/>
X

Photos: The tech at the heart of the internet

National Museum of Computing journeys back to the net's first days
40153142-1-p1040814.jpg
1 of 7 Nick Heath/ZDNet

National Museum of Computing journeys back to the net's first days

They were Britain's very own internet pioneers, experimenting with email and VoIP before today's web 2.0 generation were even born.

Donald Davies might not be a household name but without the work carried out by Davies and his colleagues at the National Physical Laboratory (NPL) in the 1960s and 1970s, you wouldn't be browsing this website today.

The NPL researchers developed packet switching, the technology that allows information to be sent and received over the internet.

The role they played is explored in a new exhibition The Technology of the Internet that opened at The National Museum of Computing in Bletchley Park recently.

In 1970 Davies and colleagues built the world's first packet switched computer networks to allow them to send data between about 200 teletype terminals, like the ones seen here, dotted around the square kilometre NPL site at Teddington, Middlesex.

The technology allowed information to be split into parcels and labelled with an address before being sent over a network and stitched back together for another terminal to receive at the other end.

"At its most basic level the router that you use today will use packet switching, which is the same process that was used by the routers at NPL. At the core, the mechanism that's sending information across the web is still packet switching," said Kevin Murrell, trustee at The National Museum of Computing.

Photo strong: Nick Heath/silicon.com

40153142-2-tnmoc2-1-1.jpg
2 of 7 Nick Heath/ZDNet

The teletype terminals used by the NPL would print network status messages for the user as they connected to the network.

<="" center="">

Photo credits: Nick Heath/silicon.com

40153142-3-p1040769.jpg
3 of 7 Nick Heath/ZDNet

Eventually terminals with built-in green screen monitors, known as glass teletypes, were used to connect to the network.

But despite each connection on the NPL network running at an impressive 2Mbps, the process of connecting was a lot more complex than firing up your web browser today.

Users would have a coloured keypad next to the teletype machine, and would have to press different colour buttons to start sending and receiving information, as seen above.

First a user would press the yellow button at the bottom of the keypad to connect to initiate a connection with one of 12 central computer systems where the data or software they needed was stored.

They would then type the name of the system that they wanted to connect to and then press the green button, which would allow information to be sent between the machines. To disconnect the user would then have to push the yellow button at the top of the keypad.

Photos credit: Nick Heath/silicon.com

40153142-4-bletchleypic4.jpg
4 of 7 Nick Heath/ZDNet

An early version of VoIP was tried out on the NPL network.

NPL researchers experimented with encoding people's voices as digital data and sending it across the network, similar to the way that VoIP systems such as Skype work now.

The researchers also experimented with technology that resembled today's web pages, using a system called Scrapbook.

Scrapbook allowed researchers to create links between documents hosted on a central computer, an idea that is a key part of the linked pages on contemporary websites.

They also discovered they could use Scrapbook to send messages to each other, resulting in what The National Museum of Computing's (TNMOC) Murrell calls "a very early form of email".

Above is an animation designed by TNMOC to show how email is sent over the modern internet: an email is sent from the computer in the bottom left of the picture, the email is broken up into packets of data and travels through a web of different internet exchanges to the mail server in the top right. The mail server then determines the correct address to send the email to and sends the data to the computer in the top left of the picture, where the data packets are stitched back together into the email.

Photo credits: The National Museum of Computing

40153142-5-p1040795-1.jpg
5 of 7 Nick Heath/ZDNet

This device is called a multiplexer and was developed at NPL to carry out much of the same functions as the router does today.

It was created to help manage the flow of information packets across NPL's network.

Before packet switching was invented, businesses relied on computer networks where terminals needed their own dedicated telephone line to connect to the central mainframe.

The advantage of a packet switching system over this so-called circuit switching is that it allows a central computer to send information to multiple computers over a single comms link and to route the information through the fastest part of the network.

Photo credit: Nick Heath/silicon.com

40153142-6-p1040773.jpg
6 of 7 Nick Heath/ZDNet

Here you can see information being sent and received over TNMOC's model of the NPL network, in a similar process to the one used to transmit data over the internet today.

The next step towards today's internet after the NPL network came in the 1970s after packet switching technology was adopted by the US military when it created Arpanet - the Advanced Research Projects Agency Network - to connect its bases in the US.

Photo credit: Nick Heath/silicon.com

40153142-7-bletchleypacketswitching.jpg
7 of 7 Nick Heath/ZDNet

The museum has set up this display to demonstrate the long and winding road taken by information as it wings its way across the internet.

The screen shows the journey taken by information on The National Museum of Computing's website as it travels from the site's server to the user's computer.

Here you can see information starting out in London before passing through internet exchanges across England and finishing at an exchange in Leeds.

<="" center="">

Photo credits: Nick Heath/silicon.com

Related Galleries

Say hello to the early days of web browsers
netscape-shutterstock-189041855.jpg

Related Galleries

Say hello to the early days of web browsers

9 Photos
TRENDnet TUC-ET5G USB-C 3.1 to 5GBASE-T Ethernet adapter
TRENDnet TUC-ET5G

Related Galleries

TRENDnet TUC-ET5G USB-C 3.1 to 5GBASE-T Ethernet adapter

20 Photos
Anker PowerExpand 8-in-1 USB-C hub
Anker PowerExpand 8-in-1 USB-C hub

Related Galleries

Anker PowerExpand 8-in-1 USB-C hub

7 Photos
Netgear Orbi RBK752 tri-band Gigabit Wi-Fi 6 mesh
Netgear Orbi RBK752

Related Galleries

Netgear Orbi RBK752 tri-band Gigabit Wi-Fi 6 mesh

8 Photos
Plugable UD-CA1A USB-C dock
Plugable UD-CA1A USB-C docking station

Related Galleries

Plugable UD-CA1A USB-C dock

7 Photos
OWC Thunderbolt 3 10G Ethernet Adapter
OWC Thunderbolt 3 10G Ethernet Adapter

Related Galleries

OWC Thunderbolt 3 10G Ethernet Adapter

4 Photos
Plugable super-fast 2.5Gbps Ethernet adapter (in pictures)
Plugable 2.5Gbps Ethernet adapter

Related Galleries

Plugable super-fast 2.5Gbps Ethernet adapter (in pictures)

14 Photos