Telephone NetworkFigure 8-17

WCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998

Figure 8-18

WCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998

Figure 8-19

WCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998

Analog Switched ServiceFigure 8-20

WCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998

Analog Leased ServiceFigure 8-21

WCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998

Analog HierarchyFigure 8-22

WCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998

Figure 8-23

WCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998

Switched/56 ServiceFigure 8-24

WCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998

DDSFigure 8-25

WCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998

DS HierarchyFigure 8-26

WCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998

T-1 LineFigure 8-27

WCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998

T-1 FrameFigure 8-28

WCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998

Fractional T-1 LineFigure 8-29

WCB/McGraw-Hill The McGraw-Hill Companies, Inc., 1998