In fiber optics transmission, signal attenuation due to external forces or factors, including imperfect joining of optical fibers through splices or connectors. Bending loss also is a form of extrinsic loss as macrobends are caused by excessive bending of the fiber as a result of its physical manipulation and microbends can be caused by excessively tight crimping. See also attenuation, bending loss, connector, intrinsic loss, microbend, macrobend, optical fiber, signal, and splice.