5.2.3 Network Ports

Directions: Type the correct word to complete the sentence. When your computer is part of a network, it's moving a lot of information very quickly. The network needs to have rules, or protocols, to help guide the traffic so it gets to the right place. Just like the post office accurately delivers your mail by reading your street address and postal code on the envelope, network traffic is easier to manage with network identifiers such as IP addresses and ports.Network ports are unique numbers that the operating system assigns to different types of network traffic. They work like parts of a mailing address, sending deliveries to specific places. Port numbers help to direct the information on a network, depending on what kind of information it is. For example, when you send an email to your co-worker, the bundle of data includes the port number 587. It's like a special ticket that sends the data to a corresponding port on your co-worker's computer.Some port numbers are reserved for the most common services, like email or for transferring files. Other services get a port number only when they're in use. Once that service is done using the port, the number goes back to being unassigned. Some types of ports are turned off. Just as warehouse doors can be opened or shut, closed ports mean you cannot enter.Port ForwardingPort forwarding is like telling a letter carrier to send your mail to a new address if you're not at home. You would still want to receive your information, even if you were at a different location. That's essentially what you're telling the router or firewall to do with the packets of information when you use port forwarding.A common port for this is port 3389, used for theremote desktop protocol (RDP)on agraphical user interface (GUI). This basically lets you connect to any other Windows computer anywhere in the world!To make this happen, you have to set things up correctly on both computers and the internet router, which is a bit like making sure both doors are unlocked and open so you can walk through. Port Forwarding Directions: Match the port number to the name. 21 File Transfer Protocol (FTP) 22 Secure Shell (SSH) 23 Telnet 25 Simple Mail Transfer Protocol (SMTP) 53 Domain Name System (DNS) 80 Hypertext Transfer Protocol (HTTP) 110 Post Office Protocol version 3 (POP3) 143 Internet Message Access Protocol (IMAP) 443 Hypertext Transfer Protocol Secure (HTTPS) 587 Simple Mail Transfer Protocol (SMTP) Port Forwarding Directions: Match the port name to the definition. File Transfer Protocol (FTP) Standard protocol used for moving files between computers Secure Shell (SSH) Provides for secure communication between devices Telnet Provides for unsecure communication between devices Simple Mail Transfer Protocol (SMTP) Used for sending email. However, it has been deprecated in the last decade Domain Name System (DNS) Provides a translation between friendly domain names and IP addresses Hypertext Transfer Protocol (HTTP) Provides communication standards for clients and servers on the World Wide Web Post Office Protocol version 3 (POP3) Used by email programs for incoming email Internet Message Access Protocol (IMAP) Used most commonly for receiving email Hypertext Transfer Protocol Secure (HTTPS) Establishes encrypted communication between clients and servers on the World Wide Web Simple Mail Transfer Protocol (SMTP) Used for outgoing email