If you would like to read the other articles in this series please go to:
- Alternatives to Citrix Presentation Server (Part 2)
- Alternatives to Citrix Presentation Server (Part 3)
Citrix Presentation Server is, for many people, still synonymous with the Server Based Computing technique. Citrix is still market leader in this segment, with a very good product with lots of good features. However nowadays there are several competitors which also have nice products which are more than worthy of consideration. In this article we will take a look at the SBC market and which products are competing with Citrix.
The Server Based Computing technique based on the Windows platform was invented by Citrix. In the early days they licensed Windows NT3.51 and rebuilt this Windows Operating System into the product called Citrix WinFrame. The technique was definitely sensational at that time and became a very popular way of delivering applications to end-users.
Microsoft noticed the popularity and made an agreement with Citrix. This resulted in the release of Microsoft Windows NT4 Terminal Server Edition. Later on Microsoft integrated Terminal Services into the default Windows installation. The Microsoft Terminal Server platform was, and still is, not as feature-rich as the Citrix Presentation Server product. This was reason enough for manufacturers to create add-on products on top of the Microsoft implementation so that it can compete with Citrix Presentation Server.
Let’s take a look at these Citrix alternatives in arbitrary order.
Microsoft Terminal Server
I have already mentioned that mostly every SBC product uses the Microsoft Implementation as the basis for their product, but the Terminal Server component only can also be used in your SBC environment. With Windows 2003 it is only possible to give a Published Desktop to the users. With the new Windows Server version (Windows Server 2008) Published Applications can also be created. Also in 2008, Microsoft will introduce a Web Portal and an SSL secured connection, which are not available right now in Windows 2003. In both versions there is no central management, so settings should be created on every server. Load Balancing is based on the Network Load Balancing protocol so this does not affect the actual load/usage on the server. Most Client mapping options like printer, audio, clipboard are present. Other features are not available in Microsoft Terminal Server.
- Easy installation
- No additional costs (except the default TS Cal)
- Suitable for a smaller environment where only SBC will be used (using a published desktop)
- Almost every thin client has the RDP client built-in
- Limited set of features (also in Windows Server 2008)
- No central management console
- No Published Applications (limited in 2008)
- Very simple Load Balancing technique
HOBLink Enhanced Terminal Services (ETS)
HOB is one of the earliest manufacturers that had entered the SBC market. HOB has several products related to communication to server systems. The first step they made, was adding Terminal Server support in their Java based client. With this client you can also connect to legacy host systems (terminal emulation). Because the client is JAVA based, they support lots of client types like MAC, a lot of UNIX (like) versions, Solaris and Windows.
The real SBC product from HOB is called Enhanced Terminal Services.
From a central console you configure your HOB Farm. You should install the servers manually and the server should be added manually to the farm. There are not many settings that can be configured within the HOB software - it just adds the additional features. The configuration is saved on a web server, network share or on a local disk (so no database support).
Load Balancing is configured per server. HOB has eleven counters that can be used for load balancing. Active sessions, CPU, Memory, Load on NIC, Load on Hard disk are a few examples. All counters can be combined into one load calculation.
HOB has enhanced the local drive mapping feature. Within the console you can specify which directories on the disk are not visible, read only or writable. This feature enhances your security on the local drive mapping.
HOB supports Published Applications and also supports a Published Desktop. With other product/modules the connection can be secured for connection through the internet. The ETS product has not been updated with new features for a while, HOB has focused on other products, like their Blade solution.
- Many client types supported
- Client can also be used to connect legacy host systems
- Enhanced Local Drive Mapping features
- Difficult to pick the products you need
- No Full Seamless Support / No Session sharing
- Relays for maintenance and monitoring on default MS Tools
The history of Propalms goes, just like HOB, back to one of the early players on the SBC market. Originally the product was called Canaveral, but was taken over by Tarantella (called Global Desktop at that time). Sun bought Tarantella, but was not interested in the Windows based product. The Widows product was bought by a British supplier and renamed to Propalms.
The first thing that is conspicuous about the product is the special list of prerequisites. For example the default COM+ (Network DTC access) object needs to be changed and the WMI installation provider is needed (for the remote installation). Also a web server is needed because the client will connect via a portal only. A nice feature is that after the initial installation other servers can be installed with the software from the initial server.
Propalms uses a website as an administration console where all the actions can be performed. If you change something in the configuration a task is created, which is carried out in the background. Users or groups should be added from the Active Directory into the Propalms database to assign settings or applications to those objects. Propalms uses client groups for assigning applications, connection settings and/or printers.
Propalms only supports Published Applications. During configuration Propalms uses the start menu to select your application instead of browsing over the hard disk. There is one load balancer available that applies to all servers which can support a maximum of six (predefined) resource based counters (no user load counter available). Monitoring the environment is mainly possible from the console, which also has a nice reporting set. Other nice options which are included are the ability to add a back-up SQL server, which is synchronized by the Propalms software (so no need for an SQL cluster) and the (free) integration of the Uniprint Universal Printer driver.
There are clients available for Windows, Windows CE, Linux, Mac and some thin client packages. The Windows client installation needs administrative privileges. The option to add applications to a favorite component, the possibility to take over an active application from other workstations and reconnect to disconnected applications are also included. An SSL secured connection is also provided by Propalms.
- Uniprint universal printer product added to the Propalms software (as add-on)
- Good monitoring and reporting functionality in comparison with competitors
- Supported clients and connection option to take over sessions from other client
- Special prerequisite for the COM+ component
- Way the session is initiated (windowed screen) at the client or the downside effect that Windows logon errors are not displayed
- Only one load balancer for all servers.
In this first article we saw how the SBC technique was developed and how Microsoft was involved. After this introduction we described Microsoft Terminal Server features and the first batch of alternatives. In the following articles I will describe more alternatives like Provision Networks VAS, Ericom PowerTerm WebConnect, 2X ApplicationServer and more.
If you would like to read the other articles in this series please go to: