Citrix_gyuzgzugzgusgvsjzygsuyvsuvNew.pdf

Cloud computing

1. Citrix
Server
Edrees Shakeeb Al-Ghawri
Abdullah Waleed Al-Shaibani
Abdullah Owais Al-Ghawri

2. Introduction
Inmanypeoplesdaytodayjobs,they
regularlycomeacrossCitrixtechnologies,
mainlyusingthetechnologyforremote
accesswhentheyworkfromhomeor
whentheyremotelyconnecttosystems
inotherofficesandregions.Citrix
technologyismorethanjustremote
accesstechnologyandinthisarticle,a
deeperdiveintolearningmoreabout
Citrixisundertaken.

3. What is Citrix and how it
works?!
CitrixSystemsisacompanyheadquarteredin
theUnitedStatesinFortLauderdale,Florida.
Citrixprovidetechnicalproductsfor
networkingandvirtualizationwithit’svirtual
apps(formelyXenApp)andvirtualdesktops
(formelyXenDesktop)beingtwoofit’smost
popularproducts.

4. What is Citrix and
how it works
01

5. Citrix is a company
oThefullnameofthiscorporationisCitrixSystems,whichishead
quarteredinFlorida,USA.
oCitrixSystemshasgrownrapidlyfrom1994whenitwascreatedby
EdIabucci.EdisnolongerpartoftheCitrixsetupandhasbeen
supersededbymanydifferentCEO’sincludingMarkTempleton,
RobertCalderoni,KirillTatarinovandcurrentlyDavidHenshall.

6. Citrix primarily focuses on Thin Client and Virtualization technologies
but they have also expanded into other areas including networking
technologies.
Citrix is a company providing technology allowing remote access type
functionality to applications and computer desktops. Citrix
technology works by presenting information from one source to
another using clever and sophisticated technologies.
Citrix provides tech products
Citrix Systems develops several leading products which are used by
many famous organisationsworldwide.

7. The user uses a search engine such as the likes of Google, Yahoo,
Bing or one of the other many search engines. The user enters some
words into Google’s search box and when the ‘search’ key is pressed,
the results appear within a few seconds.
Thin Client technology also known as Server Based Computing (SBC)
has made Citrix Virtual Apps a market leader, but what is Thin Client
technology?
Thin Client and Virtualization leader
Before lifting the lid on how Thin Client technology works, let’s look at
another technology which many people use in their day to day lives.
This technology focuses on searching the world wide web (Internet).

8. Once this information is found, it is sent back to the user’s computer,
where it is displayed as the search results, as shown by the
screenshot below.
This search information is not stored on the user’s computer, that is,
there isn’t a massive store of all the websites Google knows about
hiding in the user’s computer.
Thin Client and Virtualization leader(followed)
In reality whathappens is when the user presses ‘Search’, their search
request is sent to a data centre, where a series of very powerful
computers search their data banks for the relevant information that
matches the users search request.

9. The word processor exists on a powerful set of computers in the data centre
from where all the processing is done. The thin client technology represents the
word processor to the user’s computer, as though it was actually installedon
their computer.
In the Thin Client world, the processing of information takes place
away from the user’s computer, typically on a powerful set of
computers in a data centre, just like the search engine example
earlier.
Thin Client and Virtualization leader(followed)
Instead of web pages being sent to the user’s computer, the thin
client technology works with applications and the presentation of
these applications. Soan application such as a word processor in thin
client technology doesn’t exist on the user’s computer.

10. Later onthis section, the steps taken to connect to the application
shown in this screenshot, will be shown.
.
The first screenshot below, shows an application running remotely
which for all intents and purposes looks like it is actually installedand
running on the computer, when in fact it is not.
Thin Client and Virtualization leader(followed)
At the bottom right of this screenshot there is an icon circled in red,
which is the Citrix plug-in icon and this when clicked, will show the
application is actually runningremotely.

11. Sothere could have a computer in New York City which has word
processing software installedand a user could connect to this
computer say from a computer in London and use the word processor
without having the word processing software actually installed
(resident) on our computer in London.
To reiterate what has been covered so far, in the world of Thin Client
technologies like Citrix Virtual Apps, use a computer to remote control
an application installed on another computer.
Citrix technology how it works?
The other computer does all the grunt of processing the application
and dealing with the usersinputs that is, changes in their mouse
movements along with keyboard strokes and dealing with outputs,
that is, changes to the applications user interface, which is, how the
application is presented to the user.

