Transmission Control Protocol / Internet Protocol (TCP/IP)

TCP/IP:

The TCP/IP model allows the clients to adopt a specific behaviour to link a device with the internet. Moreover, TCP/IP helps how to move data between the devices using the network. When multiple computer networks are linked together, it assists users in building a virtual network. The prime objective of the TCP/IP model is to allow long-distance communication. The TCP/IP Protocol Stack is built primarily to provide an extremely stable and end-to-end byte stream over an insecure internet network.

Through utilizing a protocol named TCP/IP, the internet operates. The internet’s fundamental networking language is TCP/IP. In simple words, TCP/IP helps one machine to communicate over the internet to another computer by assembling data packets and delivering them to the correct place. A packet, often more commonly known as a network packet, is a unit of data sent from one place to the next system for those who do not know.   Like an atom is the tiny unit of a cell, the smallest unit of knowledge distributed over the web is known as a packet.

Transmission Control Protocol (TCP):

As implied in the term, TCP/IP has two layers. It is the top layer’s duty, TCP, to take massive volumes of data, compile it into packets and send them on their way to receive a fellow TCP layer, which transforms the packets into usable data/information.

Internet Protocol (IP):

The lower portion, IP, is the couple’s contextual feature that enables the time frame to be transmitted and retrieved to the right position. In terms of synthesis, if you think about IP, the IP layer acts as a GPS packet to locate the right destination. Each packet passes through a gateway computer (signs on the road), just like a car traveling on a highway, which helps to forward the packets to the correct location.

TCP/IP Characteristics:

The essential features related to TCP/IP are as given below.

• Provision for an adaptable TCP/IP framework
• The addition of more devices to integrate with the network is feasible
• The TCP/IP network will remain active till the source, and destination devices are working appropriately
• A connection-oriented protocol
• It provides reliability as well as security of data arrival if it remains out of sequence by putting its order back
• Permits to apply flow control; therefore, the sender cannot suppress the receiver using data

TCP/IP Layers:

There are abstract layers embedded in the TCP/IP. The TCP/IP protocol’s performance is classified into four layers, where each consists of specified protocols. TCP/IP is a layered system of the server framework where each layer is described by a unique feature to be executed. Both these four levels of TCP/IP function together to relay information from one layer to another. Fig. 1 briefly depicts the framework of the TCP/IP model.

1. Application Layer
2. Transport Layer
3. Internet Layer
4. Network Access Layer

The four abstract layers hidden in the TCP/IP protocol permit efficient data communication among data packets, programs, and networking equipment using the internet. Moreover, it ensures the packets’ delivery on the right spot.

1. Application Layer:

The application layer connects with a program, which is the OSI model’s highest standard. The OSI layer, which is nearest to the end-user, is the device layer; this suggests that the OSI device layer helps users interface with another program. For the communication aspect, the application layer communicates with the program. The application program’s understanding of data is always beyond the reach of the OSI model.

The typical examples from daily life are file transferring and e-mail etc.

The role of the application layer includes.

1. It helps identify the partners for communication, evaluating the availability of resources, and syncing the communication.
2. Allows the clients to logon as a remote host.
3. The layers give several email services.
4. The program gives distributed database sources as well as grant access to worldwide information regarding several objects.

2. Transport Layer:

In order to process smooth communication from a device to the destination, the transport layer is built on the internet layer or network layer. It is hosted utilizing one or more different networks, and the consistency of service functions is often retained.

The layer states the sum of information that should be submitted where and at which point. The transport layer draws on the message that the framework layer gets. It assures the data elements are produced in series and error-free. Moreover, it helps control the consistency of link via error controlling, error controlling, or applying the concept of segmentation/de-segmentation. The transport layer often gives an indication of the effective transfer of the data and sends the next data if the case is error-free. The real example of the transport layer is TCP.

The significant role of the transport layer includes.

1. It makes a sequence of the message received during the session layer. The layer divides the message into chunks of segments and numeric.
2. It ensures the delivery of the message to the right process on approaching the destination device.
3. It also ensures that the whole message is reached to the destination point without any destruction; otherwise, the message will be sent again.

3. Internet Layer:

The second layer of TCP/IP is known as the internet layer or network layer. This layer’s purpose is to send packets from the network to other devices till the packets arrive at the destination. It does follow which track or route the packets take to reach the goal. The network layer provides a functional behaviour to transfer a flexible amount of data from a node to another employing several networks.

The management protocols that have a direct relationship with the network layer are listed below.

