Reverse proxy Definition
When I first started to tell people about my new job with section.io, I often was asked “What is a reverse proxy”? To be honest, I had actually googled the same question. I was familiar with proxies, but wasn’t entirely sure what the difference was between a proxy and a reverse proxy.
This confusion comes from people dropping the term “forward” from forward proxy. There are forward proxies and reverse proxies, both of which are different types of proxies. By dropping “forward” from forward proxy, people ask what is the difference between a proxy and a reverse proxy, when really (using correct terminology) a reverse proxy is a type of proxy and the intended question is what is the difference between a forward proxy and a reverse proxy. Let’s briefly discuss these three concepts.
A proxy, in the context of the internet, is a server that your web requests go through. This makes sense as the definition of a proxy from the dictionary is one who acts for another. The difference between a reverse proxy and a forward proxy is who or what they act on behalf of.
A reverse proxy acts on behalf of your web server, taking requests from externally (ie. your customers) and determining how they should be handled. A WAF (web application firewall) which as Modsecurity will handle a request by auditing or blocking the request. A web accelerator such as Varnish will handle a request by trying to answer with cached information.
A forward proxy acts on behalf of clients. A common use case is taking requests from internally (ie. a local network in an office) and determining how they should be handled. For example, the devices within an office may not directly connect to the internet, they may first connect to a forward proxy who then connects the requests to the internet. This allows for a system administrator to decide which content should be allowed into the network, which provides both content filtering and security.
At its core, section.io is a reverse proxy management platform that allows our users to easily add globally distributed reverse proxies and gain visibility into the impact they have on their web servers. If you are interested in seeing how a reverse proxy might work for your website, trial section.io free for 14 days.