In an exemplary embodiment, portable data devices can be coupled with a local area network at any of a multiplicity of points and integrated into the system on a dynamic basis. The preferred system is highly flexible and closely adaptable to changing needs of an individual user. For example, unitary multiple docking devices each receiving a plurality of handheld computerized data terminals may be chained in a series to a single primary controller which may have a further LAN channel including an auxiliary unit which may supply charging power to a further series of multiple docking devices, added to the system as needed. A preferred auxiliary unit is capable of handling two-way communication without the provision of a direction control line in the channel. A preferred LAN system may have unitary printed circuit boards or other rigid network pathways provided with multiple docking receptacles. The control for the LAN system will automatically establish identities for randomly added devices.