[en] It has been found that for a focused laser beam propagating in vacuum, there exist 'natural' channels for laser driven electron acceleration, which emerge just beyond the beam width and extend along the diffraction angle for a few Rayleigh lengths. These channels have the similar characteristics to that of a wave guide tube of conventional accelerators: a subluminous wave phase velocity in conjunction with a strong longitudinal acceleration electric field. Relativistic electrons injected into these channels can be captured in the acceleration phase of the wave for sufficiently long time and gain considerable net energy from the laser field. The basic conditions for this acceleration scheme to emerge are addressed here