ISDN stands for Integrated Services Digital Network. It utilizes the traditional twist-copper telephone line, but provides fully digital communication facilities to the customer premise, and allows digital high speed transmission of voice, video and data over the same digital link.
Fully digital ISDN network offers dramatic increase in the transmission speeds, and therefore empowers a whole new breed of applications: video-conferencing, LAN to LAN connection, remote surveillance system, leased line back-up, and digital office phone, etc.
1. Basic Rate Interface (BRI): Transmission speed in BRI is up to 128Kbps (including 2 x 64Kbps channels).
2. Primary Rate Interface (PRI): Transmission speed in PRI is up to 2Mbps (including 30 x 64Kbps channels).