization using any hypervisor, storage or management infrastructure.

Citrix Branch Repeater

Citrix Branch Repeater is a branch optimization solution that accelerates and simplifies branchinfrastructure. Branch Repeater solutions reduce IT costs and increase user productivity by simplifying branch startup and management, and providing users the best access experience.

The Branch Repeater products achieve WAN optimization by combining a variety of technologies:

TCP Optimization: Branch Repeater is a symmetric solution, where a Branch Repeater islocated at each end of the WAN connection (in the datacenter and in the branch office)recognize each others presence and employ RFC compliant TCP optimization techniquesthat ensure optimal utilization of the network bandwidth.

Traffic Prioritization (QoS): Administrators can classify network bandwidth based on TCPport numbers and IP ranges to prioritize the delivery of TCP segments based on theclassification. Furthermore, Branch Repeater recognizes the priorities of the various ICA

virtual channels and can ensure preferential treatment of real-time critical data such as audio.

Compression: Branch Repeater can detect repeating patterns in the transmitted data andutilize very small tokens across the WAN to identify such repeating data patterns and servethe data to the user out of the appliance memory; therefore, restricting the amount of datarequired to traverse the WAN and improving user experience.

Protocol Optimization: Branch Repeater can optimize a variety of common applicationprotocols. Citrix XenDesktop leverages the ICA protocol, which employs a variety of optimization and security features natively. In order to apply compression, a WAN optimizermust be able to decrypt the ICA workload, identify repeating patterns within the ICA virtualchannels, apply the optimization, and re-encrypt the data stream. This is why Citrix BranchRepeater is the only WAN optimization product capable of directly optimizing the ICApayloads on the protocol level.


6/30

Page 6

This paper focuses on the virtual desktop acceleration gained from the joint deployment of CitrixRepeater in the datacenter and Citrix Branch Repeater in the remote branch office.

Citrix High Definition User Experience

With the release of Citrix XenDesktop 4, Citrix committed to providing the best high definition userexperience through the introduction of HDX technology. Citrix HDX technology builds onexisting Citrix user experience innovations from the datacenter to the device, adding enhancementsfor multimedia, voice, video and 3D graphics. Citrix HDX is comprised the following categories:

HDX Broadcast Ensures high-performance of virtual desktops and applications over any network, including high-latency and low-bandwidth environments.

HDX WAN Optimization Optimizes performance by utilizing Citix Branch Repeater tocache bandwidth intensive data and graphics and deliver them from the most efficientlocation.

HDX MediaStream Accelerates multimedia performance through compression or, whenpossible, redirection and client-side rendering.

HDX RealTime Enhances real-time voice and video using advanced encoding andstreaming to ensure a no compromise end-user experience.

HDX 3D Optimizes the performance of everything from graphics-intensive 2Denvironments to advanced 3D geospatial applications using software and hardware basedrendering in the datacenter and on the device.

HDX Plug-n-Play Enables simple connectivity for all local devices in a virtualizedenvironment, including USB, multi-monitor, printers and peripherals.

Citrix XenServer

Citrix XenServer is open, powerful server virtualization that radically reduces datacenter costs by transforming static and complex datacenter environments into more dynamic, easy-to-manage server

workload delivery centers. Based on the open source Xen hypervisor, XenServer delivers a secureand mature server virtualization platform with near bare-metal performance.

Login VSI 2.1 Pro (Benchmarking Tool)Login VSI 2.1 is a benchmarking tool specifically designed for SBC and VDI environments. VSIloads the system with simulated user workload, and focuses on how much user load can begenerated within the system before performance degrades. VSI is a completely platform andprotocol independent tool. The VSI implementation and configuration is very simple and providesengineers and administrators with a turn-key benchmark solution that allows testers to gathermetrics in days versus weeks. The tool is available in two versions. The free version is configured

with a standard user workflow that executes a combination of Microsoft Office, Internet Explorer


7/30

Page 7

and printing tasks. The VSI Pro (paid version) provides testers the ability to generate workloads that vary in intensity as well as the ability to execute custom workflows.

Login Consultants was the first company worldwide to be appointed as a Citrix ManagedConsultancy Provider. The strategic relationship between Citrix and Login Consultants has

developed XenDesktop testing standards that are proven and repeatable in any customerenvironment.

Test Environment

The Citrix Consulting Solutions team is committed to architecting and implementing real-world testenvironments based on prior Citrix Consulting customer engagements. The following testenvironment was constructed within the Consulting Solutions lab in Fort Lauderdale, Florida toemulate a branch office scenario where end users are connecting to their virtual desktop over adedicated WAN link. The test environment consisted of a datacenter environment with Citrix

Repeater and a remote branch office environment with Citrix Branch Repeater connected by asimulated WAN. All XenDesktop, infrastructure, and branch office machines were virtualized using Citrix XenServer.

T E C H N O L O G I E S

M GM T L AN A L AN BCONSOLE

LINKTROPY MINI

P O W E R S T A T U S

Figure 1: Performance Assessment and Bandwidth Analysis Environment Architecture

The Citrix Consulting Solutions team leveraged Login VSI 2.0 Pro to create a standard method forlaunching simultaneous virtual desktops through XenDesktop and a standard process for executing


8/30

Page 8

automated end user workflows that incorporated applications such as Microsoft Office 2007 andInternet Explorer 7 web browsing. Although the number of users and workflows varied, thefollowing steps provide a high level overview of the test execution process utilizing Login VSI 2.0Pro:

Login VSI 2.0 Pro supports multiple simultaneous launchers through a master and slaveconfiguration. To execute a test, the Login VSI 2.0 Pro console on the master launcher isconfigured with desktop connection information and a UNC path to the Login VSI share.

