Web server
A web server responds to browser requests using standard web browsing protocols of HTML or HTML5. Web pages are stored on the server. The browser on your computer requests for the web pages on the server. The data is then downloaded to your browser. These can be static pages or pages that are built dynamically in real time.
File server
A file server provides a centralized storage for documents and files. The file server will use a standard system of file management such as SMB (Server Message Block) on Windows, Apple Filing Protocol (AFP) on MacOS, etc. The front end of the file server hides the protocol being used. The user simply uses the File Manager that they see on their operating system. The protocols between their computer and the file server handle all the transactions such as copying, deleting, renaming files, etc.
Note that a file server is not the same as an FTP server. An FTP server is accessed via an FTP client software and is more for accessing files across the Internet. A file server is usually within your private network.
Print server
A print server is used to connect a printer (or printers) to the network. A print server provides printing services for all network devices. The print server acts as a middle man between someone requesting to print and the actual printer. A print server can be software in a computer connected to the printer or it can be built into the printer.
Printing with a printer server uses standard printing protocols such as SMB (Server Message Block), IPP (Internet Printing Protocol), and LDP (Line Printer Daemon)
DHCP server
DHCP stands for Dynamic Host Configuration Protocol. DHCP is protocol responsible for providing automatic IP address configuration for all clients that plug into the network. A DCHP server is available on most home routers. In an enterprise, you’ll probably find multiple DHCP servers running for redundancy.
A DHCP server helps to ensure there are no duplicate IP addresses on the network.
DNS server
DNS stands for Domain Name System. DNS converts names to IP addresses and vice versa. For example, you don’t need to know the IP address of Google’s website, you can simply type in www.google.com. The DNS server was responsible for translating google.com to its associated IP address. DNS is a distributed naming system. There are thousands and thousands of DNS servers on the Internet. A DNS server is usually managed by the Internet Service Provider. An enterprise that has their own internal service most likely will have their own DNS servers in their data servers. That’s why when you look at the DNS configuration settings on your operating system, there will usually be at least 2 slots to enter DNS server IP addresses.
Proxy server
A proxy server acts as an intermediate server. A client on the network makes a request to the proxy. The proxy performs the actual request and then provides the results back to the client. Organizations can use a proxy server for all of their internet communication. A proxy server is useful to perform access control, caching, malware scanning, URL filtering, content scanning, etc.
Mail server
A mail server stores your incoming mail and sends your outgoing mail. Mail servers are usually managed by your Internet Service Provider (ISP) or your organization may have their own mail servers.
Authentication server
An authentication server provides login authentication to resources. The authentication server is a centeralized repository of all of the authentication credentials for your organization. When you log in to your enterprise computer or VPN, your credentials are sent to the authentication server for verification. An authentication server is not generally used on home networks. Authentication servers in a corporate environment are usually redundant to maintain availability. Authentication servers are usually spread across multiple servers.
Syslog
Syslog is the standard for message logging. Syslog requires a large amount of data space to store all of its information. Syslog is the means by which devices can report their logs and events to a SIEM (Security Information and Event Management), which gathers logs from a variety of devices and events. Some syslog tools use WORM drive technology which means to write once read many. This would be things like optical drives where you write data to it once and can read the information from it many times.