They are both data transmission methods for the internet but have different mechanisms. The general protocols used for port scanning are TCP (transmission control protocol) and UDP (user datagram protocol). What are the protocols used in port scanning? Ports 49,151 through 65,536 are dynamic and private ports - and can be used by nearly everyone. Numbers 1024 through 49151 are considered “registered ports” meaning they are registered by software corporations.

Port 80 (TCP) is the World Wide Web HTTP.

Port 53 (UDP) is the Domain Name System (DNS) which translates names to IP addresses.

Port 22 (TCP) holds Secure Shell (SSH) protocol for secure logins, ftp, and port forwarding.

Port 20 (UDP) holds File Transfer Protocol (FTP) used for data transfer.

You may recognize some of the more prominent ports and their assigned services: These ports are held by top-tier companies like Apple QuickTime, MSN, SQL services, and other prominent organizations. They are administered by the Internet Assigned Numbers Authority (IANA). Ports 0 to 1023 are well known port numbers that are designed for Internet use although they can have specialized purposes as well. Ports range from 0 to 65,536 and basically rank by popularity. The port number combined with an IP address form the vital information kept by every Internet Service Provider in order to fulfill requests. Port numbers are used for consistency and programming. Think of it as the parking spot for data to be exchanged through electronic, software, or programming-related mechanisms. Computer ports are the central docking point for the flow of information from a program or the Internet, to a device or another computer in the network and vice versa.

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