Radio Silence - Simple and Cheap Little Snitch Alternative
A firewall is a device that is designed to permit or deny network transmissions based upon a set of rules. When we talk about a regular run-of-the-mill home network you have two firewalls, your router and the firewall built into your OS. The Mac OS has a software based firewall that prevents traffic from entering your computer from the outside. Radio Silence on the other hand prevents applications from sending traffic out.
So why would you want to block applications from accessing the internet? Well the main reason is a bit of a naughty one, mainly to prevent applications from de-authenticating borrowed software keys. Applications like Little Snitch and now Radio Silence have been used for a long while to prevent applications from going to the internet to authenticate a software key that might not be so authentic anymore.
There are other practical reasons you would want to monitor network traffic, mainly for security. Controlling what applications have internet access can prevent applications from doing naughty things they shouldn't be doing. It's a good way to prevent applications from relaying information they shouldn't. Little Snitch vs. Radio Silence
For a while now Little Snitch has been the best Mac Application that could monitor outgoing traffic. It's very good at what it does but the application costs $29 and has popups that force you to okay every outgoing network connection, which can get annoying. Radio Silence on the other hand is only $9 and will never have popups is super lightweight and easy to manage.
There are some major differences between the two. The biggest difference is Little Snitch Blocks everything, while Radio Silence only blocks applications you add to the block list. So from a security standpoint Little Snitch is better because you don't have to know about the application in order to block it's internet access. The other main difference is that Little Snitch allows you to choose which ports to block which gives you the ability to allow the application access to ports it might need to function properly.
If you are looking for a comprehensive tool for monitoring outgoing network traffic and want the ability to customize port access for very application and process on your computer than you should go for Little Snitch. If you just need to deny internet access to specific applications and don't want the headache of dealing with all the permissions for every application then Radio Silence is the app for your. Check them both out with the links below. Little SnitchRadio Silence Update 08/19/2011 11:56
If you want a completely free piece of software that does something similar to both Radio Silence and Little Snitch then give TCBBlock
a try. It has a system preference pane to control the block list and seems to land somewhere between Little Snitch and Radio Silence as far as features are concerned.