VDI solutions

• The dominant virtual desktop applications are VMware Inc.’s VMware View and Citrix Systems Inc.’s XenDesktop.

View runs on VMware’s vSphere hypervisor platform.
XenDesktop can run on Citrix’s server virtualization platform, XenServer, vSphere or Microsoft’s Windows Server 2012 Hyper-V platform.
Microsoft also offers a virtual desktop product called Microsoft Windows Server 2012 Remote Desktop Services, and Dell Inc. has its own VDI offering called vWorkspace.

Persistent vs. stateless desktops
A persistent desktop contains everything the user needs within the virtual desktop image and the individual VM.
All of the applications, documents, settings and profiles are tied to the individual desktop and VM.
A stateless desktop uses one master image for all users (also referred to as a “golden image”), and the profiles, settings and applications are streamed to the thin client

A stateless environment uses a single image for all virtual desktops, eliminating the need to store individual images for each user.
Instead of updating each virtual desktop individually, an update or patch to the one image updates every virtual desktop.
you can begin your deployment with a persistent setup and migrate to a stateless environment later.

http://searchvirtualstorage.techtarget.com/feature/Control-VDI-costs-for-storage-by-careful-configuration-planning

• Citrix XenDesktop 4.0 Platinum

judgment: "Suitable for departmental-level deployments and for SME-class organizations."

 Strengths:

    Flexible delivery
    Supports multiple virtualization servers
    Strong user-experience feature set
    Diverse endpoint OS support
    Strong WAN performance
    Rich supporting ecosystem

 Weaknesses:

    Security logging and auditing of administrative actions
    3 year support for entire product portfolio

VMware View 4.01 Premier Edition

Judgment: "Not...an enterprise-class SHVD platform"
Note: "Upcoming VMware View 4.5 (in beta) release satisfies the required feature shortcomings."

Strengths:

    Rich integration with VMware vSphere
    Solid but incomplete core feature base
    PC-over-IP performance better than expected
    Simple deployment
    Active directory integration
    Enterprise management

Weaknesses:

    Role-based access control or security hardening guidelines
    Enterprise management integration
    No user application self service
    Low-bandwidth WAN support
    Supports only VMware backend
    Management console scalability limited
    Win7 Guest OS support


http://www.cio.com/article/2417986/virtualization/desktop-virtualization--top-vendors-still-miss-the-mark.html?page=2

• SHVD (Server Hosted Virtual Desktops) Infrastructure Costs: VMware View 4 vs. Citrix XenDesktop 4

SHVD also provides greater user flexibility by allowing them to access their desktop from a variety of end points, which can improve productivity for meeting organizational requirements and increasing profitability.
vendors have developed unique virtual infrastructure platforms.There are many variables involved in determining implementation expenses, but they principally fall into three distinct categories: server, storage, and software
All three of these cost elements should be carefully evaluated prior to investing in a SHVD solution to ensure value is achieved in deploying a solution that best meets organizational requirements

Comparable implementations have been established based on recommended configurations derived from publicly available sources
The configurations have been developed to include the minimum number of components necessary to support small (800 VMs), medium (3000 VMs), and large (10,000 VMs) infrastructures
The resulting configuration profiles were submitted to their respective vendors for independent review and their comments have been incorporated to ensure a fair and accurate comparison
It should be noted that this analysis did not include a full functional comparison as the feature sets of the two products are not completely identical
Each organization should perform product evaluations based on its own unique requirements. The data provided here is intended to help indicate a starting point for that process

1Server Components
All SHVD implementations require physical servers for hosting, managing and delivering virtual desktop instances.
These hardware components are typically deployed in data centers and supported by acentralized IT operations team.

