eSCO, or Extended Synchronous Connection Oriented links, refers to the ability of a Bluetooth device to connect to multiple other devices at one time. eSCO is an variation of SCO (Synchronous Connection Oriented links), which transmitted single voice links but without the ability to retransmit files.
Any Bluetooth-enabled device featuring version 1.2 and beyond is enabled with this profile capability, though the enhanced data rate introduced in versions 2.0 and beyond make multiple connections (using Multipoint) smoother and faster. eSCO also furthers Bluetooth technology through improvement of audio files sent device-to-device by introducing the ability to re-send files corrupted during the sending process and an overall increase in monitoring during file transfer.
Because of this improvement, Bluetooth can create increasingly larger, more diverse, and more stable personal area networks (piconets) with each released version.