What is SOCKS Proxy?
A SOCKS proxy is a server that uses the socket secure protocol to route traffic through itself in order to bypass firewalls. The proxy itself establishes a three-way connection between the web client and the server. A SOCKS proxy achieves this by creating a Transmission Control Protocol connection that acts as a path through which data packets are sent.
How SOCKS Proxies Work
Although it helps bypass firewalls, SOCKS proxy, also known as SOCKS4 proxy, has several limitations. For example, it doesn’t support authentication, which means it lags behind in terms of security. Second, it does not support User Datagram Protocol (UDP), a fourth-layer protocol that helps manage internet traffic and communication between a web server and a client like TCP. This second limitation means that SOCKS4 proxies cannot easily distinguish between requests that are routed through them. Solution: SOCKS5 proxy.
The SOCKS5 proxy supports authentication and UDP. The latter improves efficiency because UDP sends datagrams (messages), a better communication mode than the individual data packets sent by TCP. Although UDP does not guarantee data delivery, it can perform verification to ensure data integrity. Second, UDP assigns port numbers that help distinguish between different user requests. SOCKS5 proxies initiate communication over TCP and then send messages over UDP.
Features of SOCKS Proxies
SOCKS proxies have the following features/features:
- SOCKS and SOCKS5 proxies support different types of requests and protocols, including HTTP, HTTPS, FTP, POP3, and SMTP.
- They are flexible because they don’t rely on just one protocol
- They can handle higher volumes of internet traffic (because they can handle multiple request and protocol types)
- SOCKS5 proxies support authentication
- SOCKS proxies send data via Transmission Control Protocol (TCP), while SOCKS5 proxies send data via TCP and User Datagram Protocol (UDP).
- SOCKS proxies are extremely fast, especially when they don’t handle a lot of protocols/requests
- They do not provide encryption natively, except when they use the HTTPS protocol
- SOCKS5 proxies include headers that include the user’s personal information
- They forward web requests as they are received (SOCKS proxies do not interpret web traffic)
Use of SOCKS Proxies
SOCKS proxies are used to:
- They provide access to data behind the firewall
- SOCKS proxies are used to stream web content (video, music and data).
- File sharing using peer-to-peer methods due to File Transfer Protocol (FTP).
- Email sending thanks to SMTP (Simple Mail Transfer Protocol) and Post Office Protocol 3 (POP3) support
- A general web browser as it supports HTTP and HTTPS
- Restricting access to servers to clients only: this use case relies on SOCKS proxies supporting authentication. Thus, commercial service providers can use various authentication methods supported by these proxies to ensure that only their subscribers or customers can access their servers.
In this regard, SOCKS proxies are used by companies operating in the file sharing, emailing, and streaming (music and video) industries.
SOCKS and HTTP Proxy
Interestingly, there is another type of proxy known to use a protocol such as SOCKS proxies. An HTTP proxy is an intermediary designed to handle Hypertext Transfer Protocol (HTTP) requests. (But unlike SOCKS proxies, which can handle many types of requests—HTTP, HTTPS, SMTP, POP3, and FTP—HTTP proxies can only handle HTTP requests.
An HTTP proxy can be configured to forward HTTP requests just like client-side proxies. Alternatively, it can be configured to accept HTTP requests as with server-side proxies. Together, both client-side and server-side HTTP proxies are known as content filtering tools. This is because it can interpret data contained in HTTP requests or responses.
Compared to SOCKS proxies, HTTP proxies are slower. Moreover, the latter type also handles less traffic than the former because HTTP proxies only handle HTTP requests, while SOCKS proxies can handle HTTP, HTTPS, SMTP, POP3, and FTP proxies. Meanwhile, SOCKS proxies use Transmission Control Protocol (TCP), while HTTP proxies ignore it.
The result
SOCKS proxies are flexible. So companies in a variety of industries, including streaming, email, and file sharing, can use them. This flexibility comes from the fact that SOCKS proxies can deliver data using a number of protocols, including HTTP, HTTPS, FTP, POP3, and SMTP. Additionally, SOCKS proxies can be used to bypass firewalls. For a more in-depth look at the difference between SOCKS and HTTP proxies, see this blog post.