Transmission Control Protocol AND Internet Protocol

 

TCP(Transmission Control Protocol) AND IP(Internet Protocol)

BY- PRADEEP D

ABISWARAN M

 

REVIEWED BY-

Dr. C. R. SAKTHIVEL MCA., M.Phil., Ph.D.,

              

What is Transmission Control Protocol (TCP)?

TCP (Transmission Control Protocol) is one of the main protocols of the Internet protocol suite. It lies between the Application and Network Layers which are used in providing reliable delivery services.

 

In this article, we will discuss about Transmission control protocol in detail. We will also discuss IP, the Difference between TCP and IP, and the working process of IP here. Let’s proceed with the definition of TCP First.

 

Transmission Control Protocol is a connection-oriented protocol for communications that helps in the exchange of messages between different devices over a network. The Internet Protocol (IP), which establishes the technique for sending data packets between computers, works with TCP.

 

The position of TCP is at the transport layer of the OSI model. TCP also helps in ensuring that information is transmitted accurately by establishing a virtual connection between the sender and receiver.

 

Working of Transmission Control Protocol (TCP)

To make sure that each message reaches its target location intact, the TCP/IP model breaks down the data into small bundles and afterward reassembles the bundles into the original message on the opposite end. Sending the information in little bundles of information makes it simpler to maintain efficiency as opposed to sending everything in one go.

 

After a particular message is broken down into bundles, these bundles may travel along multiple routes if one route is jammed but the destination remains the same.

 

 

For Example: When a user requests a web page on the internet, somewhere in the world, the server processes that request and sends back an HTML Page to that user. The server makes use of a protocol called the HTTP Protocol. The HTTP then requests the TCP layer to set the required connection and send the HTML file.

 

Now, the TCP breaks the data into small packets and forwards it toward the Internet Protocol (IP) layer. The packets are then sent to the destination through different routes.

 

The TCP layer in the user’s system waits for the transmission to get finished and acknowledges once all packets have been received.

 

 

 

 

 

 

 

Advantages of TCP

·     It is a reliable protocol.

·     It provides an error-checking mechanism as well as one for recovery.

·     It gives flow control.

·     It makes sure that the data reaches the proper destination in the exact order that it was sent.

·     Open Protocol, not owned by any organization or individual.

·     It assigns an IP address to each computer on the network and a domain name to each site thus making each device site to be distinguishable over the network.

 

IP (INTERNET PROTOCOL)

 

IP stands for internet protocol. It is a protocol defined in the TCP/IP model used for sending the packets from source to destination. The main task of IP is to deliver the packets from source to the destination based on the IP addresses available in the packet headers. IP defines the packet structure that hides the data which is to be delivered as well as the addressing method that labels the datagram with a source and destination information.

 

An IP protocol provides the connectionless service, which is accompanied by two transport protocols, i.e., TCP/IP and UDP/IP, so internet protocol is also known as TCP/IP or UDP/IP.

The first version of IP (Internet Protocol) was IPv4. After IPv4, IPv6 came into the market, which has been increasingly used on the public internet since 2006.

History of Internet Protocol

The development of the protocol gets started in 1974 by Bob Kahn and Vint Cerf. It is used in conjunction with the Transmission Control Protocol (TCP), so they together named the TCP/IP.

The first major version of the internet protocol was IPv4, which was version 4. This protocol was officially declared in RFC 791 by the Internet Engineering Task Force (IETF) in 1981.

 

After IPv4, the second major version of the internet protocol was IPv6, which was version 6. It was officially declared by the IETF in 1998. The main reason behind the development of IPv6 was to replace IPv4. There is a big difference between IPv4 and IPv6 is that IPv4 uses 32 bits for addressing, while IPv6 uses 128 bits for addressing.

 

What is an IP packet?

Before an IP packet is sent over the network, two major components are added in an IP packet, i.e., header and a payload.

 

·      Source IP address: The source is the one who is sending the data.

·      Destination IP address: The destination is a host that receives the data from the sender.

·      Header length

·      Packet length

·      TTL (Time to Live): The number of hops occurs before the packet gets discarded.

·      Transport protocol: The transport protocol used by the internet protocol, either it can be TCP or UDP.

·      There is a total of 14 fields exist in the IP header, and one of them is optional.

 

What is IP Addressing?

An IP address is a unique identifier assigned to the computer which is connected to the internet. Each IP address consists of a series of characters like 192.168.1.2. Users cannot access the domain name of each website with the help of these characters, so DNS resolvers are used that convert the human-readable domain names into a series of characters. Each IP packet contains two addresses, i.e., the IP address of the device, which is sending the packet, and the IP address of the device which is receiving the packet.

 

Types of IP addresses:

·      Public address

·      Private address

 

Public address:

 

The public address is also known as an external address as they are grouped under the WAN addresses. We can also define the public address as a way to communicate outside the network. This address is used to access the internet. The public address available on our computer provides the remote access to our computer. With the help of a public address, we can set up the home server to access the internet. This address is generally assigned by the ISP (Internet Service Provider).

