The Internet Protocol (IP) is the principal communications protocol in the Internet protocol suite for relaying datagrams across network boundaries. ... IP has the task of delivering packets from the source host to the destination host solely based on the IP addresses in the packet headers.
TCP and IP are two separate computer network protocols. IP is the part that obtains the address to which data is sent. TCP is responsible for data delivery once that IP address has been found.
TCP and UDP are both transport layer protocols. TCP is a connection orientated protocol and provides reliable message transfer. UDP is a connection less protocol and does not guarantee message delivery.
Internet Protocol (IP) In terms of the OSI model, IP is a network-layer protocol. It provides a datagram service between applications, supporting both TCP and UDP.
The OSI model, however, is a proven concept that is used in all other data communications protocols. It will continue to be used as a guideline for all other communications applications.
ISO stands for International organization of Standardization. This is called a model for Open System Interconnection (OSI) and is commonly known as OSI model. The ISO-OSI model is a seven layer architecture. It defines seven layers or levels in a complete communication system.
The OSI (Open Systems Interconnection) model was created by the ISO to help standardize communication between computer systems. It divides communications into seven different layers, which each include multiple hardware standards, protocols, or other types of services.
Transport Layer
ARP works between network layers 2 and 3 of the Open Systems Interconnection model (OSI model). The MAC address exists on layer 2 of the OSI model, the data link layer, while the IP address exists on layer 3, the network layer.
Layer 7 Firewalls (Application Firewalls) Layer 7 lets you sort traffic according to which application or application service the traffic is trying to reach, and what the specific contents of that traffic are.
application layer
FTP is an old protocol. That's really the only reason. The designers thought that the amount of data flowing over the data port would make it so that they couldn't send control commands in a timely manner, so they did it as two ports.
The OSI Model Defined In the OSI reference model, the communications between a computing system are split into seven different abstraction layers: Physical, Data Link, Network, Transport, Session, Presentation, and Application.
port 21
The File Transfer Protocol (FTP) is a standard communication protocol used for the transfer of computer files from a server to a client on a computer network. FTP is built on a client–server model architecture using separate control and data connections between the client and the server.
FTP is a TCP based service exclusively. There is no UDP component to FTP. FTP is an unusual service in that it utilizes two ports, a 'data' port and a 'command' port (also known as the control port). Traditionally these are port 21 for the command port and port 20 for the data port.
80
The most commonly used example is assigning port 8080 for a web server. To get traffic to this web server, you would need to append the port number to the end of the domain name like http://websitename.com:8080. Note that using port 8080 is not reserved for secondary web servers.
Because a UDP packet doesn't require an existing connection, network systems use UDP primarily for broadcasting messages (i.e., a one-to-many sending, much like unsolicited junk email). The most common UDP packets—DNS registrations and name-resolution queries—are sent to port 53.
Examples include Voice over IP (VoIP), online games, and media streaming. Speed – UDP's speed makes it useful for query-response protocols such as DNS, in which data packets are small and transactional.
Netflix, Hulu, Youtube, etc. video streaming all use TCP and simply buffer a few seconds of content, instead of using UDP since the delay is not crucial and TCP transfers can be easily accomplished over HTTP and web browsers without the need for additional plugins and software.
Open firewall ports in Windows 10
Note: Telnet is an application that operates using the TCP protocol. UDP connectivity can not be tested using Telnet.
Malicious ("black hat") hackers (or crackers) commonly use port scanning software to find which ports are "open" (unfiltered) in a given computer, and whether or not an actual service is listening on that port. They can then attempt to exploit potential vulnerabilities in any services they find.
You can test whether the port is open by attempting to open an HTTPS connection to the computer using its domain name or IP address. To do this, you type https://www.example.com in your web browser's URL bar, using the actual domain name of the server, or https://192.