I would say the closest alternative to Outpost Firewall is
COMODO Firewall - in fact, COMODO Firewall is considered by many to be Outpost Firewall's rival software.
As of version 8.2, COMODO Firewall incorporates the following security components:
- Firewall Network firewall which monitors packet transactions through network protocols and can be configured to either automatically handle network events or prompt the user with an alert to handle the event by allowing or blocking the action. In the case of the event being triggered by the attempted action of a running process, the user may or may not be prompted with an alert (based on CFW's configuration) to allow that action, to block that action, or to treat the process' action based on a predefined ruleset. The user can also optionally have CFW create a rule for his specific choice in that particular alert, so that every next time the same event is triggered, CFW resolves it automatically based on that choice of the user.
- Defense+ (HIPS) Defense+ is the name of COMODO Firewall's HIPS (Host Intrusion Prevention System) component, which monitors process and local system activity within the host and prompts the user for any suspicious event, based on specified monitoring settings in COMODO Firewall's configuration. The rest is the same as in the case of the network Firewall: The event is either handled automatically based on COMODO Firewall's configuration or the user is prompted to act with an alert which contains the same types options as the alerts of the network Firewall. (allow the action, block the action, treat the action based on a ruleset, and optionally store the user's answer to the alert so that the chosen option is automatically applied the next time the same event is triggered)
- Sandbox The COMODO Sandbox component (technically a part of Defense+) allows for the "virtualization" of the actions of specified target processes, so that those actions are redirected to a virtual area which is intended to mimic the functions of the actual system, using proprietary virtualization routines. In this way, the actions of sandboxed processes (which are usually suspicious) do not affect the physical system, rather the virtual "container" which imitates the actual system. Sandboxed processes function completely normally (in the vast majority of cases), and their actions csn be immediately erased by the user through the related COMODO Firewall option. Sandboxed processes cannot access the files, data, and running processes of the physical system, as their actions are being redirected to the virtualized system within the sandbox. COMODO Sandbox can be configured to automatically sandbox processes based on a group of policies predefined within COMODO Firewall's configuration. The user can also configure policies which will instruct COMODO Sandbox to alert the user instead of automatically applying the rules of a specific policy. With these alerts, the user will be prompted to choose whether to run the process sandboxed, un-sandboxed, or to block the process' execution altogether. COMODO Sandbox can also be configured with custom policies to impose certain levels of restrictions on sandboxed processes, so that in addition to their actions being redirected within the sandbox, some of their action which require elevated privileges (permissions to perform critical system actions) are completely blocked.
- Viruscope The Viruscope component of COMODO Firewall (also technically part of Defense+) by default actively analyzes the actions of sandboxed processes (can also be configured to analyze specific groups/types of non-sandboxed applications) and determines whether those processes might be malicious or not. Then, Viruscope prompts the user with an alert, in which the user can choose to block or ignore that process, and, if blocked, the user can choose whether to have Viruscope attempt to revert that process' actions or not. Viruscope can of course, like any other component of COMODO Firewall, be configured with certain policies which outline how it should function.
I'm sorry about the wall of text, however I wanted to make this post as encompassing as possible.
If you want to have a more thorough read on the components of COMODO Firewall and their function, be sure to check out the following official help guide pages:
COMODO Internet Security v8.2 Help Guide
COMODO Internet Security Help Guides [List of help guides for all versions]
COMODO Internet Security incorporates all COMODO Firewall components, with the addition of COMODO Antivirus. Therefore, the above guides also apply to COMODO Firewall, minus the pages covering COMODO Antivirus, of course.
The current version of COMODO Firewall/COMODO Internet Security at the time this message was posted, is version
8.2. The second link above is an index of guides for every version of CFW/CIS, and that is where you will find links to the latest help guides for future versions as well.
That would be all as far as COMODO Firewall is concerned.
The only drawbacks to this program are certain glitches/bugs (which affect mostly the usability of the application), the need for configuring the various components for optimal security, and the fact that it requires from its users, at least a medium level of knowledge in computers or in IT in general due to the potentially technical nature of its components, its alerts and/or its configuration options.
Other than that, I believe that in the hands of a sufficiently experienced user, combined with proper configuration and safe computing habits, COMODO Firewall can provide an unparalleled level of protection and security.
In other words, I am confident that COMODO Firewall can be a more than satisfactory substitute for Outpost Firewall.
Another similar security product is
Privatefirewall by
Privacyware, for which however I cannot provide substantial input, as I have never used it beyond testing it in a virtual machine.
Judging from the multiple tests I conducted on Privatefirewall however, I am inclined to believe that it could also be worth looking into.
I hope you find this information of use!
EDIT: The network Firewall component of COMODO Firewall also allows the user to define network zones (e.g. domain names, IPs, IP ranges, etc) to be blocked.