 

Private address:

 

A private address is also known as an internal address, as it is grouped under the LAN addresses. It is used to communicate within the network. These addresses are not routed on the internet so that no traffic can come from the internet to this private address. The address space for the private address is allocated using InterNIC to create our own network. The private addresses are assigned to mainly those computers, printers, smartphones, which are kept inside the home or the computers that are kept within the organization. For example, a private address is assigned to the printer, which is kept inside our home, so that our family member can take out the print from the printer.

 

 

 

 

 

 

TCP/IP MODEL:

 

 

The OSI Model we just looked at is just a reference/logical model. It was designed to describe the functions of the communication system by dividing the communication procedure into smaller and simpler components. TCP/IP was designed and developed by the Department of Defense (DoD) in the 1960s and is based on standard protocols.

 It stands for Transmission Control Protocol/Internet Protocol. The TCP/IP model is a concise version of the OSI model. It contains four layers, unlike the seven layers in the OSI model.

 

The number of layers is sometimes referred to as five or four. Here In this article, we’ll study five layers. The Physical Layer and Data Link Layer are referred to as one single layer as the ‘Physical Layer’ or ‘Network Interface Layer’ in the 4-layer reference.

 

What is the Difference between TCP and IP?

TCP and IP are different protocols of Computer Networks. The basic difference between TCP (Transmission Control Protocol) and IP (Internet Protocol) is in the transmission of data. In simple words, IP finds the destination of the mail and TCP has the work to send and receive the mail. UDP is another protocol, which does not require IP to communicate with another computer. IP is required by only TCP. This is the basic difference between TCP and IP.

 

Layer functionalities

Layers of TCP/IP Model:

§  Application Layer

§  Transport Layer(TCP/UDP)

§  Network/Internet Layer(IP)

§  Data Link Layer (MAC)

§  Physical Layer

 

The diagrammatic comparison of the TCP/IP and OSI model is as follows:

 

 

 

 

 

 

 

1.   Physical Layer

It is a group of applications requiring network communications. This layer is responsible for generating the data and requesting connections. It acts on behalf of the sender and the Network Access layer on the behalf of the receiver. During this article, we will be talking on the behalf of the receiver.

 

2. Data Link Layer

The packet’s network protocol type, in this case, TCP/IP, is identified by the data-link layer. Error prevention and “framing” are also provided by the data-link layer. Point-to-Point Protocol (PPP) framing and Ethernet IEEE 802.2 framing are two examples of data-link layer protocols.

 

3. Internet Layer

This layer parallels the functions of OSI’s Network layer. It defines the protocols which are responsible for the logical transmission of data over the entire network. The main protocols residing at this layer are as follows:

 

IP: IP stands for Internet Protocol and it is responsible for delivering packets from the source host to the destination host by looking at the IP addresses in the packet headers. IP has 2 versions: IPv4 and IPv6. IPv4 is the one that most websites are using currently. But IPv6 is growing as the number of IPv4 addresses is limited in number when compared to the number of users.

ICMP: ICMP stands for Internet Control Message Protocol. It is encapsulated within IP datagrams and is responsible for providing hosts with information about network problems.

ARP: ARP stands for Address Resolution Protocol. Its job is to find the hardware address of a host from a known IP address. ARP has several types: Reverse ARP, Proxy ARP, Gratuitous ARP, and Inverse ARP.

 

4. Transport Layer

The TCP/IP transport layer protocols exchange data receipt acknowledgments and retransmit missing packets to ensure that packets arrive in order and without error. End-to-end communication is referred to as such. Transmission Control Protocol (TCP) and User Datagram Protocol are transport layer protocols at this level (UDP).

 

TCP: Applications can interact with one another using TCP as though they were physically connected by a circuit. TCP transmits data in a way that resembles character-by-character transmission rather than separate packets. A starting point that establishes the connection, the whole transmission in byte order, and an ending point that closes the connection make up this transmission.

UDP: The datagram delivery service is provided by UDP, the other transport layer protocol. Connections between receiving and sending hosts are not verified by UDP.

 

 

5. Application Layer

This layer is analogous to the transport layer of the OSI model. It is responsible for end-to-end communication and error-free delivery of data. It shields the upper-layer applications from the complexities of data. The three main protocols present in this layer are:

 

HTTP and HTTPS: HTTP stands for Hypertext transfer protocol. It is used by the World Wide Web to manage communications between web browsers and servers. HTTPS stands for HTTP-Secure. It is a combination of HTTP with SSL(Secure Socket Layer). It is efficient in cases where the browser needs to fill out forms, sign in, authenticate, and carry out bank transactions.

SSH: SSH stands for Secure Shell. It is a terminal emulations software similar to Telnet. The reason SSH is preferred is because of its ability to maintain the encrypted connection. It sets up a secure session over a TCP/IP connection.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

	TCP
iDefinition	TCP provides the service of exchanging data between applications	IP handles addressing and routing messages to the computers across one or more networks
Connection	Connection Oriented	Connection less method
location	Transport	Internet
Reliability	Reliable	Unreliable
Transfer	Segments to internet layer	Datagrams to physical level
Flow control	Yes	No
Format	TCP segments have a 20 byte header with >= 0 bytes of data	IP datagrams contain a message, or one fragment of a message, that may be up to 65,535 bytes (octets) in length