What is an integrated digital network of services?
Integrated digital network (ISDN) is a network that uses existing copper cabling to carry digital signals. ISDNS can transmit voice operation and data packets. These networks are based on the dual channel architecture with the "B" channel or the bearer and the channel "D" or Delta.
The "B" channel is used for voice, data, multimedia and video calls and works on 64 kbps. The "B" channels can be connected together for applications that require a higher bandwidth. The "D" channel, which can be 16 or 64 kbps, is usually used by switching the device to allow communication between the Integrated Services digital network and the user's website. These channels are available on different interfaces.
The Basic Rate (BRI) interface is the most common interface that people use to connect to the Internet. ISDN BRI has two "B" channels and a single channel 16 kbps "D" running through one copper telephone line and earns the name "2b+D". BRI can support two votes, fax or data converters and packets switched by convData erzation simultaneously. Multiple Bris can be combined for further bandwidth depending on the use of the integrated digital network hardware.
The second option is known as the primary rate interface (PRI). They usually use corporations or businesses that require intense bandwidth. The Integrated Services Digital Network Pri supports up to 23 B "channels and a single channel 64 kbps" D ". These configurations are known as "23b+D". In Europe it supports 30 "B" channels and is known as "30b+D".
The correct configuration of integrated digital network services requires defining how the ISDN line will be used. Customer needs or telephone companies may require each channel "B" to have a separate phone number. Customers will also have to know their service profile identifier (SPID). SPIDs look like a phone number additional digits and are used to identify ISDN to Telefo networknative companies. Like telephone numbers, each channel can be assigned its own SPID.
The digital network of integrated services requires additional hardware and has some practical restrictions. Hardware requirements include the ISDN adapter and router. Customers must be physically located not more than 18,000 feet (5,486.4 m) or approximately 3.4 miles (5.471 km) from the central telephone office to obtain the ISDN service. Dear hardware "repeater" can sometimes, but not always, to prevent distance limitation.
Although ISDN has existed for decades, only in the 90s of the regional bell operating company (RBOC) in the United States agreed on the National Standard ISDN, Ni-1. With this standard, customers could buy ISDN equipment from each manufacturer and be sure to be compatible with the center of its specific Central Office Switch provider. In recent years, the use of ISDNS has decreased due to sharp popularity of more cost -effective broadband servicesand cable modems. ISDN is still used in more distant areas where broadband services are not yet available and as a reserved backup lines.