The Login VSI share must be on a file server that is accessible to both the launcher and the virtual desktop executing the end user workflow.

The Login VSI share contains four critical files: VSILauncher.ini, VSITarget.ini,LoginVSI.csv and LoginVSI.lic. The VSILauncher.ini file provides criteria regarding connection information for accessing the Delivery Controller and launcher information suchas the list of additional launchers acting as slaves. The VSITarget.ini file is configurable in

the Pro version only to support light, medium, heavy or custom workflows. TheLoginVSI.csv file contains a list of unique usernames and passwords. The LoginVSI.liclicense file is necessary for the Pro version of the tool.

To execute a test, the custom connection method is leveraged and a custom Python script which emulates Internet Explorer browser sessions is used to launch multiple Web Interfacesessions.

The Python script is also leveraged to automatically enter multiple test user credentials oneach Web Interface session launched. These credentials are stored in the specifiedLoginVSI.csv file.

Each Launcher had the Citrix Online Plug-in installed locally prior to test execution.

After the user was authenticated, the virtual desktop was automatically launched. The Login VSI Launcher completed the process of launching desktop connections at this point.

The standard vDisk used for each virtual desktop was preconfigured with Microsoft Office2007, RealTime Player, Windows Media Player and the Login VSI target deploymentsoftware. Users were granted administrative privileges (as part of the Login VSI installation)and all the workflow scripts were tested to ensure that all pop-up warnings were removed.

The Login VSI component on the virtual desktop referenced the VSITarget.ini file on the VSI share. The VSITarget.ini file provided the component with instructions regarding theuser workflow.

The user workflow was embedded within the local desktop. All the keystrokes and mouseclicks that are executed during the workflow are scripted within the virtual desktop;therefore, there are no keystrokes or mouse clicks from the launcher in the branch officetraversing the WAN to communicate with the XenDesktop virtual desktop.


9/30

Page 9

Test Methodology

The project had two objectives. The first objective was to determine the average amount of bandwidth required for a XenDesktop virtual desktop accessed from a branch office. The secondobjective was to measure the performance improvement that a Citrix Branch Repeater solution canprovide to the branch office environment when using XenDesktop. The testing methodology wasdesigned to assess both of these key objectives under varying user workflows and to provideguidance to the customer community regarding bandwidth requirements for a branch office CitrixXenDesktop deployment without a Citrix Branch Repeater solution and the performanceimprovements gained from incorporating a Citrix Branch Repeater in a XenDesktop solution.Given that user activities can vary throughout the work day, the test methodology separated enduser tasks into four main categories: Microsoft Office, Internet Explorer, Printing, and Videoactivities.

In an effort to minimize the variables associated with the testing, a single WAN connection wasselected between the branch office and the datacenter hosting the virtual desktops. It wasdetermined that an intra-continental T1 connection would resemble a large portion of the usercommunity looking to implement XenDesktop in a branch office and the bandwidth numbersprovided in this document can be used as guidance for determining the correct WAN connectiontype for any remote office. The WAN parameters select were based on a more restrictive WANconnection to provide conservative guidance. For the purpose of the testing reflected in thisdocument, the following WAN parameters were configured utilizing an Apposite Linktropy WANemulator:

Data

ThroughputLatency Packet Loss

1.5 Mbps 80ms 1%

Table 2: Test Environment WAN Connection

Microsoft Office 2007 Workflow

The Login VSI tool provides a standard medium user load workflow that incorporates Office,Solidata PDF writer with Adobe Reader, and Internet Explorer. For the purpose of this Officespecific workflow, the default Login VSI workflow was edited to only execute the Office portion of

the overall standard medium workflow. Login VSI workflows for Office are configured torandomize the content for each user. The Office content accessed and modified during the

workflow execution is derived from a randomized pool of files to ensure that the users are executing different activities. The Login VSI Office workflow is strategic to the Branch Repeater aspect of this testing because unlike the other workflows, the Office content executed with the Login VSI

workflow is uniquely different for each user. By having each user access different emails andPowerPoint presentations, the data gathered from the Office workflow most closely resembles areal-world customer environment.


10/30

Page 10

To execute the Office workflow, the user load was incremented in user counts of five for each testcycle. The launcher was configured with a 30-second interval between each user launch. During each test cycle, a single virtual desktop was monitored by the Consulting team to determine theoverall performance and responsiveness of the environment. This subjective assessment was madeby evaluating the responsiveness to typing, mouse clicks, and screen refreshes during each test cycle.

