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Frequently Asked Questions

Here are some commonly asked questions about Liberator and the Free Liberator project. If you have a question that is not answered here, why not post a question on the forum? The creators of Liberator are regularly online and happy to help.

What is Liberator?

Liberator is a very efficient server for real-time information. Using common internet technologies, it effectively bypasses proxies and delivers streams of information to anyone with a browser and a connection to the internet. It is written in a low-level language so performs very efficiently.

Who makes Liberator?

It has been developed by Caplin Systems for several years and is used by many well-known financial institutions. It is relied upon daily for large transactions in real-world trading scenarios.

Why are you giving it away for nothing?

Because we want to make it as easy as possible for people to evaluate, and because we want to increase its popularity by making it free to use in non-commercial applications.

How do I get Liberator Free Edition?

Follow this link.

What is new in Liberator 4.5?

In this version we have increased the range of browsers that work with Liberator and upgraded the connection types. This means an end to 'always loading' messages in the browser. You will need a new license to use the updated version - you can get one from the downloads page.

Is Liberator Free Edition limited in any way?

The Free version is the same software we provide to our paying clients. The major difference is that we do not include our advanced APIs for .NET, C/C++ and Java. Authentication permissioning is also disabled as is enterprise-level JMX monitoring. See the feature comparison for more details.

Why doesn't my license work with the new download?

The new download is a minor version upgrade. This means that the license file has different contents and requires a new key to validate those contents. Get a new license from the downloads page - it's free!

Why do I have to register to use Liberator?

We would like to know who is using our product for marketing and tracking purposes. We will not release your data to any third parties or send you any email junk. Privacy Policy

Do you offer support?

Since this is not a commercial release, we are not offering support for Liberator Free Edition. There is a forum which is monitored by our team. If you would like to talk to us about our full range of services, including support, please follow this link and leave your details on our website.

What is SL4B?

SL4B stands for StreamLink For Browsers. It is the name for the system we have created enabling real-time data display across browsers.

What is RTTP?

RTTP is the protocol used by Liberator to transmit information to the browser. It works in a similar way to http and is thus able to effectively bypass proxies and firewalls.

What is RTML?

RTML is a simple markup language you can use to create pages containing real time data. It wraps around SL4B, allowing you to access the power of Liberator with minimal investment of time.

What is DataSource?

DataSource is the name for the component which provides data to Liberator.

Can I run Liberator Free Edition on Windows?

Yes! You can run it in a virtual Linux machine. We have created a VMware appliance, designed to run on Windows. Download the appliance from the downloads page and then download the free VMware Player. Follow the getting started guide for Windows and you should have a working Free Liberator server pretty quickly.

What is a VMware Appliance?

It is a prebuilt environment designed to run under VMware and to run a specific set of software. It allows software developers to preconfigure a 'Virtual Machine' to run their product. In our case it means that Liberator can be run on Windows, or in fact any OS platform that runs VMware.

Why does my Appliance have no IP address?

Fix first: reboot your appliance and it probably will have. Cause second: this is most likely to be the VMware DHCP server taking a long time to respond with an address. If a reboot of the appliance doesn't fix the problem, there is something wrong with your VMware network setup. Send us a message on the forum and we will try to help.

Where can I find more information about Comet?

The 'What is Comet?' page gives a brief overview of Comet. If you would like to read more about Comet you can find lots of information at CometDaily and Wikipedia.

Why isn't Liberator written in Java, so I could just run it in a JVM?

One of the design goals of Liberator was to achieve the highest possible messaging performance. Memory-managed high-level languages like Java were not designed for real-time applications, and limit performance while making deterministic control of message latency almost impossible. In contrast, the C language is much closer to machine code and is ideal for this purpose, allowing very precise and efficient management of processing and I/O.

Why doesn't Liberator run native on Windows?

Liberator is used in demanding, business-critical applications, mainly in finance, in environments where Unix is almost ubiquitous and Windows servers are rarely used. Because the Windows I/O model is very different from the Unix model, a rewrite of Liberator would be required to make it run on Windows. Fortunately the performance in a VMware Appliance (see above) is very good so this is not necessary.

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