• Routing Protocols
• Multicast Group Management
• Network-Layer Address Assignment

Network Interface Layer:

The network interface layer or network access layers is the fourth layer of the TCP/IP model that assists the clients in the form of a definition of how to send the data using a network. The layer has a keen observation over the bits signalling by hardware devices directly related to the network’s medium, including twisted cables, coaxial cables, optical fiber cables, etc.

The network interface layer declares data communication through the physical medium using the internet. Moreover, the network layer is liable to transmit the data between two systems, communicating on the unique network. 

OSI Model Vs TCP/IP Model:

In the below-given Table 1, we have briefly described the significant differences among the OSI and TCP/IP models.

Table 1: OSI Model Vs TCP/IP Model

OSI Model	TCP/IP Model
OSI is the short form of Open System Interconnection	TCP/IP is the short form of Transmission Control Protocol/Internet Protocol
The model is developed and designed by ISO	The model is created and designed by ARPANET
There is a clear difference between services and protocols	There is not any clear distinction between services, interfaces, and protocols
The network layer is utilized for the definition of data routing and protocols	It only uses the internet layer
A vertical approach is adopted	A horizontal approach is adopted
Two different layers (Physical & Data Link) are used for defining the working of bottom layers	Only one layer is used in the case of TCP/IP
The model retains seven layers	The model retains four layers
In the model, the only transport layer is connection-oriented	The layer is both connection-oriented as well as connectionless
In the model, both the data link layer & physical layer are separate as both have different standards	In the model, a single network layer performs the functionality of physical and data link
The model is proposed after the invention of the internet	The model is presented before the invention of the internet
5 bytes minimum header size	20 bytes minimum header size

Fig. 2 wisely depicts the layering distinction among both the OSI reference model and the TCP/IP conceptual model.

TCP/IP Common Protocols:

The commonly used TCP/IP protocols are as given.

1. Transmission Control Protocol (TCP):

The internet protocol is a full package that converts the data into chunks known as segments and then reassembles the chunked data on the receiving end.

2. Internet Protocol (IP):

Internet protocol or IP address is a string of numbers. Each device connected to the internet has a unique address. The IP address aims to perform smooth communication among the devices associated with the internet. Moreover, the internet connection is established on an IP address. The routing function of the IP address permits internetworking. The integrated setup of TCP and IP makes a virtual connection for communication that starts from the source and ends at the destination.

3. Hypertext Transfer Protocol (HTTP):

HTTP is the basics of the World Wide Web (WWW). The world wide web is the most common service on the internet—the networks based on an application known as Hypertext Transfer Protocol (HTTP). Web pages are built by using a specific language known as Hypertext Markup Language (HTML). Over the internet, web browsers and servers converse with each other with the help of HTTP. The protocol is the application level as it is present on the top of the TCP layer. In such a case, web browsers and servers are the applications.

HTTP is used to transfer the resources, mostly web pages, with the webserver clients. Several browsers include Internet Explorer, Safari, Mozilla Firefox, Google Chrome, etc., are used by web clients. Browsers assists to bring web pages that the client requests from remote servers.

4. Simple Mail Transfer Protocol (SMTP):

The internet is used for maintaining connections. One of the most excessively used applications used over the internet is e-mail. The application-level protocol used for e-mail is the Simple Mail Transfer Protocol (SMTP) based on text. However, SMTP is link oriented, unlike HTTP. SMTP is a complex protocol as compared with the HTTP. But the variety of commands is wide in SMTP.

5. Simple Network Management Protocol (SNMP):

SNMP is an architecture used to manage the systems connected with the internet employing TCP/IP protocol. There is no other protocol that can monitor or identify the devices for managing the network except SNMP. The protocol assists in evaluating the current status of the connected devices as well as judges the status of devices connected with the internet in real-time.

6. Domain Name Server (DNS):

Domain name service (DNS) is a distributed database that assists in tracking devices’ names and the integrated internet protocol addresses present on the internet. Multiple devices are connected to the internet host part of the domain name service database and the software which permits the others to access it. Such systems are also called DNS servers. DNS server only holds a subset of the database, not the entire database. Therefore, if a computer requests a domain name not present in the DNS server, it redirects the computer towards a new DNS server. The hierarchy of the DNS is just like the structure of the internet protocol routing hierarchy.

Whenever an internet connection is established, a single primary and one or greater than one secondary DNS server become part of the installation. The best example of the DNS is whenever a client requests to browse a website, the web browser first connects with the primary DNS server from where it will achieve the IP address for the domain name as requested by the client. Then the browser will be associated with the target device to open the web page.

