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Archive for the ‘Citrix XenDesktop’ Category

Decision Making Process between TS & VDI

Posted by Brajesh Panda on March 8, 2010

On Need

  • What User needs to work?
    • Application
      • Then Session Solution is best i.e. Windows RDS/TS , Citrix XenApp
    • Desktop
      • Then individual Physical Desktop/Blade PC/VDI Solution is best


  • What IT Strategy is expecting?
    • Easy Administration & Base required Control with bare minimum features
      • Windows Remote Desktop Services
    • Advance Administration & More Control with competitive features
      • 3rd Party solutions
  • Solution Pros & Cons
    • Dedicated Desktop
    • Isolated Security
    • Isolated Processes
    • Application Conflict

On Financial

  • Another major decision making factor is whether we are looking for purely VDI, TS or Hybrid environment by mixing both of them to gain mileage on existing investment
  • Any infrastructure need two types of investment for new infrastructure
    • Hardware Equipment
      • VDI need much more fat & heavy hardware equipments as comparison to TS environments
      • Exact size can be determined in sizing phase
      • Other Infrastructure investment like Power, Cooling & Management is generally less in TS environment as comparison to VDI environment
    • Software Licensing
      • Software Licensing is one of most confusing & critical investment factor in this kind of scenario. TS & VDI has their unique licensing proposition which is discussed under below.



Terminal Licensing Walkthrough

Microsoft Terminal/Remote Desktop Services

Citrix Metaframe/Presentation/XenApp

Windows Terminal Servers OS Licenses

Citrix Server Windows OS License

Windows TS/RDS CAL

Citrix Infrastructure Component Licenses


Windows TS CAL


Citrix Concurrent Licenses

  1. 100 User Environment for Microsoft Terminal Services
    1. Individual TS/RDS CAL:        100 x $120 =$12000
    2. Plus other infrastructure server license costs.
  2. 100 User Environment for 3rd Party Terminal Services like Citrix
    1. Individual TS/RDS CAL:        100 x $120 = $12,000
    2. Citrix Concurrent Licenses:     100 x $400 = $40,000
    3. Plus other infrastructure server license costs.

    Advantage:    In Terminal Services environment TS CAL or RDS CALs are one time purchase along with OS Licenses. No renewals required. Citrix provides Software Assurance renewal agreements for support but it is optional. Citrix concurrent license cost depends on features & editions we are purchasing. Over here we have considered base standard edition.

Virtual Desktop Licensing Walkthrough

Microsoft Remote Desktop Services (For VDI)

3rd Party VDI Infrastructure

Windows RDS Infrastructure Windows Server OS Licenses

VDI Infrastructure Windows Server OS Licenses

Virtualization Infrastructure Licenses

Virtualization Infrastructure Licenses

Windows RDS CAL

VDI Client Licenses

If Client OS is Covered under MS Software Assurance Agreement – Need Windows VECD for SA Licenses

for all client devices

If Client OS is Thin Client – Need Windows VECD
License for all client devices


  • VDI environment can be accessed from a Full Fledged PC, Laptop or from Thin Client & to access VDI environment we need VECD Licenses
  • All Client PCs or Laptops (from where we are accessing VDI environment) running with Windows OS must be covered under Software Agreement with MS. After these devices get covered under SA, we need Windows VECD for SA License to access VDI environment.
  • All Thin Clients must have Windows VECD Licenses to access VDI environment
  • Windows VECD for SA cost $23/year & Windows VECD cost $110/year
  • In a enterprise environment VECD can be purchased for part of desktops/thin clients but only these desktops will be used to access VDI environment
  • From each VECD licensed devices you can access 4 Virtual Machines from your VDI Farm
  • You can run unlimited VMs inside the Virtual environment
  • VECD provide Home Use rights (Access VMs from home). In case of shared VECD Devices only primay named user will able to access.

    VDI Scenario

  • Current Number of PCs: 200
    • VDI Client PCs (From where users will access VDI) = 150
      • PCs covered under SA: 50
      • PCs not covered under SA: 100
  • Current Number of Thin Clients: 250
    • VDI Client Thin Clients (From where users will access VDI) = 200
  • Number of VDI Users: 500
  • Max Concurrent users: 350

    Yearly License Requirement for MS VDI

  • Windows VECD for SA = 50 x $23/year
  • SA Upgradation for PCs = 100 x SA Price/year
  • Windows VECD for SA for SA upgraded PCs = 100 x $ 23/year
  • Windows VECD for thin clients = 200 x $110/year
  • Perpetual Windows RDS License= 500 x $120
  • Plus Infrastructure Server OS Licenses

    N.B:    RDS Licenses can be purchased under standalone perpetual purchase or under volume license key with VDI suite offering. RDS CALs are Named User or Device based licenses.

    Yearly License Requirement for VMware, Citrix VDI

  • Windows VECD for SA = 50 x $23/year
  • SA Upgradation for PCs = 100 x SA Price/year
  • Windows VECD for SA for SA upgraded PCs = 100 x $ 23/year
  • Windows VECD for thin clients = 200 x $110/year
  • Concurrent VMware View/XenDesktop Client Packs for concurrent Users
  • Plus Infrastructure Server OS Licenses
  • Plus VDI Infrastructure Standalone Software licenses

TS & VDI Hybrid Solutions

  • Windows RDS CAL provides access to VDI (Remote Virtualization Host) & Terminal Servers (Remote App Servers) through Remote Connection Manager & Session Host Severs.
  • XenDesktop Enterprise provides access to XenApp for Virtual Desktops inside VDI infrastructure

If current infrastructure is using both Windows Terminal & Citrix Presentation Server, as low capital investment Windows RDS service can be kicked off, where both Windows Terminal Service & VDI Facility can be utilized under a single CAL! As Citrix XenDesktop Supports MS Virtualization Farm In future as per requirement XenDesktop Infra can be introduced to the environment for rich features & better control.


Posted in Citrix XenDesktop, Microsoft VDI, Virtual Desktop Solution | Tagged: , , , | 1 Comment »

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