Several metrics were measured in addition to the overall user experience. The average bandwidthconsumed for the workflow was evaluated with and without Branch Repeater. In order to have allthe necessary users online at the same time to gather these metrics, the workflow would loopcontinuously to allow the WAN emulator to record all active sessions during the same 10-minutetime interval given that there was a 30-second window between user launches. For example, toassess 10 users in the environment the overall workflow would execute for 15 minutes to allow all10 users to be active for 10 minutes to get a true average of bandwidth consumed. Additionalmetrics such as XenDesktop launch time and Branch Repeater compression ratios were alsogathered for this workflow. It should be noted that the Branch Repeater numbers represented in

this testing reflect a warm run. A warm run is when the Branch Repeater has executed the Office workflow prior to the test cycle starting. With a warm run not all documents are seen prior to thestart of the workflow since the content varies from user to user.

Internet Explorer Workflow

The Consulting team developed a customized Internet Explorer workflow that accesses thefollowing websites: Citrix.com, Yahoo Finance, MSN, Gap.com, Amazon.com, Google Maps andCNN. The customized workflow is over 11 minutes in duration. The Login VSI launcher was usedin conjunction with the customized workflow to bring users online in the same 30-second launch

interval used by the Office workflow scenario. Given that the workflow was only 11 minutes induration, the workflow continued to loop for each user to allow all users to be active for a 10-minute window for measurements purposes. It should be mentioned that the websites specified inthe Internet Explorer workflow did include stock tickers and rotating ads, but the overall content

was similar in nature for every user added to the environment.

The execution of this workflow was comparable in design to the Office workflow, so only themetrics specific to the Internet Explorer component of these workflows were collected. The overalluser experience was monitored in the same fashion as the Office workflow. A single virtual desktop

was monitored by the Consulting team to determine the overall performance and responsiveness of the environment. This subjective assessment was made by evaluating the responsiveness to typing,mouse clicks, and screen refreshes during each test cycle. The additional metrics gathered specific tothe Internet Explorer workflow included average bandwidth consumed and Branch Repeatercompression ratios. It should be noted that the Branch Repeater numbers represented in theInternet Explorer workflow reflect a warm run.


11/30

Page 11

Printing Workflow

Unlike the previous two workflows where the user continuously interacts with the desktop, a printjob is a single request from the virtual desktop to the printer. To assess the printing performancefor a variety of applications, a single user printed a 5MB Microsoft Word document and a 5MB PDF

file from within the virtual XenDesktop environment. The print server was located in the branchoffice which required the virtual desktop to spool the print request across the WAN. CitrixXenDesktop does support the same printer policies that Citrix XenApp provides. By default, CitrixXenDesktop polices are configured to set print spool requests as a low priority. For moreinformation regarding the XenDesktop policies used in this testing, please reference the Appendix Aof this document

For the Printing workflows, key metrics such as print spooling execution time, total bandwidthconsumed, and Branch Repeater compression ratios were gathered. It should be noted that theBranch Repeater numbers represented in the printing workflow reflect a warm run.

Video Workflow

One of the strategic differences with XenDesktop versus competitive products is the HDX technologies. When possible, HDX MediaStream leverages the processing power of the endpointdevice to render multimedia content. The video workflow assessed the performance of Windows

video utilizing the HDX MediaStream for Windows technology and Flash video utilizing standardserver-side video rendering.

HDX MediaStream for Windows

HDX MediaStream with Windows is a very powerful technology for a branch office virtual desktopdeployment. HDX MediaStream leverages the processing power of the branch office end-userdevice to render the multimedia content. This allows the video stream to be sent to the branchoffice in its native format, which typically requires much less bandwidth than rendering the video

within the virtual desktop, and sending all the individual frames across the WAN. For the purposeof the testing in this paper, the process of obtaining the Windows Media content and rendering the

Windows Media content was divided between the virtual desktop running in the datacenter and theend user device running in the branch office. The virtual desktop was responsible for fetching thecontent from a file server in the datacenter that could only be accessed by the virtual desktop. The

virtual desktop fetched the WMV file from the file server and sent the content to the branch office

device in its native format. Once the branch office device received the content, the device utilizedits local Windows Media Player to render the video content; therefore, the video appears in the

virtual desktop with the same quality as rendering the video on the local device. Windows MediaPlayer was used to render the videos in this testing, but other media players based on DirectShow,DMO or Media Foundation could also be used

In this test scenario, the server-side fetching and client-side rendering of two Windows Media Videos were monitored. The first WMV file was a 5MB video, six minutes in duration with a datarate of 70kbps, frame rate of 15 frames/second, and a 320x252 display. This 5MB video was


12/30

Page 12

considered to be a standard video. The second video was labeled as a high definition (HD) video. The HD video was the robotica.wmv file downloadable from the Microsoft WMV HD ConentShowcase website. The HD video was a 16MB video, twenty-one seconds in duration with a datarate of 6500kbps, frame rate of 23 frames/second, and a 1280x720 display.

For each video test scenario the video duration was a key component in evaluating the overallbandwidth for one to four users. In this scenario the video was executed concurrently across allsessions without a 30-second launch interval as documented for the other workflows. The overalluser experience was evaluated based on the screen refreshes and overall video appearance. Otherkey metrics included the total bandwidth consumed and the time duration for the data transfer. Itshould be noted that the Branch Repeater numbers represented in the HDX MediaStream workflow reflect a warm run.

Flash Video

When Flash video is viewed across the WAN, XenDesktop utilizes server-side fetching and server-side rendering for the Flash video. With server-side fetching and server-side rendering, the Flash

video is rendered within the virtual desktop in the datacenter and the screen updates are sent acrossthe WAN connection.

