Analogue and Digital Lines
An analogue line is a single copper cable that is run to your building. The installation of these lines is very flexible and cost-effective for small sites, with short lead times for delivery. These lines are normally used for a single voice channel for an analogue device, such as a phone, fax or PDQ machine. Now, analogue lines are used less for voice channels, and are now mainly used to provide broadband services, ADSL, ADSL2+ and FTTC.
Digital lines cover two services, ISDN2e and ISDN30e. They were introduced to address the voice clarity issues and large site installations, compared to analogue lines. Being digital, multiple numbers can be attached to the same line, allowing you to route different numbers to different departments and people.
ISDN2e has a minimum installation of 2 channels, which run over 1 line. A channel refers to the number of concurrent calls you can have at one time. There isn’t a maximum number of installations for ISDN2e, but typically it does not exceed 8 channels.
If you require more than 8 channels, the standard was to use ISDN30e. This service is scalable up to a total of 30 channels, making it more flexible than ISDN2e for larger companies.