Note: A CSU provides local loop equalization[?], transient protection, isolation, and central office loop-back testing capability.
Source: from Federal Standard 1037C
... March-April - [[1] (http://www.michigansocialist.net/mcreynolds/texts/about/1999_03-04_nva.html) | "David McReynolds: Socialist Peacemaker"]] - Article by Paul Buhle: ...