Internet Protocol (IP)
The Internet Protocol (IP) is a fundamental communications protocol within the Internet protocol suite, commonly referred to as TCP/IP, which underpins internet connectivity and data exchange. IP is responsible for the transfer of data between computers over the Internet, utilizing a routing system to direct packets of information efficiently. There are two primary versions of IP in use today: Internet Protocol version 4 (IPv4) and version 6 (IPv6), with IPv4 being the most widely adopted due to the gradual transition to IPv6. Each device on the Internet is assigned a unique IP address, which comprises a network address and a specific device identifier within that network.
Data is transmitted across the Internet in small packets known as "datagrams," each containing a header with the sender's and receiver's IP addresses, as well as a payload representing the actual message content. The routing of these datagrams involves multiple gateways that read destination addresses and forward packets accordingly. Importantly, IP is considered an unreliable service, as it does not maintain a continuous connection and allows for packets to take different routes, potentially arriving out of order. To address this, the Transmission Control Protocol (TCP) works alongside IP to ensure that datagrams are reassembled in their original sequence upon arrival, enhancing the reliability of data transmission. Understanding IP is crucial for grasping how the Internet facilitates global communication and information exchange.
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Internet Protocol (IP)
The Internet Protocol (IP) is the main communications protocol of the internet protocol suite (commonly called the TCP/IP), the networking model that establishes the internet. A network enables the exchange of information, while a protocol is a set of conventions for formatting communications data. The IP is the method by which data is transferred between computers via the internet. Thus, its routing system, or system for directing, is what makes the internet a place for exchanging information.
Overview
Two versions of the Internet Protocol are in use: four (IPv4) and six (IPv6). IPv4 is the most common, as nations have been slow to adopt IPv6. Each computer connected to the internet has an IP address, a set of numbers that uniquely identify the computer. IPv4 addresses consist of 32 bits of digital space, while IPv6 uses 128-bit addresses. There are two parts to the address identification: the specific computer network and the specific device within that network. On the internet itself, between routers that move packets of information, only the network address needs to be accessed. Both pieces of information are necessary for sending the message from a network point directly to a computer.
When data such as a website page or an email is sent via the internet, the message is divided into packets called “datagrams.” Each datagram is composed of a header and a payload. The header contains the source (sender) and destination (receiver) IP addresses, each of which include the computer’s unique network and device addresses, and other metadata needed for routing and delivering the packet. The payload is the message data itself.
The datagram is first sent to a gateway computer—a network point that functions as the entranceway to another network—which reads the destination address and forwards the message to the next gateway. This gateway reads and forwards the address to yet another gateway, and so on, until the message reaches the closest gateway to its destination. The last gateway recognizes the datagram’s address as belonging to its domain, or the set of network addresses under its control, and forwards the message directly to the final device destination.
IP routing service is considered unreliable because of the dynamic nature of the internet and the possibility that any network element may also be unreliable. Therefore, the Internet Protocol has no continuing connection between end points. Each packet of data is treated independently of all other packets of data. Individual datagrams may not necessarily travel the same route across the internet, as they are trying to get past any errors along the way, and they may arrive in a different order than they were sent. The IP is just a delivery service, so another internet protocol, the Transmission Control Protocol (TCP), reorganizes the datagrams into their original order.
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