Friday, January 27, 2017

The Briefest History of Networking

Desire to communicate

Figure 1. Computers Communicate

There was an early desire to have computers communicate with each other.

This takes the form of binary communication, a transfer of 1’s and 0’s that means something to the computer.

Networking is useful when data in one computer is useful to an application running on another computer.

Early Systems


Start – Stop types of communications predate computing (teletype, etc)

These were relatively low bandwidth, but could carry signals over long distances 

They evolved into modern serial communication for computing where pre-determined synchronization and encoding were used


Modems were developed to significantly reduce the cost of wiring by using the telephone company wires except for the "last mile"

Modems convert the 1’s and 0’s of computer communication into a signal that could travel over telephone lines reliably

Telephone System

There’s a problem though, as Van Jacobson put so well, the Phone System wasn’t about the phones, it was about connecting wires to wires

The utility of the system was dependent on wires running anywhere there was a phone
The wiring of the phone system was the dominant cost

The Phone System revenue was derived by constructing paths between calling endpoints

From manual to Electromechanical Switches

telephone switchboard
Figure 2. Early switchboard phone system

Early phone systems were based on switch-boards, where operators would physically connect one line (wire pair) to another at junctions in the telephone system.

Electromechanical switch
Figure 3. Electromechanical Switch

This evolved into electromechanical switches that utilized the phone number as a program to connect wires within the telephone system such that “operators” were no longer required for the majority of calls.

Problems with the Phone System

The switches had to be centralized with the wiring to be economically feasible, thus creating multiple single points of failure (as well as the development of a monopoly on access to the wiring)

The reliability of any system decreases as the system scale increases and the telephone switches became incredibly large

From the perspective of a computer, until the path is established, data can’t flow, therefore efficiency decreases during any of the telephone systems’ connecting procedures


Abstraction of the Path

Paul Baran, in 1964 theorized a distributed (de-centralized) communications network that could eliminate the points of failure in traditional communications systems

Donald Davies, independently worked on networking and coined the term “packet switching” where the computer split the communications into small segments and, independent of the path, reassembled them at the endpoint

Both are credited with the development of modern distributed computer networking

(We can also aruge that many of the technologies that evolved in parallel in the following years are abstractions of previous networking technologies.)


In 1969, the Advanced Research Projects Agency Network was born, funded by the United States Department of Defense

ARPAnet was an early packet switching network and a precursor to the Internet

It evolved over time and was expanded significantly by the National Science Foundation to support supercomputing at universities in the US

In 1982, the TCP/IP communications protocol was introduced to standardize the protocol for ARPAnet

The result of this, along with the development of the World Wide Web hypertext markup language, provided the means to industrialize the technology that became the Internet

Figure 4. ARPAnet 1969 to 1984

TCP/IP Won -- every time!

In 1974 Bob Kahn and Vint Cerf published “A Protocol for Packet Network Intercommunications” known as Transmission Control Protocol

This provided a means to standardize and industrialize the communications between computers on a network

The addressing structure provided a means to globally connect independently run networks together

World Wide Web

In 1990 Tim Berners-Lee proposed a hypertext project in a client/server configuration called World Wide Web

Using Universal Resource Locators (URLs), enabled human readable identification of materials with a hypertext browser, tying together TCP and the Domain Name System (DNS)

Considered the #1 moment that shaped the world by the British Council (and who can argue with that)


Request for Comments (RFC) play a vital role in the continuing development of networking technologies.

Technologies developed in accordance with the OSI model have provided the means for continued evolution of the foundation technologies into networking as we know it today.


Internet July 11 2015
Figure 5. Internet on July 11, 2015

An industrialized communications network

Capable of communications around problem areas

Global any-to-any addressing, any computer can talk to any computer

Connects independent networks with standardized protocols

Evolves along with multiple network technologies since inception - Thanks TCP/IP!

Operates on electrical, optical and radio frequency interconnecting mechanisms under Creative Commons from LyonLabs

Update:  Great preso on network interfaces: 

1 comment:

  1. Mike i appreciate you sharing this announcement by network vendors on your blog. Feel free to share any more updates on the same in case we are bound to hae developements on the network vendors.