Digital data is used today for the modern transfer of information. A transmitting device such as a computer, smartphone, activity tracker, or modem breaks Digital Data down into packets. The receiving device reassembles these packets upon reaching the destination in the alternate device it is being sent to. Breaking data down into packets ensures smoother and faster transmission with less latency, but why do we break data into packets?
We break Digital Data into packets to increase data transfer efficiency and enable multiple pathways to one destination. The transmission of data packets travels across networks, taking the shortest path possible. All the packets are reassembled at the receiving end in the correct order.
This article will shed light on why it’s vital to break data into packets. We will also explain what a data packet is and highlight its components, emphasizing each part’s role.
What Is a Digital Data?
Data are types of information collected, measured, reported, investigated, analyzed, and transmitted for this explanation. Data is represented in either analog or digital form.
Digital Data is data information that utilizes different forms and takes that information and converts it into a format that can either be stored or transmitted. Information technology uses machine language digital data forms by using binary code and two numbers; 0 and 1.
This digital data can be interpreted by various technologies such as computers or wifi networks. DNA genetic code is a naturally occurring form of digital data storage.
“The volume of data stored in the Global StorageSphere is doubling approximately every four years,” said John Rydning, research vice president, IDC’s Global DataSphere.
What Is a Data Packet?
A Data Packet is not the information itself. A data packet contains or encloses the information that is being sent to another computer or device. A data packet is a basic unit of communication, a small section of a more significant piece of data transmitted over a network. Each packet is tiny, about 64 kilobytes for IP (Internet Protocol) packet payloads and 1.5 kilobytes for ethernet packets depending on the protocol used for data transmission.
A data packet is inclusive of the source, the destination, and the payload. Upon reaching the intended destination, individual packets go through a process that assembles them into one “block” of data.
Each Packet Is Three Different Parts:
- One is the header, and the other is the payload which is the actual data or information that needs transmitting.
- Each packet also has a trailer or footer,
- Packets from numerous different computers or sources can travel along the same paths in any order. The payload contains all the information about the packet.
Header and Payload
The header is a tag or marker, link layer, or portion of a data packet that identifies the source of the packet and the intended destination. The inclusion of the header is only necessary during the transmission process, and as a result, the header is removed or stripped from the packet when it reaches the intended destination.
The payload, which is the actual data or information that needs to be transmitted, is the only one received at the destination. The header contains the sender and receiver’s IP addresses and the exact number of packets of data created during packet switching.
The trailer or footer contains a few electronic bits that tell the receiving computer or device when it has reached the end of the packet sequence. Depending on the complexity of the receiving device, it will also do verification of the packet, and if the verification doesn’t work properly, it may ask your computer to retransmit the packet.
All this information makes it possible to reassemble these packets once they reach their destination.
Packet Switching: Why Break Data Into Packets?
Packet switching is used on the Internet and most local area networks. Packet Switching transmits data across digital networks by breaking it down into blocks or packets. Packet switching and splitting data into packets before transmission is more or less the same thing.
Breaking data into packets optimizes the use of the channel capacity available in digital networks and minimizes the time it takes for data to pass across the network.
There Are Two Major Types Of Packet Switching:
- Connectionless Packet Switching. This type of packet switching includes multiple packets, each individually routed.
- Connection-Oriented Packet Switching. In this packet switching, data packets are first assembled and then numbered. They then travel across a predefined route in a specific order.
Data Packet Size
Packets have varying sizes depending on the speed of the network and the overall size of the file. Smaller packet sizes result in slower effective data rates, while larger packets are effectively faster. Choosing tiny packet sizes can negatively impact performance, and it makes more sense to use a larger packet size for bigger files. Using smaller sizes can take up too much time and cause a lag.
A TCP connection, for instance, can determine which packet size will be used during transmission by requesting both the sender and the receiver to send the maximum packet size they can transmit. In this case, the smaller size is the wiser choice.