Although a total cost of ownership (TCO) evaluation would involve all infrastructure expenses including those for
power consumption
HVAC
backup and disaster recovery(BDR)
maintenance
support staff compensation for all managed components
this evaluation will assume such secondary costs to be roughly equivalent between the two solutions and only focus on the areas where the primary cost factors differ


Virtual desktops in a VMware View implementation are maintained on a series of physical Desktop Servers.
Each Desktop Server requires a minimum of 48 GB in memory to host up to 142 virtual machine (VM) instances.
A VMware View Connection Server is also required for every 1000 VMs supported for brokering desktops and controlling user access.
Centralized virtual image management of the environment is performed by VMware View Composer software which can be installed on vCenter Servers that also provide storage management functionality.
These combined management platforms can support up to 1000 VMs each, but can be consolidated through server virtualization so that a single physical vCenter Server can support up to five such implementations.
Similarly, SQL servers necessary for hosting the vCenter and View Manager databases can also be consolidated through server virtualization at a ratio of 5:1
VMware recommends the SQL Server and vCenter Server be combined into a single system on implementations of less than 1000 VMs

With Citrix XenDesktop, 125 VMs can be supported on each XenServer with a minimum of 72GB of memory.
A cluster of Provisioning Servers, which is utilized for managing and delivering virtual images, can each reliably support 2000 VMs with one additional server added for fault tolerance (as recommended by Citrix).
Functionality for managing, maintaining and optimizing virtual desktop connections is provided by Desktop Delivery Controllers (DDCs).
For DDC’s, Citrix advises that a single physical server can provide the resources necessary to reliably support 10,000 VM
A XenDesktop infrastructure also commonly includes 2 Web Interfaces that allow users to access their published resources through a standard web browser
VMware, however, demonstrated roughly 60% greater efficiencies in memory utilization which contributed to the VMware View solution requiring 19% fewer servers than Citrix XenDesktop in order to host 10,000 users

2Storage Requirements
both VMware and Citrix utilize shared storage solutions for desktop images and software requirements.
For sizing purposes, an average of 3 images per desktop has been assumed, each with a size of 20 GB
VMware View Premier is able to significantly reduce storage requirements through the use of linked
clones, which is a process that allows a master replica to be created to which dependent VMs can be
linked so that only the differences from the master (the delta) need to be stored.

For Citrix XenDesktop, an average temporary storage requirement of 5 GB for each supported desktop has been calculated for this environment
This storage is used to accommodate the transient write caches associated with Provisioning Server virtual disks
Additionally, each provisioning server needs 20 GB for its application requirements and a fixed 100 GB needs to be collectively available to all
provisioning servers as a caching area for live images.
Desktop Delivery Controllers (DDCs). and Web Interfaces each require 5 GB for application installation

3Software Costs
VMware offers two editions of its View solution
The Enterprise Edition offers all software components necessary for full SHVD deployment,including high availability and dynamic provision capabilities
The Premier Edition also adds application virtualization and enables offline desktops

Citrix offers three versions of its XenDesktop solution
The standalone VDI Edition provides basic virtual desktop functionality and is sold with either a cost per individual user or concurrent user license model
More advanced virtualization management capabilities and application virtualization are added with the Enterprise Edition
the Platinum Edition offer the complete breadth of XenDesktop’s SHVD feature set, including advanced access control and server level monitoring

SHVD server memory utilization, density of VM per server, and level of concurrency.
All three of these factors are influenced by the operational conditions of the enterprise in which the implementation will be utilized

http://www.vmware.com/files/pdf/view/VMware-View-vs-Citrix-XenDesktop-EMA.pdf

• Comparing VDI solutions: VMware View and Citrix XenDesktop

VMware's much-vaunted PCoIP protocol is incompatible with their security server, along with the fact that Citrix historically maintains an edge over VMware as a client-friendly, firewall-friendly connectivity suite.
XenDesktop is compatible with ESX, and that might be of interest to existing VMware shops
http://www.computerweekly.com/news/1391338/Comparing-VDI-solutions-VMware-View-and-Citrix-XenDesktop

• Desktop virtual infrastructure now includes new cloud-based options

The introduction of cloud-based computing models for VDI (known as desktop as a service or DaaS) now offers a combined benefit and challenge to the IT decision maker
Whereas on-premise data center-hosted VDI represented a known model that has been tested and refined over the years, cloud-based VDI is the new kid on the block

With many VDI solutions, the active desktop state can be preserved, enabling users to pick up right where they left off.
open-source solutions from StackVDI, QVD, and others.

