The present invention enables putting much more optic fibers per cable, such as for example even 1,000 or 10,000 times more than the prior art, with an increase in cost that is orders of magnitude smaller. One of the most important variations is using multi-fiber flexible flat jackets that can move freely within the cable's pipe, preferably only in one direction. Preferably at certain intervals (for example every few dozen centimeters or more or 1 or 2 meters or more) the flat jackets are preferably stitched together to each other and/or for example glued and/or otherwise coupled to each other in a way that preferably does not apply pressure to the optic fibers, and preferably are also coupled, preferably at the stitch position, also to the cable, in order to prevent undesired sliding movement of the jackets against each other and/or against the pipe and/or rotating out of orientation.