For each test scenario, the Flash video was a 39MB flash video that was forty-one minutes, with adata rate of 66.5kbps, frame rate of 9.9 frames/second, and a 320x240 display. The ShockwaveFlash video player was installed on the virtual desktop. The test scenarios included both a single user and a five-user test. The five-user test leveraged the VSI launcher where users had a 30-secondinterval between session launches. The video ran for fifteen minutes to gather metrics for a ten-minute average after all five users were actively watching the video. For this testing the overall userexperience was evaluated based on the screen refreshes and overall video appearance. Other key metrics included the average bandwidth consumed. It should also be mentioned that the BranchRepeater numbers represented in this testing reflect a warm run.

Performance Results and Analysis

Microsoft Office 2007 Workflows

Microsoft Office is the most frequently virtualized application utilizing Citrix technology. Figure 2shows the average bandwidth consumed per user across the WAN as users performing Office

workflow were added to the environment and Figure 3 shows total average bandwidth consumedfor all users across the WAN.


13/30

Page 13

Figure 2: Office Workflow-Average Bandwidth Consumed per User

Average Bandwidth consumed per User

XenDesktop uses the ICA protocol to render the virtual desktop on the end user device. The ICAprotocol is a highly optimized protocol by design. The ICA protocol will consume as muchavailable bandwidth as possible on a given link as noted by the higher bandwidth consumed during low user load. When the amount of available bandwidth is restricted, the ICA protocol performs

well until the bandwidth restriction becomes too severe and user performance is degraded. Thisaspect of the protocol made it important to also monitor user performance of the virtual desktopexecuting the Office workflow.

In the Average Bandwidth Consumed per User graph, the average bandwidth consumed line flattensas the number of users continues to increase. The objective of this testing was not to determine theminimum amount of bandwidth required, instead the objective was to identify the average amountof bandwidth required to provide a user experience parallel to that of the local desktop. Figure 2shows that the average bandwidth consumed per user required for the Office workflow for nativeXenDesktop is effectively 43 kbps.

As part of the improvements in XenDesktop 4 and Branch Repeater 5, Branch Repeater can now accelerate the delivery of desktops by letting XenDesktop detect when Branch Repeaters are activein the environment. Branch Repeater will recognize and parse the incoming ICA stream and takepart in the initial connection negotiations. Once the Citrix Online Plug-in and Delivery Controllerare aware of the Branch Repeaters, they will disable their native ICA compressors and hand-off thecompression to the Branch Repeaters.

0.00

10.00

20.00

30.00

40.00

50.00

60.00

0 5 10 15 20 25 A v g B a n d w i d t h C o n s u m e d

p e r U s e r

( k b p s )

Users

Office Workflow

XenDesktop Average Bandwidth per User (Native)

XenDesktop Average Bandwidth per User (with Branch Repeater)


14/30

Page 14

When the Branch Repeater was introduced into the environment, the average bandwidth per userrequired for the Office workflow was reduced by 28% to 31 kbps while maintaining an excellentoverall user experience.

Figure 3: Office Workflow-Bandwidth Consumed for All Users

Bandwidth Consumed for All Users

One of the key benefits of introducing a Branch Repeater into any branch office scenario is the

ability to add more users to the existing environment without upgrading the WAN connection. When reviewing the total bandwidth consumed for all users, it can be derived that total bandwidthconsumed for 20 users was approximately 861 kbps for native XenDesktop and 622 kbps withBranch Repeater. Given that a Branch Repeater user consumes an average of 31 kbps, then 7.7additional users could be added to the environment to reach the same level of WAN utilizationshown without a Branch Repeater; therefore, approximately 40% more users can be added to aXenDesktop Office workflow environment with a Branch Repeater solution in place.

0100200300400500600700800900

1000

0 5 10 15 20 25

A v g B a n d w i d t h C o n s u m e d

( k b p s )

Users

Office Workflow

XenDesktop Average Bandwidth (Native)

XenDesktop Average Bandwidth (with Branch Repeater)


15/30

Page 15

Figure 4: Office Workflow-XenDesktop Launch Time

XenDesktop Launch Time

There is an inherent amount of time between the user entering their credentials into Web Interfaceand the appearance of the virtual desktop display on the users screen. During this period, thefollowing actions take place:

Web Interface passes the validated credentials to the Delivery Controller XML Service

The XML Service authenticates the user against Active Directory

The XML Service then determines which virtual desktops are available to that user

The available desktop information is sent to Web Interface

Web Interface presents the desktop information to the user device

Web Interface creates an ICA file for user device

The Citrix Online Plug-in on the user device establishes the ICA connection over the WANto the desktop

In this test environment, the average XenDesktop launch time took approximately 6 seconds(Figure 4 displays the logon times as collected during the testing cycle). When WAN trafficconsumed more than 60% of the overall available bandwidth, the launch time increased toapproximately 10 seconds. When a Citrix Branch Repeater is introduced into the congestedenvironment, the launch time of the XenDesktop session returned to the original 6 seconds,providing up to 40% XenDesktop Session Launch time improvements.

