/ http://www.slideshare.net/images/logo.gif / 際際滷Share feed for 際際滷shows by User: cdisp https://public.slidesharecdn.com/v2/images/profile-picture.png Juniper Certified , Focusing on Network Infrastructure, Structural Cabling, System Integrator. Bring solutions you'll never Expected.... --The spreading of a pulse in an optical fiber caused by differences in wave velocity in the medium--