Some sections of the John Snow site are labeled as broadband (). Usually modems are either voiceband with transmission across telephone lines typically used for sound, or broadband with transmission across cable lines, high-speed telephone lines or via satellite, featuring much wider communication channels.
Voiceband versus Broadband
With information flowing from the worldwide web to personal computers, a crucial element is the attachment to the internet, sometimes referred to as the pipeline. Like oil or water pipelines, the larger the pipe, the greater the volume flowing per unit time. With the internet, the volume flow is information, stored and transmitted in various formats. Telephone modems which transmit voiceband function very well with small files consisting mainly of text, with no observable delays in information access. Yet with large files consisting of complex graphics or perhaps sound or video, the modem pipelines are too small, and the information takes a long time to be transmitted. Larger pipelines – termed broadband – have been created and are constantly being improved. With such broadband transmission, sound, video and movie files become as transmittable as text files with conventional telephone modems.
Economically Developed Countries
Broadband use in North America is dramatically increasing. The two most popular connections in the United States remain cable modems and high-speed data connections being offered by the telephone industry called digital subscriber lines, or DSL. Americans have adopted broadband internet connections faster than most technological inventions of the past century, taking only six years to gain access to 10 million homes (in contrast, the telephone took 35 years). Yet the USA still lags many other countries and regions (see below).
Economically Less-developed Countries
Voiceband transmission via telephone lines remains the main form of internet linkage in the developing world. The expense of wiring cities with optical fiber or copper wires for broadband transmission will remain high. Yet two other mechanisms for broadband transmission hold great promise, opening the door to rapid expansion in cities and towns. These are high-speed satellite transmission and broadband wireless networks. The latter category is similar but much faster to cellular telephone systems, which are now common in many developing countries.
John Snow Site
Being future oriented but about the past, the John Snow Site caters to high-speed connections, using broadband transmission for sight and sound presentations and for maps with high resolution graphics.