The tmnxPortMode variable indicates if the interface on this port is configured as a service access port or a network access port. If the port mode equals 'access', and the tmnxMDAAssignedType is of ATM MDA family, then tmnxPortEncapType is automatically set to 'atmEncap'. If port mode equals 'access', tmnxPortEncapType must also be configured to 'qEncap' (For Ethernet MDAs) or to 'bcpNullEncap' for Sonet/SDH MDAs. Once the port's operation mode has been configured for 'access' mode, multiple services may be configured on the port. If the port mode equals 'network', tmnxPortEncapType must also be configured to 'nullEncap' (Ethernet MDAs), or 'pppAutoEncap' (Sonet/SDH MDAs) and tmnxPortEncapType is defaulted to those values on the mode change.