Data transmission over multiple upstream channels within a cable modem system

Abstract

A system and method are disclosed for transmitting upstream data from a cable modem within a cable television plant. One aspect of the invention pertains to a method that includes transmitting a first portion of the upstream data on a first upstream channel from the cable modem and transmitting a second portion of the upstream data on a second upstream channel from the cable modem. The second upstream channel differs from the first upstream channel. In another aspect, the invention pertains to a cable modem that includes a processor configured to initiate transmission on multiple upstream channels. The cable modem further includes an upstream transmitting component operating in conjunction with the processor and configurable by the processor to transmit data over multiple upstream channels. In one embodiment, the upstream transmitting component includes a first transmitter that is capable of being configured by the processor to transmit data at both a first upstream channel and a second transmitter that is capable of being configured by the processor to transmit at a second upstream channel that differs from the first upstream channel.

Description

CROSS REFERENCE TO RELATED PATENT APPLICATION [0001] This application is a continuation of and claims priority of U.S. patent application Ser. No. 09 / 330,225 (Attorney Docket No. CISCP086), entitled DATA TRANSMISSION OVER MULTIPLE UPSTREAM CHANNELS WITHIN A CABLE MODEM SYSTEM, filed 10 Jun. 1999 by Glenn E. Lee, et al., which application is incorporated herein by reference in its entirety for all purposes.BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The present invention relates to transmitting data over existing cable television plants using cable modems. More specifically, it relates to upstream transmission of data from the cable modem to the head end. [0004] 2. Description of the Related Art [0005] The cable TV industry has been upgrading its signal distribution and transmission infrastructure since the late 1980s. In many cable television markets, the infrastructure and topology of cable systems now include fiber optics as part of its signal transmission ...

AI Technical Summary

Benefits of technology

[0022] In a further aspect, the first upstream channel is obtained from information in the downstream channel input to the cable modem, and the second upstream channel is obtained from the information in the downstream channel input to the cable modem. In one embodiment, a first type of data are transmitted over the first upstream channel, and a second type of data are transmitted over the second upstream channel. In another embodiment, data are transmitted over the first upstream channel when it is less congested than the second upstream channel, and data are transmitted over the second upstream channel when it is less congested than the first upstream channel. In another aspect, data are primarily transmitted over the first upstream channel, and data are transmitted over the second upstream channel to facilitate load balancing.

[0026] The present invention has several associated advantages. For example, the present invention provides mechanisms for configuring a cable modem to transmit on two or more channels. This features provides a significant increase in bandwidth over the single upstream channel configuration. Additionally, if one of the multiple upstream channels of a cable modem becomes unable to transmit data, another upstream channel may take over transmission. Thus, the present invention may increase the reliability of data transmission.

Problems solved by technology

However, the cable system did not have the equipment necessary for sending signals from subscribers to the head end, known as return or upstream signal transmission.

In addition, because cable modems were not used, the head end of pre-HFC cable systems did not contain a CMTS.

Amplifiers decrease a cable system's channel capacity, degrade the signal quality, and are susceptible to high maintenance costs.

Although a 10 Mbps data transmission bandwidth is adequate for transmitting certain types of data that do not require large amounts of bandwidth (e.g., file transfers), a 10 Mbps bandwidth is inadequate for transmitting data that requires a larger amount of bandwidth (e.g., real time voice and video conferencing).

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