Used to connect PABXs to the telephone network.

ISDN is the technology that has traditionally been used to connect PABXs

and other phone systems to the telephone network.


It has been the access technology of choice for many years. However, advancements in technology, emergence of Session Initiation Protocol (SIP) and rollout of fibre means we are able to connect like never before.


To take advantage of these new technologies, Spark is updating ISDN to SIP trunking, which provides a more cost-efficient and higher-performing voice access connection than traditional ISDN access.


As a result, Spark no longer provides ISDN services for new installations.


If you need to provide voice access for new installations, please visit our SIP Trunking page