Web-based Applications vs. Applications Hosting with Terminal Services

by Melissa Yang, CTO

I was recently asked about the difference between web-based applications vs. applications hosted with terminal services and decided to share my thoughts with you.  While you may believe that there are no differences, do not be fooled; the differences are very important.

Consider this: When you use eBay, Amazon.com, or other commercial online systems to do business, are you required to download special software onto your computer to use them? No. Why? Because like EscapiaONE, these are web-based applications that you can access from everywhere on virtually any machine in the world.

In contrast, Terminal Services require you to load special software on the machines you wish to use in order to access the systems.

True web-based applications like  EscapiaONE allow secure access from everywhere on virtually any machine seamlessly. All you need is a desktop computer – any computer - with an internet browser.  Terminal services, by comparison, are limited and less sophisticated.

Let’s say that there is a legacy desktop application. Since everyone talks about being on the web, what can you do with it, especially since converting it the right way into a true web-based application will require years of work? The easiest way is to allow multiple users to log into a “hosted” application server with Terminal Services (which doesn’t require any software changes), install terminal services software on each client workstation, and then declare that it has benefits of a web-based solution, except that it doesn’t.

For property managers, here is why a terminal service solution is not a viable solution for you:

• Not Convenient.  You will not be able to use Terminal Services from anywhere on any machine, since it requires installing some specific client software for different operating systems (instead of just an Internet browser).  You will have to bring your specific machine with you whenever and where ever you wish to use it. 
• Not Reliable.  To use a terminal service application, you have to log on explicitly to a single server.  If it is down, you have to log on to another server (this is assuming that there are multiple servers set up, which is not always the case given complicated user management involved).  Instead of just a URL, you will need to remember a list of server addresses and try them one by one.  It is a clumsy and manual process.  In contrast, with true web-based solutions, there are usually multiple servers to serve web pages simultaneously.  If one server becomes slow or is down temporarily, you will be routed to another server automatically.  It is so seamless that you won’t even notice it.   
• Slow and Expensive.  Unlike true web-based solutions, terminal services don't scale with the number of users.  To support the same number of users, more servers are needed by terminal services than a web-based solution.  Also, adding users requires you to buy additional memory on a server as well as additional licenses (a Client Access License and a Terminal Services Client Access License).  See cost details here.  Those additional costs will surely be passed on to you.  Finally, since multiple users use the same server, long operations performed by one user will impact other users on the same server resulting in deteriorated performance when more users use the same server simultaneously.    
• Same Disadvantages of Desktop Applications.  A big issue with desktop applications is the high cost of installation and maintenance.  Terminal services are essentially the same thing with the only difference being that multiple users can run an application on a remote server.
• Terminal services are not Secure.  In true web-based solutions, the servers are well protected behind firewalls and only administrators can access them.  In the case of Terminal Services, each user is able to access and use a server directly. 

The fundamental differences between Web-Based applications and Terminal Services are in the connectivity, performance, and security.  Web-based solutions have centralized servers and end users can use them from everywhere on virtually any machine.  Terminal Services is an old, antiquated desktop model that existed long before Web 2.0 world and is being used less and less because of its limitation and costs.