0 5 10 15

XenDesktop Launch Time with BranchRepeater Low WAN Congestion

Native XenDesktop Launch Time Low WANCongestion

XenDesktop Launch Time with BranchRepeater High WAN Congestion

Native XenDesktop Launch Time High WANCongestion

Seconds

XenDesktop Launch Time


16/30

Page 16

Internet Explorer Workflows

Internet Explorer browsing through a virtual desktop can be more bandwidth intensive than Office.Figures 5 and 6 show the average bandwidth consumed per user across the WAN as users are addedto the environment and the total bandwidth consumed across the WAN for all users executing the

Internet Explorer workflow respectively.

Figure 5: Internet Explorer Workflow-Average Bandwidth Consumed per User

Average Bandwidth Consumed per User

In the Average Bandwidth Consumed per User graph, the average bandwidth consumed line flattensas the number of users continues to increase. The Internet Explorer workflow was more bandwidthintensive than the Office workflow and the end user experience began to degrade around 12 users.

Therefore, the average bandwidth per user required for the Internet Explorer workflow for nativeXenDesktop was extracted from the 10-12 user range and is approximately 85 kbps per user. When

the Branch Repeater was introduced into the environment, the average bandwidth per user requiredfor the Internet Explorer workflow was reduced by 55% to a more WAN-friendly 38 kbps per user while maintaining an excellent user experience overall.

0.00

20.00

40.00

60.00

80.00

100.00

120.00

0 2 4 6 8 10 12 14 16

A v g B a n d w i d t h C o n s u m e d

p e r U s e r

( k b p s )

Users


XenDesktop Average Bandwidth per User (Native)

XenDesktop Average Bandwidth per User (with Branch Repeater)


17/30

Page 17

Figure 6: Internet Explorer Workflow-Bandwidth Consumed for All Users

Bandwidth Consumed for All Users

When reviewing the Bandwidth Consumed for All Users graph, the data indicates that total averagebandwidth in the 10-12 user range is approximately 900 kbps for native XenDesktop and 425 kbps

with Branch Repeater. Given that a Branch Repeater user consumes only 38 kbps, then 12.5additional users could be added to the environment to reach the same level of WAN utilizationshown without a Branch Repeater. In other words, the user count supported across a WAN link canbe doubled for Internet Explorer based workflows when a Branch Repeater solution is in place.

Printing Workflows

Figures 7 and 8 show the performance data for printing both a Microsoft Word and PDF documentinstalled on the local desktop to a printer in the remote branch office for a single user.

0

200

400

600

800

1000

1200

1400

0 2 4 6 8 10 12 14 16

A v g D a t a B a n d w i d t h

( k b p s )

Users


XenDesktop Average Bandwidth (Native)

XenDesktop Average Bandwidth (with Branch Repeater)


18/30

Page 18

Figure 7: Printing Workflow-Total Bandwidth per Print Job

Total Bandwidth

The protocol acceleration benefits of Branch Repeater are very pronounced in a data transfersituation such as the print workflow. The Total Bandwidth per Print Job graph shows that with aBranch Repeater solution the data transfer is reduced by 84% for the 5MB Word document and by 89% for the 5MB PDF document.

Figure 8: Printing Workflow-Average Bandwidth Consumed per Document

0 500 1000 1500 2000 2500

5MB PDF NativeXenDesktop

5MB Word NativeXenDesktop

5MB Word XenDesktopwith Branch Repeater

5MB PDF XenDesktopwith Branch Repeater

Total Bandwidth (KB)

Printing Workflow

0 100 200 300 400 500 600 700

5MB Word Native XenDesktop

5MB PDF Native XenDesktop

5MB Word XenDesktop with BranchRepeater

5MB PDF XenDesktop with BranchRepeater

Avg Bandwidth (kbps)

Printing Workflow


19/30

Page 19

Average Bandwidth Consumed per Document

Determining the average bandwidth consumed per user is difficult given the variation in content andfile size for a larger number of users. Instead, the Consulting team recommends determining guidance for the average bandwidth consumed per document. Once the guidance for document

bandwidth requirements is determined, the end user print behaviors must be identified. Thefollowing numbers represent a single user executing a print job on a T1 with all bandwidth availablefor the single print request (maximum bandwidth consumed). Please note that the results will bedifferent on a congested WAN.

Document Average Bandwidth(kbps)

Time to SpoolPrint Job(seconds)

NativeXenDesktop

5MB Word 593 kbps 28s

5MB PDF 533 kbps 31s

XenDesktop withBranch Repeater

5MB Word 180 kbps 15s

5MB PDF 155 kbps 12s

Table 3: Printing Workflow

If the branch office user community does a significant amount of printing, then the Consulting teamrecommends utilizing the XenDesktop policies to configure session limits on the amount of bandwidth a print job can consume. There will be a time trade-off for implementing theXenDesktop policy, but the end user experience in the virtual desktop will not be as impacted whena large print job is spooling over the WAN. When a Branch Repeater is configured in theenvironment, then the Consulting team recommends configuring the Branch Repeater to prioritizeprint traffic relative to other (ICA and non-ICA) traffic, rather than just limiting the bandwidth to aset amount for printing. With Branch Repeater traffic prioritization (QoS), the Branch Repeater canprioritize the accelerated traffic to ensure that all available bandwidth is consumed.

Video Workflows

The video workflows were separated into three distinct: HDX MediaStream for Standard WindowsMedia Video, HDX MediaStream for High Definition Windows Media Video, and Flash Video

(Server-side Rendering).