Requesting information on capacity makes it possible to vary the sizes of packets sent, and the networks that can handle bigger packet sizes are free to do so. If there’s inadequate information on the suitable dimensions for the whole path, using a fixed size is advisable. This size can be 576 bytes, which is considered safe for use.
Data Packet Tag
Each data packet has a tag or identification number, which helps when the receiver reassembles the data at the destination. In most cases, the process of reassembling the packets may include an Automatic-repeat request which can pinpoint any missing segments.
If any packet is lost or transmission fails, the Automatic-repeat request is responsible for requesting retransmission from the source.
Splitting Data
Splitting data enhances performance and prevents congestion and slow data transmission. Packet switching may be necessary in cases where there is an unstable network connection.
It’s also required when the overall file is larger than the maximum transmission unit of the network sending the data. In cases where there’s an unstable connection, packet switching increases the chances of each packet reaching its destination without mishap.
How Is Data Split Into Packets?
Four separate layers make up a TCP/IP Transfer Control Protocol/ Internet Protocol Stack. These layers are the transport, application, network, and link layers, and together they’re termed “the stack.”
The splitting of data into smaller packets takes place in the transport layer. When a device sends data, the first stop is the application layer, and the last is the link layer.
Upon being received, data moves from the link layer to the network where the destination is specified.
Functions of Each Layer
The Application Layer
The purpose of the application layer is to supply interfaces and protocols that users require. It makes it possible for the user to access the services offered by the network.
The application layer includes attributes present in the other layers, and it’s responsible for handling any errors that may occur and recovering messages. This layer is also responsible for naming network devices, formatting messages and emails, and transferring files.
The application layer employs the use of several protocols, which are:
- File Transfer Protocol (FTP)
- HyperText Transfer Protocol (HTTP)
- Domain Name System (DNS)
- Simple Mail Transfer Protocol (SMTP)
- Simple Network Management Protocol (SNMP)
- Telnet
Transport Layer
The transport layer is the one responsible for splitting the data into packets. It’s also responsible for regulating communication between the source and the destination, which tracks data from one application to another.
The transport layer is the one that establishes the link that is needed to start or end an IP session, and it also regulates and controls transmission errors.
The two most common transport layer protocols are the User Datagram Protocol (UDP) and the Transmission Control Protocol (TCP). The transport layer essentially controls the quality of the overall service.
Network Layer
This layer comes in third place in the OSI model. Its primary function is to regulate anything related to connections between two or more networks.
This layer is responsible for selecting the routes to be used by the data packets. It’s also responsible for addressing and receiving data packets from separate networks.
Link Layer
This layer comes in second in the OSI model. The link-layer provides a link between hardware and software.
As a result, it includes the software required to control the hardware. Data Link layer protocols are suitable for use in both LAN and WAN.
The physical layer (hardware) sends data bits to the link layer, and the link layer formats the bits into groups which are termed data link frames. This layer also has the responsibility of detecting and correcting any errors that may occur in the hardware.
Other layers are the session layer, the data link layer, and the physical layer. The session layer works hand in hand with the transport layer to control and regulate connections between different computers.
The data link layer is in charge of communication between devices that are using the same network. The physical layer is where the data packets are transformed into electrical or optical pulses and then transmitted in small units of information called bits. The mode of transmission can be cables or radio waves.
Final Word
Breaking data into packets increases the efficiency of transmission and reduces latency. It also enables data to travel to the destination simultaneously, using different pathways.
A data packet consists of three parts which are the header, payload, and trailer. The header acts as a tag and has information like the packet source and the destination, and the payload is the actual data that needs transmission. The trailer tells the receiving computer or device when it has reached the end of the packet sequence
Splitting data into packets is advantageous when there is a slow network or when the file that needs to be transmitted exceeds the limits of what the network in use can handle.
References:
- Stanford: Basics Of Internet Data Transmission
- Springer: Packets, Packet Headers, And Header Format
- UiO: Transport Layer Function
- Section: Understanding TCP/IP Transport Layer (Layer 3) Protocols- TCP and UDP
- South Eastern: Networking Protocols
- BJC: Reliable Transmission On Unreliable Networks: TCP