Initial work on a data-only network started in 1972 and was announced by Bell Canada in 1974 as Dataroute.
Bell Canada had long offered leased lines to large business customers like banks and insurance companies who needed to move data between their offices.
In the early 1970s, Bell began exploring ways to make this service more attractive to smaller companies and offices.
In contrast to earlier leased lines, Dataroute allowed multiple customers to share a single channel, folded together using time division multiplexing, and then sent across the country on the existing high-speed microwave links.
In systems where the total utilization is low or peaky, this can allow many customers to use a single link.
Bell's network was already well developed by this point and changes had to be made in order to conform to the initial standard, known as SNAP.
[6] Having already set up many of the underlying systems needed to support X.25, DATAPAC was able to open shortly after the publication of the SNAP standard.