Not necessarily a wired interface, the livewire is a dedicated dataport. It facilitates communication between any augmentations that can operate commutatively, and enables an augment to read or write wirelessly from an internal secure datadrive to any computer terminal they have access to, including a cranial computer should they possess one.
The livewire is an incredibly useful and flexible computing tool, though it is best used with additional support as described above.
The livewire is a crucial part of the "hackmentation" crowd, where many augmentations can be tweaked beyond their normal operations. Its presence is required to bridge effects across augmentations, though its presence alone is often not all one needs - typically, some skill in electrical or mechanical engineering is also required.