*VDI delivery methods

Historically, solutions first began with the typical on-premise server-hosted virtual desktop model, focusing on the data center

As VDI and cloud computing have matured, a second software-as-a-service(SaaS) model of desktop computing has been reborn in the form as DaaS
In its simplest form, DaaS is VDI in the cloud
as with all cloud-based solutions, the customer must rely upon the cloud service provider (CSP) to deliver critical infrastructure that is no longer under the control of the IT organization
DaaS solutions are marketed as being able to handle the challenges of traditional VDI, such as complexity and cost.
In DaaS, customers pay a monthly flat fee and are able to obtain a VDI infrastructure without the initial investment.

The third option consists of a hybrid approach that leverages both the on-premise and cloud-based models

*AWS
AWS offers Amazon Workspaces as its VDI solution.
Workspaces represents a cloud-based managed desktop computing service, Amazon's DaaS model for VDI
Amazon WorkSpaces enables customers to choose from a range of Amazon WorkSpace bundles that provide options for CPU, memory, storage and applications.
In conjunction with AWS Directory Services,
Amazon WorkSpaces can integrate with a company's existing Active Directory infrastructure
Users also have the flexibility to install their own applications or use applications available through Amazon WorkSpaces
Amazon Workspaces supports desktop state persistence that provides a desktop anywhere model.
The WorkSpaces Sync client also enables users to synchronize documents between their Amazon WorkSpace and other computers.
Workspaces also provides support for USB devices, with the exception of printing.

Citrix
Citrix provides two options for customers seeking VDI: VDI-in-a-Box and XenDesktop.


http://www.networkcomputing.com/applications/guide-to-vdi-evaluating-top-vendors/d/d-id/1319116?page_number=1

• View planner is a workload simulator for VMware View environments that can be used to simulate a number of desktop workers, to verify the sizing of a given VMware View environment.

It can also be used to test the impact of a change in your VMware View production environment.
i.e. what is the impact of adding 512mb RAM to all your desktops, adding an additional vCPU or ramping up the number of desktops?
View Planner 2.0 is the natural successor to RAWC, meaning that RAWC is now EOL.
http://www.vpeeling.com/?p=252

• VMware Horizon View is a virtual desktop infrastructure (VDI) platform based on VMware vSphere virtualization

Step one: Research VMware View features
VMware ThinApp for application virtualization and vShield Endpoint for antivirus integration

Step three: VDI management
One of VDI's selling points is how it enables bring your own device (BYOD) within an organization
Employees purchase smartphones and tablets -- and apps that run on these devices
VMware offers security features in View 5 and newer versions that help admins deal with BYOD situations and other security considerations.
VMware updated View from version 5.1 to VMware Horizon View 5.2 in 2013,

http://searchvmware.techtarget.com/feature/VMware-View-best-practices-for-every-stage-of-VDI-implementation

• VMware View implementations architectures

 

• Citrix XenDestop implementations

• Smart client

Smart client is a term describing a computer application environment which

delivers applications over a web Hypertext Transfer Protocol (HTTP) connection

does not require installation (or provide automated installation and updates)

automatically updates without user action

has the look and feel of desktop applications

The term "smart client" was chosen to refer to simultaneously capturing the benefits of a "thin client" (zero-install, auto-update) and a "fat client" (high performance, high productivity).

https://en.wikipedia.org/wiki/Smart_client

• Smart Clients

http://www.chippc.com/products/smart-clients

• Evaluating Your Options for Desktop Virtualization (Part 1)

VDI, or Virtual Desktop Infrastructure, is a technology in which a server is used to host desktop operating systems. This technology is similar to what is used for server virtualization, except that there is usually a mechanism in place to link users to individual virtual desktops so that each user is connected to a different virtual desktop.

http://www.virtualizationadmin.com/articles-tutorials/vdi-articles/general/evaluating-options-desktop-virtualization-part1.html

• Microsoft Virtual Desktop Infrastructure (VDI) Explained

A centralized desktop delivery solution, Microsoft Virtual Desktop Infrastructure (VDI) is. The concept of VDI is to store and run desktop workloads including a Windows client operating system, applications, and data in a server-based virtual machine (VM) in a data center and allow a user to interact with the desktop presented onto a user device via Remote Desktop Protocol (RDP)

http://blogs.technet.com/b/yungchou/archive/2010/01/06/microsoft-virtual-desktop-infrastructure-vdi-explained.aspx