TechRecepies

Early in 1960’s, there were standalone mainframe computers with unintelligent terminals attached. It was an age of centralized processing, where terminals could only avail the services that its mainframe was providing. Every mainframe vendors used to provide different kind of services and there were no standards. It led to Island of Automation, where one mainframe (of say Vendor 1) couldn’t exchange services with other mainframe (of Vendor 2). Department of Defense being a major customer thought of having a kind of standard and thus commenced ARPA (Advanced Research Project Agency) network called ARPAnet. The first protocol developed in 1969, called NCP (Network Connection Protocol), which was however capable of doing only simple file exchange. Therefore, TCP/IP research began at Stanford in 1969 funded by Department of Defense. It was published in a public domain RFC that led to its popularity. At this point the concept of Internetworking was born.

In 1970, ISO (International Organization of Standardization) started it’s work on OSI (Open System Interconnection) 7 layer model, which came into picture not before 1984. Hence there was only D2D 4 layer model till that time.
Also, in 1970, DIX (Digital, Intel and Xerox) together developed a standard called Ethernet II, which was used by ARPAnet, hence also called ARPA Ethernet.

1980s, was the time when transition from Centralized processing to Distributed processing took place. Terminals became intelligent with there own processing components and traditional hosts then evolved as file servers. For eg. Novell Netware, which was very popular at that time. It was the time when actual LAN and WAN definition came into picture.

Also, in 1980s, IEEE took 802 project.
802.1 was the original standard whose responsibility was High-level internetworking protocols and management.
802.2 is the standard for LLC (Logical Link Control), which was created to do Upper layer 7-3 abstraction from Layer 2 Data link. This abstraction was necessary otherwise we wouldn’t be able to use multiple NIC (Network Interface Card) in a machine and bind multiple protocols to a single NIC.
802.3 is the standard for Ethernet
802.4 is the standard for Token bus (Burroughs, Honeywell etc.)
802.5 is the standard for Token ring (IBM)
802.6 is the standard for MAN (Metropolitan Area Networks)
802.7 is the standard for Broadband LAN using Coaxial Cable
802.8 is the standard for Fiber Optic.
802.9 is the standard for Integrated Services LAN (ISDN)
802.10 is the standard for Interoperable LAN Security
802.11 is the standard for Wi-Fi

Today there are different kind of Networks, namely:-

PAN - Personal Area Network is a computer network used for communication among computer devices close to one person

LAN - Local Area Network is a computer network covering a small physical area, like a home, office, or small group of buildings, such as a school, or an airport.

CAN - Campus Area Network is a computer network made up of an interconnection of local area networks (LANs) within a limited geographical area. It can be considered one form of a metropolitan area network, specific to an academic setting.

MAN - Metropolitan Area Network is a network that connects two or more local area networks or campus area networks together but does not extend beyond the boundaries of the immediate town/city.

WAN - Wide Area Network is a computer network that covers a broad area (i.e. any network whose communications links cross metropolitan, regional, or national boundaries.

GAN - Global Area Networks specification is in development by several groups, and there is no common definition. In general, however, a GAN is a model for supporting mobile communications across an arbitrary number of wireless LANs, satellite coverage areas, etc.

SAN - Storage Are Network is a network designed to attach computer storage devices. It is an architecture to attach remote computer storage devices (such as disk arrays, tape libraries, and optical jukeboxes) to servers in such a way that the devices appear as locally attached to the operating system.

CDN - Content Delivery Network, a system of computers on the Internet that deliver content transparently to end users. It facilitates copying pages of a web site to different geographical areas so that they can be accessed quickly by the closest server.

Internetworking - It involves connecting two or more distinct computer networks or network segments via a common routing technology. It has three variants:-

Extranet – It’s for partner or affiliate companies to access organization’s private LAN, though not has full access.

Intranet – It is the internal network of an organization, using the Internet Protocol and IP-based tools such as web browsers and file transfer applications, that is under the control of a single administrative entity.

Internet - It consists of a worldwide interconnection of governmental, academic, public, and private networks based upon the networking technologies of the Internet Protocol Suite. It is the successor of the Advanced Research Projects Agency Network (ARPANET). The Internet is also the communications backbone underlying the World Wide Web (WWW).