Week 6 - Firewalls and Web Proxies

We often hear about firewalls on Windows systems and get a general idea of what they do, but how exactly do firewalls relate to general infrastructure and hardening? Well, Firewalls use explicit rules that control how they handle traffic. In a lot of cases, the default settings for these firewalls tend to deny all incoming connections and allow all outgoing connections. That means that anyone attempting to reach your machine will be unable to connect, while outbound attempts from the same machine will be able to reach outside connectivity. Sometimes, firewalls do not have a default configuration and when this happens, there needs to be baseline rules set up.

Now what about web proxies? A web proxy is a system that intercepts and then forwards web traffic between clients and servers. These proxies are most commonly used to carry out content filtering to ensure that the acceptable-use policy is being met by the organization. They can block out any unacceptable web traffic and not only block the traffic, but have lots of information such as who visited the website, bandwidth, block restricted website usage, and filter out specific keywords. Proxy servers can also be configured to act as caching servers, which keep local copies of frequently requested resources, enabling organizations to significantly reduce their upstream bandwidth usage and costs while significantly increasing performance.