12. Application and Desktop Delivery: Using Citrix Virtual Apps and Citrix
Virtual Desktops, users can run applications or full Windows desktops
on a remote server. These are delivered to the end user's device
through a secure network connection, providing access to business
applications without needing them installed locally.
Virtualization: Citrix uses server virtualization to run applications and
desktops on centralized servers rather than on local devices. This
allows users to access these resources remotely from any location.
Citrix technology how it works?
Citrix Hypervisor (XenServer): This is the underlying technology that
virtualizes the server environment, enabling multiple instances of
operating systems or apps to run on the same physical server.

13. HDX Protocol: Citrix's proprietary protocol called HDX (High-Definition
Experience) ensures that virtualized applications and desktops are
delivered with high performance. HDX optimizes bandwidth, improving
the user experience even in low-bandwidth situations.
Citrix technology how it works?
Citrix Gateway: This serves as a secure access gateway for users
connecting to Citrix resources. It manages authentication and
establishes encrypted connections between the user and the Citrix
environment, ensuring secure access.
Citrix Workspace: This platform integrates access to all apps, data,
and services, providing users with a unified interface to manage and
use their resources.

14. Load Balancing: Citrix technology uses load balancers (e.g., Citrix
ADC) to manage traffic distribution among multiple servers to ensure
that no single server is overwhelmed, ensuring better performance
and reliability.
Citrix technology how it works?
Security: Citrix provides built-in security features, such as multi-
factor authentication, end-to-end encryption, and secure browsing
capabilities, to ensure secure remote access for enterprise
environments.

15. ●WhilsttheThinClientapproachlooksatprocessingtheapplication
logicremotely,thatisrunningtheactualapplicationonadifferent
computertowheretheuserisusingitandinturnpresentingthe
userwithimagesofwhatishappeningremotely.
●TheFatClientapproachlooksatprocessingtheapplication
locally,thatisonthecomputerbeingusedbytheuser.Thisis
thetypicalapproachusedbymostcomputerusers,wherethey
useacomputerathomeforinstance,whichdoesallthe
applicationprocessing.
●Thescreenshotabove(ThinClientversusFatClient),theword
processingsoftwareonthethinclientisrunningonapowerful
computerinthedatacentre.Whilstwiththefatclient
approach,thesoftwareisrunningonthecomputeritself.
Thin Client vs Fat Client
Traditional vs Thin Client approach

16. Thin Client
Software
02

17. Does A Thin Client Have
An Operating System?
(Important Info)
Thin clients are stripped down computers
and many people wonder whether thin
clients actually use an operating system like
normal computers. Further investigation to
find out if this was the case will help
establish if thin clients do indeed have
operating systems.

18. Does A Thin Client Have
An Operating System?
Athinclientdoeshaveaoperatingsystembutthisislimitedin
functionalityandisnotafullyoperationaloperatingsystem
usedbythickclientslikelaptopsanddesktopcomputers.The
thinclientoperatingsystemisinstalledintheflashmemory
storageandprovidesaccesstoperipheralslikeUSBdrives,
localprintersandallowsconnectionstobemadetoremote
serversusingremotecontrolprotocolslikeRDP,ICAandPCoIP.
Theoperatingsystemscapturesmousemovementand
keystrokesrelayingthemtotheremoteserversandupdatesthe
desktopdisplaybasedontheinformationsentbackfromthe
remoteservers.

19. Does A Thin Client Have An Operating System?
(Important Info)
1.Microsoft Windows 10 IoT Enterprise (WIE)
2.Microsoft Windows Embedded Standard (WES) 7E
3.ThinOS (Wyse)
4.ThinLinux (Wyse)
5.ThinPro (HP)
6.Smart Zero Core (HP)
7.OpenThinClient
8.ThinStation
The following operating system choices are
available:

20. 1 Microsoft Window 10 IoT Enterprise
The Internet of Things, hence the
abbreviation IoT in the title of this
operating system is used to appeal
to many other uses other than just
thin clients for this operating
system, as this operating system is
capable of working in smaller
powered devices, giving it a smaller
footprint compared to other
operating systems.
Microsoft Windows 10 IoT
Enterprise is a slimmed down
version of Windows 10 designed for
embedded systems, that is where it
is installed on memory (flash) and
this memory is part of the device.
Microsoft Windows in it’s different
versions is probably the most
popular thin client operating system,
being installed across many devices
and being offered as an option from
many thin client vendors.

