Cisco Technology, Inc.

Chrisanto Leano

Sunil Khaunte

Alon Shlomo Bernstein

Guenter E Roeck

Mark E Millet

Kartik S Chandran

Jerry D Goodrich

Kelly Schaefer

Son Truong Nguyen

Alejandro Schwartzman

De Fu Li

Hui Sun

James An

James Clark

Keil Brewer

John J Downey

Methods and devices are provided for regulating traffic on a network. According to some aspects of the invention, if a subscriber's upstream traffic exceeds a predetermined level over a first period of time, the subscriber's quality of service is adjusted without requiring the subscriber to re-register. According to some embodiments, a first token bucket is used to determine whether the subscriber's upstream traffic exceeds the predetermined level over the first period of time. In some such embodiments, the first token bucket is used to control the burst size of another token bucket, depending on the subscriber's upstream traffic during the first period of time.

Methods and devices for regulating traffic on a network

Disclosed are apparatus and methods for managing upstream channels on a per cable modem basis. In certain embodiments, one or more thresholds are defined for each of a plurality of upstream logical channels of a headend system for receiving data from a plurality of cable modems (or other types of access nodes). Each defined threshold corresponds to a measurable parameter of the corresponding upstream logical channel. One or more metrics are collected for each cable modem of each upstream logical channel. It is determined whether to downgrade a selected cable modem to a selected one of the logical channels that has a lower performance level than the selected cable modem's current logical channel. Such downgrade determination is based on whether the selected cable modem's collected one or more metrics have failed a condition of the one or more defined thresholds and whether a percentage of a total of the cable modems of such current logical channel that have failed a condition for the one or more defined thresholds is less than a predefined percentage level. The selected cable modem is then caused to move from the current logical channel to the selected logical channel when the percentage of the total cable modems that have failed is below a predefined level if such selected logical channel is available. Otherwise, the current logical channel's modulation profile may be altered when the percentage of the total cable modems that have failed is above (or equal to) the predefined level.

Apparatus and methods for moving cable modems between upstream channels

A method of using DOCSIS 1.1 features to allow the addition of ISPs and QOS levels to a single cable modem without having to modify the CMTS is described in the various figures. Instead of using the SID of a data packet to determine the VPN tag of a data packet (DOCSIS 1.0), a service flow is used to identify the appropriate tag. This is done using the DOCSIS 1.1 configuration file. By doing so, the need for creating additional sub-interfaces in the cable modem interface does not arise. Instead, the configuration is modified at the provisioning server, i.e., the DHCP/TFTP server.

Method and apparatus for mapping an MPLS tag to a data packet in a headend

Methods and apparatus for disabling and enabling the receiver circuitry of a cable modem connected to a cable network headend are described. The cable network headend transmits a message to the cable modem to disable the receiver circuitry when a cable network headend determines that the cable modem is idle. The cable modem listens for messages on the cable network during activation windows between periodic intervals. Messages arriving during these activation windows can enable the receiver circuitry of the cable modem as well as synchronize the clocks of the cable network headend and the cable modem. The cable modem can also self enable its receiver circuitry and inform the cable network headend of its enabled state.

Methods and apparatus for enabling and disabling cable modem receiver circuitry

A system for testing a cable network during normal operation interleaves test signals with live data traffic. Installed cable modems are used to generate the test signals. During live communication, such modems send upstream data at allotted time periods. Periodically, there are time slots when no modem is transmitting on the network. During these times, specific modems may be directed to transmit specific test signals. A controller such as a cable modem termination system directs specific modems to transmit signals at defined frequencies and powers during specific time slots. In this manner, the system can monitor the frequency response of the cable network at various locations, and thereby determine 'on-the-fly' when maintenance or modification is required.

Cable plant certification procedure using cable modems

Methods, apparatus, and computer-readable media are disclosed for creating a virtual lookahead upstream receiver in a single physical upstream receiver in a CMTS, thereby avoiding having to dedicate an upstream receiver strictly for lookahead capability. A lookahead receiver is used to determine whether a potential alternative frequency is better than the frequency presently being used. A physical upstream receiver is assigned to operate under a set of operational parameters associated with a logical lookahead receiver during a particular time slot. The logical receiver receives upstream data from a selected test modem using an alternative upstream frequency. It is then determined whether the alternative upstream frequency is preferable over the frequency presently being used. If so, the physical receiver is configured to operate normally under the set of operational parameters associated with the logical receiver. At this stage, all modems in a particular group, including the selected modem, hop over to the alternative frequency. The physical receiver can be divided into any number of logical receivers.

Method and apparatus for creating virtual upstream channels for enhanced lookahead channel parameter testing

A technique is described for improving packet performance in an access network. The access network comprises a Head End and a plurality of nodes. The access network further includes at least one shared-access upstream channel used by the first plurality of nodes to communicate with the Head End. Propagation delay data associated with at least a portion of the plurality of nodes using the at least one upstream channel is obtained. The propagation delay data is then used to dynamically adjust the lookahead time value associated with the generating of MAP messages for the at least one upstream channel.

Technique for dynamically adjusting lookahead time for channel map messages to achieve optimal packet performance over an access network

Disclosed are a method apparatus for performing periodic ranging with a cable modem. It is determined whether an actual power level of the cable modem requires adjustment to a desired power level and it is indicated to the cable modem that it should adjust the actual power level to an adjusted power level that differs from the actual power level of the cable modem by less than or equal to a first dynamic range associated with the cable modem. In one extension of this method, the first dynamic range represents a difference between a modem dynamic range of the actual power level output by the cable modem and a head end dynamic range for recognizing the actual power level output by the cable modem.

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San Jose, CA, United States of America

Chrisanto Leano