What are the differences between ADSL & ISDN?
The two services are NOT the same. ISDN provides two voice channels or a 128 Kbps data channel while ADSL is predominantly a data pipe providing an asymmetrical bandwidth of up to 8 Mbps downstream and 1 Mbps upstream under good conditions. However, an ADSL access network will be an overlay network and therefore will not require the expensive and time-consuming switch upgrades that held ISDN back for so long. If ADSL service prices resemble ISDN service prices, then one would expect ADSL to be favored for Internet and video application.