21. ThinOSis a custom-built operating system from Dell, owners of the
Wyse brand. It’s marketed as the most secure of the thin client
operating systems, based on its locked down architecture which limits
the execution of security exploits. One of the ways this is done, is to
remove any capacity to download locally onto the thin client using a
browser, which has been removed.
Precursor to Microsoft Windows 10 IoT Enterprise and based on
the older Windows 7 line of Microsoft operating systems. This is
still available in some of the older thin clients, testament to the
increased lifespan thin client devices have over their desktop
computer rivals. Again this is a stripped down version of the desktop
variant of this operating system, specifically modified to be able to
run on lower powered devices.
2 Microsoft Windows Embedded Standard
3 ThinOS (Wyse)

22. ThinProis based on Linux and is used by HP for their thin clients.
ThinProis hardened by locking down the file system and
incorporating firewall software. HP Device Manager software is used
to manage thin clients running ThinPro.
ThinLinuxis based on SUSE Linuxand is a 64-bit operating system.
It is specifically designed for thin clients and was developed by Wyse.
ThinLinuxcan integrate with management tools like Wyse Device
Manager (WDM).
4 ThinLinux(Wyse)
5 ThinPro (HP)

23. ThinStationis based on CRUX Linux and is another open source thin
client operating system. This too is designed for use on repurposed
hardware like desktop computers and laptops coming to their end of
life using their desktop operating systems like Microsoft Windows 7.
Another Linux based operating system from HP with support for
Microsoft RDS (RDP), VMWare PCOIP, VMWare Blast Extreme and
Citrix HDX (ICA).
6 Smart Zero (HP)
7 ThinStation

24. What are Citrix Virtual Apps? (VDI Desktop Tech)
So, what is Citrix Virtual Apps? Citrix
Virtual Apps is the latest version of
Citrix’s thin client product line,
originating from Citrix WinFrame, the
first product Citrix launched in
remote access of applications and
desktops space to Citrix MetaFrame,
then Citrix Presentation Server and
Citrix XenApp.
Citrix Systems worked with Microsoft
to help develop their Windows
Terminal Service (WTS) and later
Remote Desktop Service (RDS). Citrix
Systems got to keep certain
functionality they’d developed for
themselves.

25. What are Citrix Virtual Apps? (VDI Desktop Tech)
This is exactly how the Citrix Virtual
Apps (including previous versions
called Citrix XenApp, Presentation
Server, MetaFrameand WinFrame)
are positioned. They provide an
improved experience for people using
and managing their Windows Server
and RDS (including WTS)
components.
Just as with Citrix XenApp, Citrix
Presentation Server and its
predecessor Citrix MetaFrame, all
have been developed outside the
joint development work Citrix does
with Microsoft with its RDS and WTS
products.

26. Citrix Virtual Apps Popularity
There are many reasons why Thin Client technologies such as Citrix are
popular, not only because Citrix is a great company which has the vision to
make great products but because Citrix actually develops products which
organisationsneed.
Citrix have been very clever in the way they’ve brought out other smaller
companies, which has not only opened up new markets for them, but
enhanced their already excellent product range.
Technology aside, one of the main reasons for using Citrix is cost especially
Total Cost of Ownership, known as TCO for short.

27. Citrix Virtual Apps Popularity
▪Citrix Systems develops Thin Client products such as Citrix Virtual Apps.
▪Microsoft RDS (formerly Windows Terminal Services) provides the engine for Thin
Client type computing.
▪Citrix Virtual Apps works with Microsoft Remote Desktop Services (Windows Server
2012, Windows Server 2016 or Windows Server 2019).
▪Fat clients run applications locally that is, on the computer being used by the user.
▪Thin clients access applications being run remotely and are not involved in the
actual running of the application.

28. Terminology introduced below shows what the technology involved is and
what it actually does, startingfrom the basics and building up.
Key Technical Concepts

29. The ‘personal computer’ or ‘PC’ for short has become an
important part of the lives of many during the technical
advances made in the past twenty years.
Personal Computers
Personal computers are used at home, at work, in internet cafes to
schools. These computers are used to run software such as word
processors, spreadsheets, web browsers (such as Microsoft Internet
Explorer, Mozilla Firefox, Google Chrome, Opera) to specialist business
applications.

