Please Help!? Definition of Citrix vs Terminal Services question...

Citrix Presentation Server is not a stand alone product; it requires Terminal Services in Application Mode. This of course means that you not only need Citrix Licenses, but TS CALs (which are, unlike the Citrix licenses, NOT concurrent) as well if you want to use Presentation Server. PS offers enhancements of terminal services, and it has its own protocol, but it still needs the OS to provide the basic terminal services.

So for the small company (that may need to run several TS sessions) is there a benefit to running citrix?  Why would you even use citrix and not just a TS server in Application Server Mode?  Thanks.

One other dumb question..  Can you upload files to the server using citrix an TS?  Thanks.

Also, considering in a metaframe environment, RDP is required for proper functionality, RDP (3389)must be open in addition to 443 (for citrix).  So while Citrix is easily accessible, is it safe to say that the TS part of the equasion can become a bottleneck when connecting from hotels and such using a laptop?

Last of all, do you need a VPN to connect to the Terminal Server (2003)?  or can you just connect using the TS connectoid without the VPN?  Thanks.

My general opinion is that TS is fine for most smaller offices. Terminal Services has matured enough that it can handle most needs without the addition of Citrix. My favorite Citrix features above TS are published applications and better printing support.

>>>Can you upload files to the server using citrix an TS?
Yes, the client's hard drive can be mapped as a drive letter in your citrix/TS session, so you can copy files to/from your local machine.

>>>is it safe to say that the TS part of the equasion can become a bottleneck when connecting from hotels and such using a laptop
I'm not quite sure what you're asking here, but if you are referring to the protocols used, I doubt you wil notice a difference between RDP and ICA (Citrix), especially when using a high-speed connection.

>>>do you need a VPN to connect to the Terminal Server (2003)?  or can you just connect using the TS connectoid without the VPN?
That depends entirely on your corporate firewall. Both Citrix and TS can work with or without a VPN.

Ok.  I up'd the points as well b/c I am getting into  just a little further questions and then I will award.  Thanks.  

So what again, is the difference between or benefit using citrix over and above TS?  Is it that you have control over what users can and can't do?  If so, in general, what can you do through citrix that you can't throu TS?  Is it that you can have more than 1 or 2 people logged on and working at the same time or control what users can or can't do?

Both products allow multiple users, depending on licensing, so it's not really a matter of "how many users".

Also, both products allow you to control what users can or can't do, mostly through group policy. However, Citrix extends this control in a number of ways. As I mentioned earlier, one of my favorites is published applications. This basically allows you to give users access to individual programs, rather than a full desktop session, which in turn simplifies security and limits the user's ability to run things they shouldn't. Terminal Services does allow you to specify a single application for that purpose, but most users require more than one, so that quickly becomes too limiting. You can also specify which users have access to particular applications (using Citrix published apps).

Another major benefit that Citrix has is printing support. Although TS has come a long way, Citrix is much more flexible with supporting different printers, and also has a "generic" driver (they call it "Universal Print Driver" I believe) that works for most other printers that don't have a directly matching driver on the server.

Hope this helps....

"Citrix Presentation Server is not a stand alone product; it requires Terminal Services in Application Mode. This of course means that you not only need Citrix Licenses, but TS CALs (which are, unlike the Citrix licenses, NOT concurrent) as well if you want to use Presentation Server. PS offers enhancements of terminal services, and it has its own protocol, but it still needs the OS to provide the basic terminal services."

Wait a minute...Doesn't Citrix "ICA" do the same thing as terminal svcs?  This is a little confusing as my book seems to imply that you do not need terminal svcs if using ICA.  If you log on using terminal svcs does that not also take the control away from Citrix?  Meaning you can't limit user access to only 2 applications or so with terminal svc's right?  I mean, they pretty much have access to the entire desktop with TS...or do you just give them access to the citrix app through TS and the citrix server handles what they have access to from there?  Please explain.  Thanks.

I think you may be confusing the Programs (Terminal Services and Citrix) with the protocols (RDP and ICA). When installing the Citrix product, it requires Windows Server with Terminal Services enabled in Application mode.  Once everything is installed, by default it has both protocols enabled. This means that, in a basic configuration, you could connect to the server using either an RDP client or Citrix's ICA client. However, if you want to take advantage of the Citrix enhancements (such as published applications), you would only use the ICA client, because the RDP client would not recognize those "advanced" features. Also note that you can configure how many "listeners" are on the server for each protocol, or disable it entirely if you want to force users to use the ICA protocol.

Also note that some of the ways for deploying published applications to users (such as links on a web page), will only work over ICA. RDP does not recognize such links.

Clear as mud, right?  :)

Thanks Technology Works..Getting clearer...Let me make sure I have this right.

The purpose for having TS running on another server in application server mode at the data center is so that the citrix server can connect to the particular application server?

Looks like this?

client workstation using ICA --443--->  INTERNET --443---> Firewall---->Citrix Server--->Terminal Server in App mode-rdp-->File Servers and or app servers

Am I way off or is this a picture of what you are explaining?  Meaning the ICA client sits on the client's workstation and connects into the citrix box.  From there the citrix server must use a terminal services application server to connect to the application or file server?
                                                                                                                                 

No; you install Citrix Presentation Server directly on the machine that has Terminal Services enabled. ICA uses port 1494 by default.

"No; you install Citrix Presentation Server directly on the machine that has Terminal Services enabled. ICA uses port 1494 by default."

Thank you oBdA.  Ok, so you cannot configure the model as I have diagramed.  The TS Server in App mode must be the same physical server as the Citrix Server.  As to the rest of my diagram, does it accurately describe how a typical scenario can work?

"However, if you want to take advantage of the Citrix enhancements (such as published applications), you would only use the ICA client, because the RDP client would not recognize those "advanced" features. Also note that you can configure how many "listeners" are on the server for each protocol, or disable it entirely if you want to force users to use the ICA protocol."

Ok, so if and end user can login to an app server using only a citrix client and only intends to use the CITRIX ICA client and NOT (not shouting just emphasis) RD or Terminal services client to login, then again, it seems strange to me that terminal services is required to be installed on the same server as the citrix server.  This still has not been explained or is unclear to me as to why this is.  Is TS the link between the Citrix Server and the APP/File server?  Meaning WITHOUT it, the Citrix server will not be able to properly connect to the app/file server itself?  Please explain if this definition of the relationship make sense.  Thanks.

I guess my question is:

Does the client machine HAVE to use remote desktop to get into a citrix session and run the apps as if they were on an app server?  Or can they simply use a "citrix" client?  Thx.

hmm.. No that is not my question because you already answered that.  So my question is...

The citrix server has terminal server installed in app mode so that it can talk to the app server right?  I understand that it has to have it installed but trying to understand what it uses it for.

The Terminal Services in Application Mode are required to enable the machine to provide terminal services to begin with. PS doesn't provide the terminal services themselves, it provides a different/enhanced terminal services experience.

Thank you. So bottom line, from the CLIENT experience, you have the full functionality everything by using the citrix (ICA) client?  In my book it says you can use port 443 for the whole session so that it is easier to connect from anywhere, even hotels that may or may not have other ports open..

Yes.

May I ask what book you keep referring to?  

If the default port is 1494, I guess you have to manually change it to 443.  Sure, its called citrix metaframe for windows.  

Correct, the default port is 1494 but can be changed to 443. I'll admit it's been a while since I've done it, but I believe Citrix provides tools for deploying the connection via SSL (port 443), so I don't think it is a _totally_ manual process, but there  is some work involved.

Thanks guys.