real-time variable bit rate

See rt-VBR. Mountain Bell (Arizona, Colorado, Idaho, Montana, New Mexico, Utah, and Wyoming) Northwestern Bell (Iowa, Minnesota, North Dakota, Nebraska, and South Dakota) Pacific Northwest Bell (Oregon and Washington) Southwestern Bell (Arkansas, Kansas, Missouri, Oklahoma, and Texas) Pacific Bell (California) Nevada Bell (Nevada) New England Telephone (Massachusetts, Maine, New Hampshire, Rhode Island, and Vermont) New York Telephone (New York) Bell Operating Companies (Primary States of Operation), Pre-divestiture