20/30

Page 20

Figure 9: Video Workflow-Average Bandwidth Consumed per User

Flash Video (Server-side Rendering)

The WAN connection selected for the test data shown throughout this document was configuredfor 80ms latency roundtrip. (HDX MediaStream for Flash can render Flash content on the userdevice, thereby increasing server scalability, only if the connection latency is below 30ms roundtrip.)For all the testing in this document, the latency was configured to 80ms roundtrip, this then forcedXenDesktop to render the Flash video server-side. (QuickTime and Silverlight videos are similarly rendered server-side.)

As Figure 9 shows, the benefits of introducing a Branch Repeater into a server-side rendered videoprovides an average bandwidth consumed savings of approximately 25%. The average bandwidthconsumed for native XenDesktop rendering server-side was 174 kbps while the average bandwidthconsumed with Branch Repeater was 128 kbps.

0 50 100 150 200

MediaStream for Flash NativeXenDesktop

MediaStream for Flash for XenDesktop

with Branch Repeater

Avg Bandwidth per User (kbps)

Video Workflow - Flash


21/30

Page 21

Figure 10: Video Workflow-Average Bandwidth Consumed per Video

HDX MediaStream for Standard WMV

The Standard WMV file was fetched on the server-side and rendered on the client utilizing the HDX MediaStream technology. This configuration allows the video to be sent to the end-user device in itscompact native format versus sending frame updates as represented in the Flash video results.

When the WMV file is sent to the client for rendering, the data transfer time of that WMV file doesnot continue for the entire duration of the video. For example, in this test the total data transfertime of the standard WMV file for native XenDesktop was approximately 400 seconds. When the

video was played, there was an original spike in data transfer at the start of the video varying between 30 to 100 seconds based on the number of videos actively playing (a maximum of foursimultaneous videos were played for this test). Then the data transfer drops off and the ratebecomes very marginal. The graph in Figure 10 only shows the average bandwidth consumedduring the intial data spike.

When the Branch Repeater is introduced into the environment, the spike in data transfer time wasreduced by the amount of data transferred during the spike and the duration the spike appeared.

The bandwidth consumption for this standard WMV file with Branch Repeater spiked in the first 10to 30 seconds and then remained below 10 kbps for the remainder of time the video played. Theaverage bandwidth consumed for the WMV file with native XenDesktop was approximately 464kbps during the data spike; whereas, the average bandwidth consumed for the WMV file withBranch Repeater was approximately 148 kbps, a reduction of 68%. The average bandwidthmeasurements only focused on the data spike timeframe rather than the entire video play time toprovide a better representation of the actual data transfer rate required.

0 200 400 600

MediaStream for Native XenDesktop

MediaStream for XenDesktop withBranch Repeater

Avg Bandwidth per Video (kbps)

Video Workflow - Standard WMV


22/30

Page 22

Figure 11: Video Workflow-Average Bandwidth Consumed per Video

HDX MediaStream for High Definition WMV

The High Definition WMV file required more bandwidth than the standard T1 connection used forall other test scenarios to transfer the data to the user device for rendering. To provide the bestpossible bandwidth guidance for a High Definition video, it was determined that the WANconnection would be increased from 1.5 mbps to 10 mbps for the HD video testing to ensure thatthe effective amount of available bandwidth was greater than the 6.5mbps data rate of the video.

The latency and the packet loss were still consistent with 80ms roundtrip latency and 1% packet loss. The HD video was fetched on the server-side and rendered on the client. This configuration allowsthe video to be sent to the end-user device in its native format versus sending frame updates.

If the remote user had a connection lower than the default threshold of 524kbps for client siderendering of HDX MediaStream for Windows or was unable to utilize the local client resources for

video rendering, then the HD video would render within the virtual desktop on the server and sendindividual frames across the WAN connection to ensure that the user could still see the video andaccess the virtual desktop although the quality would be degraded.

Unlike the standard video, the data transfer was high for the entire duration of the video. Only when the Branch Repeater was introduced into the environment did the data transfer spiked at the

beginning of the video and then remainded marginal for the remainder of time that the video played. This is mentioned because the average bandwidth consumed for the HD WMV file with nativeXenDesktop was approximately 1812 kbps during the entire video; whereas, the average bandwidthconsumed for the WMV file with Branch Repeater was approximately 206 kbps with a data spikeonly for a brief moment at the start of the video. These numbers show that introducing a BranchRepeater solution into a high definition WMV video environment would show approximately 89%reduction in the average amount of bandwidth consumed per HD video.

0 500 1000 1500 2000

MediaStream for XenDesktop withBranch Repeater

MediaStream for Native XenDesktop

Avg Data Throughput per Video (kbps)

Video Workflow - High Definition Video


23/30

Page 23

Conclusion

In conclusion, this paper provides customers with guidance for determining the amount of bandwidth required to transition branch office employees from a local desktop to a virtual desktophosted on Citrix XenDesktop. The graph shown in Figure 12 provides a collective representation of all the average bandwidth requirements discussed in this document.

Figure 22: Average Bandwidth Consumed per Session

When reviewing the test results represented in Figure 12 and integrating those results into a uniquecustomer environment, the following key topics should always be considered for any bandwidthassessment exercise:

1. The process for determining the bandwidth requirements for a XenDesktop solution in abranch office should always start with having a good understanding of the applications andcurrent network demand that the branch office employees have on the existing WANconnection. The application specific bandwidth numbers in this document should provideguidance for common applications, but more intricate applications such as a CRM or ERP

system should be thoroughly evaluated before making any conclusions regarding WANrequirements.

