Windows 7 Simple TCP/IP Services - What and How?

What are Simple TCP/IP Services?

Simple TCP/IP Services are really a collection of command line utilities. This collection includes the "quote of the day" protocol, the daytime protocol, character generator (chargen), echo protocol, and discard protocol.

Really, these are just ports that are opened up on your Windows computer to perform specific testing or diagnostic functions. These aren't going to be used by any program that I have ever seen nor are they something that you are going to use every day.

Let's run down each one of these protocols / services and explain what each one does (according to Microsoft TechNet):

Quote of the Day (QOTD) - based on RFC 865 - uses port 17 - Returns a quotation as one or more lines of text in a message. Quotations are taken at random from the following file: systemroot\System32\Drivers\Etc\Quotes. A sample quote file is installed with the Simple TCP/IP Services. If this file is missing, the quote service fails.

Here is what I get when I do a-

telnet localhost 17

Figure 1

Daytime - based on RFC 867 - uses port 13 - Returns messages containing the day of the week, month, day, year, current time (in hh:mm:ss format), and time-zone information. Some programs can use the output from this service for debugging or monitoring variations in system clock time or on a different host.

The results of telnet localhost 13 are-

Figure 2

Character Generator (chargen) - based on RFC 864 - uses port 19 - Sends data made up of the set of 95 printable ASCII characters. Useful as a debugging tool for testing or troubleshooting line printers.

If you type telnet localhost 19 you will get-

Figure 3

And, you will have to press CTRL-], then type quit to get the manic scrolling of characters to stop (or kill your command line).

Echo - based on RFC 862 - uses port 7 - Echoes back data from any messages it receives on this server port. Echo can be useful as a network debugging and monitoring tool.

Typing telnet localhost 7 will get you-

Figure 4

Really, this is just echoing anything that you type back to you.

Discard - based on RFC 863 - uses port 9 - Discards all messages received on this port without response or acknowledgment. Can serve as a null port for receiving and routing TCP/IP test messages during network setup and configuration or, in some cases, can be used by programs as a message discard function.

Telnetting to the discard port (port 9) will give you NO response as this is a NULL port and everything sent there is discarded.

How do you turn on or off the Simple TCP/IP Services?

To turn off (enable) simple TCP/IP services, you just need to go into Control Panel, to Programs, then to Turn Windows Features on or off. You do not need to install any applications.

From here, click on the checkbox for the Simple TCP/IP Services, as you see in the graphic below.

Figure 5

It will take just a few seconds to install these services.

Figure 6

Once installed, you will just be brought back to the Programs window. There is no indication that they were successfully installed. Once the simple TCP/IP services are installed you cannot enable or disable individual services. In other words - "it's all or nothing".

If you want to start using these services right away, you will have to go into your Services MMC / console and Start the service.

The service is labeled as automatic so it will start upon your next reboot but you must start them manually if you aren't going to reboot (a reboot is not required).

Figure 7

How do you disable the services? Simple, just do the opposite of what I just did. You should Stop the service, then go in and uncheck the checkbox in the Windows Features list. This will disable and uninstall the Simple TCP/IP Services.

How can the Simple TCP/IP Services help you?

Today, the simple TCP/IP services have limited use. Here are a couple ideas that I came up with:

1. Learning - these services have their roots in Linux / Unix and have been around for a long time. Perhaps you are taking a Windows test where you feel you need to know all the networking features. Perhaps you are just curious and want to gain experience in all the possible TCP/IP networking features & protocols. Either way, it only takes a second to learn about the simple TCP/IP services and try them out for yourself.
2. Testing - Perhaps you want to enable this on a machine that is, say, inside a firewall then test opening ports to that machine.

No matter your use in enabling these services, honestly, I would recommend that you disable when you are done as any open ports could become security risks.