H Channel is a designation for groups of channels on Basic Rate Interface ISDN (BRI-ISDN) services.
What is H Channel
H Channel is a designation for groups of channels on Basic Rate Interface ISDN (BRI-ISDN) services. Standards are defined by the International Telecommunication Union (ITU) and are composed of different combinations of Integrated Services Digital Network (ISDN) B channels.
An H channel is formed of multiple bearer B channels bonded together in a primary rate access (PRA) or primary rate interface (PRI) frame in support of applications with bandwidth requirements that exceed the B channel rate of 64 kbit/s. The channels, once bonded, remain so end-to-end, from transmitter to receiver, through the ISDN network.

The most common configurations are as follows:
- H0 channel, which consists of six B channels multiplexed to provide a data transmission speed of 384 Kbps. This service is sometimes called switched 384 or ISDN H0.
- H11 channel, which consists of 23 B channels to provide 1472 Kbps of bandwidth.
- H11 channel, which consists of 24 B channels to provide 1536 Kbps of bandwidth. This is sometimes called ISDN H11 or switched 1536.
- H12 channel, which consists of 30 B channels to provide 1920 Kbps of bandwidth. This is sometimes called ISDN H12 or switched 1920.