2. WAN utilization is another key component to consider when evaluating the WANconnection. When assessing WAN utilization, it should not be assumed that the averagebandwidth consumed for all users should consume 100% of the available bandwidth. If possible, the virtual desktop performance should be measured when the WAN connection iscongested to determine the acceptable overall percent of average WAN utilization beforeuser performance is impacted. To ensure that enough bandwidth is available, the maximum

0

200

400

600

800

1000

1200

1400

1600

1800

2000

Office InternetExplorer

Printing:Word

Printing: PDF Flash Video(server

rendered)

StandardVideo

HighDefinition

Video

K b p s

Average Bandwidth Consumed per Session

Native XenDesktop XenDesktop & Branch Repeater


24/30

Page 24

WAN utilization must be based on the most network intensive time of the day and theeffective available bandwidth.

3. Although sometimes difficult to predict, future users and application changes can also affectthe bandwidth requirements sooner than expected. The WAN connection selected should

have the potential for company growth without hindering existing user experience.

4. The other key factor when looking to optimize an existing or future WAN connection aspredominantly shown throughout this paper is the introduction of a Citrix Branch Repeatersolution into any branch office environment. As repeatedly shown throughout the results inthis document, the Citrix Branch Repeater can optimize a WAN connection, improve theoverall user experience, and potentially double the amount of users on an existing WANconnection.


25/30

Page 25

Appendix A - Hardware and Software Configurations

The Consulting Solutions lab located in Fort Lauderdale, Florida provided the following hardwareand software for this report in conjunction with our partnership with Login Consultants:

Component Operating system HardwareXenServer Pool Hosting

Virtual Desktops XenServer 5.5.0 4 physical HP DL360G5

2x Dual Core 2.66 Hz Intel XeonProc, 16GB RAM, 2x72GB hard

drivesXenServer Hosting

Infrastructure XenServer 5.5.0 HP DL360G5


drivesXenServer Hosting

XenDesktop Environment XenServer 5.5.0 HP DL360G5

2x Dual Core 2.66 Hz Intel Xeon

Proc, 16GB RAM, 2x72GB harddrivesXenServer Hosting

Branch Office Environment XenServer 5.5.0 HP DL360G5


drivesComponent Operating system Hardware

Login VSI File Share Windows Server2003 R2 SP2

HP DL360 G5 2.5Ghz Intel XeonProc, 1GB RAM, 1x72GB hard drive

Branch Repeaters Version 5.5.1Build 58.191613

Model 8520 (pair)

Apposite WAN Emulator Version 4.0.1 Apposite Linktropy Mini Table 4: Physical Hardware

Virtual Component Operating system Virtual Hardware Virtual Desktops Windows XP SP3 1GB RAM, 1 vCPU

SQL Server Windows Server 2008 2GB RAM, 2 vCPUs Active Directory Windows Server

2003 R2 SP21GB RAM, 1 vCPU

Citrix License Server Windows Server 2008 1GB RAM, 1 vCPUCitrix Provisioning Services Windows Server

2003 R2 SP21GB RAM, 1 vCPU

Citrix Delivery Controller with Web Interface

Windows Server2003 R2 SP2

2GB RAM, 2 vCPUs

Login VSI Launcher Windows Server2003 R2 SP2

4GB RAM, 2 vCPUs

Print Server Windows Server2003 R2 SP2

1GB RAM, 1 vCPU

Table 5: Virtual Hardware


26/30

Page 26

Software VersionLogin VSI Pro Version 2.0

Microsoft Office Office 2007 SP1Microsoft SQL Server SQL Server 2005

Citrix XenDesktop Version 4

Citrix Provisioning Services Version 5.1.1.2950Internet Explorer Version 7 Windows Media Player Version 11

Real Player Version 1.0.5Build 12.0.0.343

Table 6: Software Applications used in the report

Appendix B - Citrix XenDesktop Configurations

Property SettingFarm-Wide PropertiesConnection Access Controls Any ConnectionDesktop Delivery Controller\Session Reliability DisabledICA\Auto Client Reconnect Reconnect automaticallyICA\Keep-Alive 60 secondsHDX\Browser Acceleration Browser Acceleration: Enabled

Image Compression levels: MediumVariable Image compression: Enabled

Flash Enable Adobe Flash PlayerDesktop Group PropertiesBasic\Assignment Type PooledAdvanced\Client Options Colors: True Color (24-bit)

Connection:Encryption; 128-Bit Login Only (RC-5)Connection Protocols: ICA

Advanced\Logoff Behavior Restart the virtual desktopCitrix PoliciesBandwidth\Visual Effects\Turn off menu animation Enabled - Turn off Menu and Window AnimationsBandwidth\Visual Effects\Turn off window contentwhile dragging

Enabled - Turn off window content while dragging

SpeedScreen\Image acceleration using lossycompression

EnabledCompression level: Medium compression; goodimage quality

Session Limits\COM Ports DisabledSession Limits\LPT Ports DisabledSession Limits\OEM Virtual Channels DisabledSession Limits\TWAIN Redirection DisabledClient Devices\Resources\Audio\Microphones Enabled - Use client microphones for audio inputClient Devices\Resources\Audio\Sound Quality Enabled Medium sound quality; good

performance


27/30

Page 27

Client Devices\Resources\Drives\Connection Enabled Connect Client Drives at LogonClient Devices\Resources\Drives\Mappings Enabled