7. Terminal Network (TELNET):

TELNET is used to create a connection between the local computer and the remote devices. It offers connectivity in such a pattern that the client can simulate the local computer with the removed device.

8. File Transfer Protocol (FTP):

File transfer protocol is commonly used as the standard protocol for the communication of data (files) from one device to another.

TCP/IP Advantages:

The benefits of the TCP/IP model are as mentioned below.

1. Helpful in establishing a connection between two computers.
2. It assists in building a connection between various types of devices or computers.
3. The operation is independent of the OS.
4. Valid for several routing protocols.
5. It gives leverage to enterprises and organizations to establish internetwork.
6. It has a tremendous scalable client-server framework.

TCP/IP Disadvantages:

The disadvantages of the TCP/IP model are as mentioned below.

1. The model is a bit complex in accordance with settings and managing.
2. The overhead of the model is more generous than the Internet Packet Exchange (IPX).
3. The transport layer is not responsible for delivering the packets.
4. Replacing the protocol of the model is not as much straightforward.
5. There exists no boundary that defines the services, interfaces, and protocols in the model.

Summary and Facts:

What do you mean by the TCP/IP Model?

• The TCP/IP model allows the clients to adopt a specific behavior to link a device with the internet.
• TCP/IP helps how to move data between the devices using the network.
• In the case of multiple computer networks linked together, it helps users build a virtual network.
• The prime objective of the TCP/IP model is to allow long-distance communication.
• The TCP/IP Protocol Stack is built primarily to provide an extremely stable and end-to-end byte stream over an insecure internet network.
• The internet’s fundamental networking language is TCP/IP.
• TCP/IP helps one machine communicate over the internet to another computer by assembling data packets and delivering them to the correct place.

What TCP stands for and its functionality?

• TCP stands for Transmission Control Protocol.
• TCP takes massive volumes of data, compiles it into packets, and sends them on their way to receive a fellow TCP layer, which transforms the packets into usable data/information.

What IP stands for and its functionality?

• IP stands for Internet Protocol.
• The lower portion, IP, is the couple’s contextual feature that enables the time frame to be transmitted and retrieved to the right position.
• Each packet passes through a gateway computer (signs on the road), just like a car traveling on a highway, which helps to forward the packets to the correct location.

What are the key characteristics of TCP/IP?

• An adaptable TCP/IP framework.
• Allow more devices to add to the network.
• Remain active till the source and destination devices are working appropriately.
• A connection-oriented protocol.
• Provides reliability as well as security of data.
• Permits to apply flow control.

Name and describe the functionality of TCP/IP layers?

1. Application Layer aims to confirm communication among applications on the network.
2. Transport Layer is used for resolving host-to-host communication.
3. Internet Layer is the medium for connection of hosts with other networks.
4. Network Interface Layer is the medium used physically for network connection. The purpose of this physical equipment is to interconnect nodes and servers.

Write down the commonly used protocols of TCP/IP over the internet?

1. Transmission Control Protocol (TCP)
2. Internet Protocol (IP)
3. Hypertext Transfer Protocol (HTTP)
4. Simple Mail Transfer Protocol (SMTP)
5. Simple Network Management Protocol (SNMP)
6. Domain Name Server (DNS)
7. Terminal Network (TELNET)
8. File Transfer Protocol (FTP)

List down the advantages of the TCP/IP conceptual model?

1. Functions like connection medium between computers.
2. The connection can be built for computers or other devices.
3. Independent Operation.
4. Valid for several routing protocols.
5. Works well for the interconnection of organizations.
6. It has a great scalable client-server framework.

List down the disadvantages of the TCP/IP conceptual model?

1. Complicated model.
2. The overhead, higher than IPX.
3. The transport layer is not responsible for delivering the packets.
4. Replacing the protocol of the model is not as much easier.
5. No boundary that defines the services, interfaces, and protocols in the model.

Read more about Protocol Layers

References:

1. https://www.hostingadvice.com/blog/tcpip-make-internet-work/#:~:text=The%20Internet%20works%20by%20using,Transmission%20Control%20Protocol%2FInternet%20Protocol.&text=In%20base%20terms%2C%20TCP%2FIP,sending%20them%20to%20right%20location.
2. https://docs.oracle.com/cd/E19683-01/806-4075/ipov-10/index.html
3. https://www.guru99.com/tcp-ip-model.html#2
4. http://www.technologyuk.net/computing/computer-networks/internet/tcp-ip-stack.shtml
5. https://www.guru99.com/images/1/093019_0615_TCPIPModelW3.png