30. For the purpose of this course, workstations and personal
computers will be known as desktop computers, as this is also
another term used widely to describe personal computers.
Workstations
Personal computers can also be called workstations, especially in the
workplace and generally have slightly more powerful specifications.

31. Portable versions of desktop computers are known as laptops and these are
designed to be powerful, yet provide this power on the move, with improved
battery life in a smaller form factor. Laptops have become lighter over the
years and this improved portability has made them more widespread.
Laptops
Desktop computers run desktop operating systems such as Windows XP,
Windows 7 and so on. These desktop operating systems are designed to
provide functionality for using software from word processors to web
browsers.
Desktop Operating Systems

32. Servers
There are other types of computers called ‘Servers’ which are
computers with similar components to desktop computers such as a
processor (to do the calculations, also known as a CPU –central
processing unit) memory, disks (also known as hard drives) and these
components may be more powerful than their desktop computer
counterparts.

33. ●Whatreallyseparatesthedesktopcomputerfromtheservercomputeristheoperatingsystemwhichisused.Ona
desktopcomputer,thedesktopversionsofMicrosoftWindowsincludingWindowsXP,WindowsVistaandWindows7is
used.SomedesktopcomputersmayhavedesktopoperatingsystemsfromAppletoLinuxdesktopderivativessuch
Ubuntu,FedoraandDebian.
●Ontheserver,serverbasedoperatingsystemswillbeused,soforWindows,MicrosoftWindowsServer2003
andMicrosoftWindowsServer2008arepopularchoices.Ifit’sgoingtobeaLinuxbasedserver,thenRedHat
Linuxisapopularchoice.
●Theseoperatingsystemsaredesignedtoutilisetheserverhardwaremoreappropriatelythanadesktop
operatingsystemwould.Moreover,theserveroperatingsystemsaredesignedtodealwithmultipleusers,
whilstadesktopoperatingsystemisdesignedtodealwithasingleuser.
●Aserveroperatingsystemwouldnotideallybeusedinthesamewayasadesktopoperatingsystem,thatis,
itisinstalledonadesktopcomputerandthenusedforsoftwaresuchaswordprocessing.
●Thisislikeusingabusinsteadofacar,totransportasingleperson.Itisjustanoverkillofthepoweravailable
todosomethingwhichcouldbedonewithless.
Server Operating Systems

34. Servers could be assigned a ‘file server’ role and would therefore be involved in
filing information (storing information on their disks) which can be retrieved
when required.
Server roles
Other server roles include email servers, web servers, database servers and
authentication servers to name a few.
Servers can be configured to provide different roles, that is, a server can be
assigned a particular duty to perform. So a server could be assigned the role of
‘print server’ and it would deal with printing, by sending print requests to the
appropriate printers.

35. ●Serveroperatingsystemstendtooperateinaclient/serverfashion,
wherebytheclient,whichisthedesktopcomputer(aswellas
laptopsandsmartphones),connecttotheserver.
●Dependingonhowtheserverisconfigured,thedesktop
computeruserwillbeabletoprint,storetheirfiles,
authenticate,sendemailsandsoonusingtheirconnection
fromtheirdesktopcomputertoaserver.
●Asingleserverwilltendtohavemanyclientsthatisdesktop
computers(aswellaslaptops)requestingservicesfrom
printingtoemail(subjecttowhatservicetheserverissetupto
provide)fromtheserver.
●Theservicesrequesteddependonwhatroletheserveris
configuredfor,soifitisconfiguredasanemailserver,itwill
sendandreceivetheemailsentfromtheuser’sdesktop
computer(aswellasfromlaptopsandsmartphones).
●Thescreenshot‘ClientsandServers’,aboveshowsseveral
differentclients,laptops,computersandsmartphones
connectingtoanemailserverandawebserver.
Client/Server
Client/Server

36. 32-bit operating systems can use directly 4 gigabytes (Gb) of
memory, whilst 64-bit can directly access up to 2,000 gigabytes (Gb)
of memory. This means in theory, more programs can be used on 64-
bit machines. Only computers with 64-bit processors can use 64-bit
operating systems.
There’s a lot of talk about 64-bit operating systems, as this is the next
step in the evolution of computing. Without getting too technical, the
difference between 32-bit and 64-bit operating systems is the amount
of memory they can use efficiently.
32-bit versus 64-bit