Turn off Floppy disk drivesTurn off CD-ROM drivesTurn off Remote drives

Client Devices\Resources\Optimize\Asynchronouswrites Enabled Turn on asynchronous disk writes toclient disksClient Devices\Resources\Ports\Turn off COMports

Enabled Turn off client COM ports

Client Devices\Resources\Ports\Turn off LPT ports Enabled Turn off LPT portsClient Devices\Resources\PDA Devices DisabledClient Devices\Resources\Other\Turn off OEMvirtual channels

Enabled Turn Off OEM Virtual Channels

Client Devices\Maintenance\Turn off auto clientupdate

Enabled Turn off Client Update

Printing\Client Printers\Auto-creation Enabled Auto-create the clients default printeronly

Printing\Client Printers\Legacy client printers DisabledPrinting\Drivers\Universal driver Enabled Use universal driver only if requested

driver is unavailableSecurity\Encryption\SecureICA encryption Enabled RC5 (128-bit) logon only

Appendix C Citrix Branch Repeater Configurations

Property SettingBandwidth Management>Status Softboost

Bandwidth Management>BandwidthScheduler>Bandwidth Consumption Full Bandwidth

Bandwidth Management>BandwidthScheduler>Bandwidth Limit (Send):

1425kbps

Bandwidth Management>BandwidthScheduler>Bandwidth Limit (Receive)

1425kbps

Service Class Policy>ICA AccelerateDisk based Compression

Service Class Policy>HTTP AccelerateDisk based Compression

Appendix D Login VSI Pro Configurations

Property SettingVSI Launcher ConfigurationType of connection Custom with CSVUser Credentials NANumber 1 to n (Varied based on workflow)


28/30

Page 28

Interval CustomCustom Command line CustomLocation of csv file File Share Path (datacenter)Auto log off NoVSI Workflow

Office 2007 Customized MEDIUM workflow to execute Officeonly VSI Pro FeatureIE 2007 Customized to run CORE workflow that executes

custom AutoIT based IE browsing script VSI Profeature

Video Customized to execute Flash, standard WMV, andHD WMV video

Appendix E HDX MediaStream Active Directory GPOs

HDX MediaStream for Flash is enabled or disabled through Active Directory Group Policy Objects(GPOs). The Citrix support provides two ADM templates that can be imported into theenvironment: HDX-Flash-Client and HDX-Flash-Server. Both of these templates are found on theXenDesktop 4 media in the W2K3\En\Support\Configuration folder.

Once the HDX-Flash-Client and HDX-Flash-Server ADM templates were imported into the GPOthat applied to the XenDesktop test users, the following settings were made:

Enable HDX MediaStream for Flash on the user device: Enabled Enable server-side content fetching: Enabled Enable HDX MediaStream for Flash for connections to the server: Enabled

Server-side content fetching list: Enabled and set to * so all URLs would be fetched

Appendix F - References

Login Consultants Login VSI Pro Benchmarking Tool: http://www.loginconsultants.com/index.php?option=com_content&task=view&id=231&Itemid=128

Citrix HDX Technologies: http://hdx.citrix.com

High Definition Windows Media Video (robotica.wmv):http://www.microsoft.com/windows/windowsmedia/musicandvideo/hdvideo/contentshowcase.aspx

HDX MediaStream for Flash Information:http://www.citrix.com/tv/#videos/635


29/30

Page 29

HDX MediaStream GPO Configurations:http://support.citrix.com/proddocs/index.jsp?lang=en&topic=/xenapp5fp2-w2k3/hd-flash-configure.html


30/30

Revision Change Description Updated By Date0.1 First draft Bhumik Patel & Carisa Stringer January 22, 2010

0.2 QA Paul Wilson January 28, 20100.3 Update Bhumik Patel & Carisa Stringer February 10, 20100.4 Final Version Bhumik Patel & Carisa Stringer March 5, 2010

About Citrix

Citrix Systems, Inc. (NASDAQ:CTXS) is the leading provider of virtualization, networking and software as a servicetechnologies for more than 230,000 organizations worldwide. Its Citrix Delivery Center, Citrix Cloud Center (C3)and Citrix Online Services product families radically simplify computing for millions of users, delivering applicationsas an on-demand service to any user, in any location on any device. Citrix customers include the worlds largestInternet companies, 99 percent of Fortune Global 500 enterprises, and hundreds of thousands of small businessesand prosumers worldwide. Citrix partners with over 10,000 companies worldwide in more than 100 countries.Founded in 1989, annual revenue in 2008 was $1.6 billion.

2010 Citrix Systems, Inc. All rights reserved. Citrix, Access Gateway, Branch Repeater, Citrix Repeater,HDX, XenServer, XenApp, XenDesktop and Citrix Delivery Center are trademarks of Citrix Systems, Inc.and/or one or more of its subsidiaries, and may be registered in the United States Patent and Trademark Officeand in other countries. All other trademarks and registered trademarks are property of their respective owners.

xendesktop to branch offices

Documents