Patent ID: 6647021
Filing Date: 2003-11-11
Classification: H04L

Abstract:
A method of formatting a subscriber bus interface (SBI) frame comprising a plurality of SBI time slots for data communication, the method comprising the steps of:assigning asynchronous transfer mode (ATM) payload bytes to some of the SBI time slots within the SBI frame; assigning narrowband digital signal bytes to some of the SBI time slots within the SBI frame, wherein the SBI frame is configured for transmission from a line card to a control unit, the line card being selected from a group consisting of narrowband and broadband line cards, and wherein the narrowband line cards are selected from a group consisting of DSI, T1 and plain old telephone service (POTS) line cards, and wherein the broadband line card comprises an asymmetrical digital subscriber line (ADSL) line card; and assigning an overhead byte to one of the SBI time slots within the SBI frame, wherein the overhead byte includes back pressure indicator (BPI) bits, each of the BPI bits signifying whether to enable or to disable downstream transmission within a respective one of the channels from the control unit to a respective one of the ports on the ADSL line card.