Understanding Port 79: The Finger Service and Its Advantages, Disadvantages, and Security Measures

Port 79 is a TCP (Transmission Control Protocol) port used for the Finger service. This service provides information about a user or a system, including login names, user IDs, and other public information. The Finger service was initially used to look up a user's contact information or to check if someone was online. However, due to security concerns, this service is rarely used nowadays.

How Does Port 79 Work?

When a client connects to port 79, it sends a query to the Finger service. This query includes a username or a hostname. The Finger service then searches its database for information about that user or system and sends a response back to the client. The response can include information such as the user's full name, their office location, and their email address.

Advantages of Port 79

One of the advantages of Port 79 is that it provides quick and easy access to information about a user or system. In the early days of the Internet, when information was not readily available, the Finger service was a useful tool. Additionally, Finger can be used as a troubleshooting tool to check if a user or system is online and available.

Disadvantages of Port 79

One of the primary disadvantages of Port 79 is that it is an unencrypted service. This means that any data sent over the network is sent in plain text, which can be intercepted and read by anyone with access to the network. Additionally, because the Finger service provides a lot of information about a user or system, it can be used by attackers to gather intelligence for a potential attack.

Securing Port 79

To secure Port 79, it is recommended to disable the Finger service altogether. Most modern operating systems do not enable Finger by default, but it is still available on some systems. If you need to use Finger, consider using it over an encrypted connection such as SSH (Secure Shell). Alternatively, you can use a firewall to block all incoming connections to Port 79.

Summary

Port 79 is a TCP port used for the Finger service, which provides information about a user or system. While it was useful in the early days of the Internet, it is no longer widely used due to security concerns. Port 79 is unencrypted, which makes it vulnerable to interception and attack. To secure Port 79, it is recommended to disable the Finger service altogether or use it over an encrypted connection.