TIA's Glossary of Telecommunication Terms

0-9 | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

Search Term

office classification

Prior to divestiture, numbers that were assigned to offices according to their hierarchical function in the U.S. public switched telephone network. Note 1: The following class numbers are used:

• Class 1: Regional Center (RC)
• Class 2: Sectional Center (SC)
• Class 3: Primary Center (PC)
• Class 4: Toll Center (TC) [Only if operators are present; otherwise Toll Point (TP)]
• Class 5: End Office (EO) [Local central office]

Note 2: Any one center handles traffic from one center to two or more centers lower in the hierarchy. Since divestiture, these designations have become less firm.

Back