An Explanation and History of Packet Data

Introduction
A packet holds things in real life; we can hold a bunch of objects, same time, by keeping all of them in a packet, which is made of either plastic or paper. In the same way, the term packet data or packets (a most popular term in networks terminology) in telecommunication category also holds a bunch of data bytes. These packets, which hold these bytes, travel from place to place while sending or receiving information.

Technically speaking, a packet is a chunk of data or unit of data sent across a network (Cable or Wireless). Packet-data runs on the packet-switched network, which is considered as superior and reliable when compared to the traditional circuit-switched network. You need to dial-in to send or receive information using circuit-switched networks, while packet switching eliminates dial-in. Packet switching uses radio spectrum when it is actually sending information, rather than keeping an open channel at all times (as is done in circuit switching).

Packet Data Concept
The concept of packets is something like this: the whole message has to be chunked into different packets of similar size and will be sent to the destination across network. All the packets are given a separate number and the destination address. These packets use different available routes and finally, reach the destiny, merge themselves again exactly in the same way to form the original message.

The History of Packet Data
· Actually in 1962-68, packet switching networks developed. This development laid a strong foundation for Internet, which relies on packets to transfer data. In 1969, Internet took birth and ARPANET was the first project, which publicly displayed this development.
· In 1970’s, the first packet network, AlohaNet, was developed at the University of Hawaii.
· ARPANET connected globally in 1973. The same year, Ethernet concept (defines how networks can be connected) outlined, Internet ideas started, Gateway architecture (defines how large networks can be connected together) sketched, and File Transfer Protocol (defines how computers send receive data) specified.
· The year 1974 brought a revolution in the secured data transfer process. This year, TCP (Transmission Control Program) specified; packet data communication is the basis for this TCP, which has been in wide-use throughout the world today! Same year, Telnet, a commercial version of ARPANET also started; this is the first public packet data service. Telnet is mainly used in inter-machine data transfer.
· In 1976, Nortel, a telecommunications MNC, introduced a X.25 data switch, representing the first standards-based commercial application of packet switching.
· Finally, in 1982, the TCP/IP (Transmission Control Protocol/ Internet Protocol) is declared as the protocol suite for ARPANET.

Packets Journey through Network
Packets have become common mode of data carriers through packet switched networks these days! You use packets everywhere without knowing while you make a call, send an email, download a web page, etc.

Let us take an example of an email and see how packets help to carry your email data from one point to another. After you click the Send button of your email editor, the network, that is supposed to facilitate your mail to the destination, breaks your email message into parts of a defined size in bytes. These parts are nothing but what we call packets.

Each packet carries definite information of the following details so that it can reach its destination properly:
· sender's IP address,
· receiver's IP address,
· protocol
· packet number
· data
· data to show at the end of packet
· error correction

Once the packet has the preceding information with it, the network sends the packet toward its destination. The packet takes a certain route out of the available number of routes and travels on its own toward the destination irrespective of whether other packets are following the same route or not. That means, every packet reaches its destination on its own by taking a different route. Actually, this kind of traveling taking different routes toward the same destination helps the network to balance the load. The advantage is that even if one route encounters a problem with an equipment, the packets can be routed to alternative route very easily; this kind of mechanism also ensures the delivery of the entire message.

Different Types of Packet Data
Packet Data Service can be of two types.
1. Type 1 Packet Data Service provides packet data connections based on Internet and ISO (International Standardization Organization) standard protocol stacks
2. Type 2 Packet Data Service provides packet data connections based on CDPD (Cellular Digital Packet Data) protocol stacks.

Advantages of Packet Data
1. Provides utmost security in transferring information
2. Since data is split into tiny packets that may take different routes to a destination, it is hard to eavesdrop on messages
3. Since more than one route available, if one route goes down another may be followed; due to this kind of data transferring strategy, packet-switched networks can withstand large scale destruction


Summary
In summary, packets are efficient way of information transferring units in terms of both security and speed. The results are there for all to see. For example: 3G, the next generation wireless technology, which will provide users with high-speed data transmissions (up to 2Mbps) and the ability to roam globally, uses packet switching.