The present document specifies the functions for the emulation of a basic access over ATM, thus providing an efficient way to connect existing N-ISDN terminal equipment to a PINX over a digital ATM section. Such an ATM connection can be either a (semi-)permanent connection, but might also be a switched virtual connection as defined in related ATM Forum specifications.
The objective of the present document therefore is to specify a mapping scheme for the three types of basic access
information (two B channels: the B1 and B2 channels, the D channel as well as maintenance/control/status information)
into ATM cells. Part of the maintenance/control/status information has to be terminated by an IWU and has to be
substituted by other information applicable at the ATM connection. A reference configuration lays down that the point
of emulation has to be placed at the network side of an extension line.
The present document specifies the static mapping of basic access information to ATM cells.
The present document complements the work of the ATM Forum on circuit emulation services for higher bandwidth.
The present document applies for private networks, however, it is also suitable for public networks.