Cisco Technology, Inc.

Pawel Piotr Sowinski

Tong Liu

John T Chapman

Robert Goguen

De Fu Li

Hang Jin

Carlos M Pignataro

Nagendra Kumar Nainar

Alon Shlomo Bernstein

Jiening Ao

Michael J Healy

Daniel W Crocker

Vengada Prasad Govindan

Yie-Fong Dan

John Skrobko

William Beebee

James An

Chad Mikkelson

Nicos Achilleoudis

Brian Patrick Bresnahan

Lin Su

DeFu Li

Robert J Goguen

Multipoint seamless Bi-directional Forwarding Detection (BFD) may be provided. First, a discriminator and data identifying a headend device may be received by a node from the headend device. The discriminator may be received over a point-to-multipoint pseudowire between the node and the headend device. Next, the node may start a reflector session in response to receiving the discriminator. The reflector session may correspond to the discriminator and the data identifying the headend device. The reflector session may then receive a control packet from the headend device and determine that the control packet includes the discriminator. The control packet may be received over the point-to-multipoint pseudowire. Next, the reflector session on the node may send a reply packet to the headend device in response to determining that the control packet includes the discriminator. The reply packet may be sent over a unicast pseudowire between the node and the headend device.

Multipoint seamless bi-directional forwarding detection

An example method for Downstream External Physical Interface (DEPI) in Data Over Cable Service Interface Specification (DOCSIS) 3.1 network environments is provided and includes generating, at a Converged Cable Access Platform (CCAP) core, a DEPI-Packet Streaming Protocol (PSP) pseudo-wire (PW) packet including a PSP sub-layer header having a same length for a Quadrature Amplitude Modulation (QAM) channel and an Orthogonal Frequency-Division Multiplexing (OFDM) channel in the DOCSIS network environment, and transmitting the DEPI-PSP PW packet over a DEPI interface to a remote physical layer (R-PHY) entity.

Downstream external physical interface transport in DOCSIS 3.1 network environments

An example method for determining and managing upstream profiles in Data Over Cable Service Interface Specification (DOCSIS) 3.1 network environments is provided and includes determining, at a Converged Cable Access Platform (CCAP) core, channel conditions independent of any channel effect over a hybrid fiber coaxial (HFC) network between a remote physical layer (R-PHY) entity coupled to the CCAP core and a cable modem (CM) in the DOCSIS 3.1 network environment, and assigning an upstream profile to the CM based on the channel conditions. In specific embodiments, the channel conditions include signal to noise ratio (SNR), modulation error ratio (MER) or group delay. In some embodiments, assigning the upstream profile includes determining a quadrature amplitude modulation (QAM) order based on the SNR or MER, and determining a pilot pattern based on the group delay, the combination of the QAM order and the pilot pattern identifying the upstream profile.

Determining and managing upstream profiles in DOCSIS 3.1 network environments

Presented herein are techniques for detection and avoidance of interference in a telecommunications network. In one example, a cable modem termination system (CMTS) is configured to receive upstream traffic from a plurality of cable modems. The CMTS detects collision characteristics resulting from substantially simultaneous transmissions from different combinations of the cable modems. Based on the detected collision characteristics, the CMTS designates/identifies collision groups for each of a plurality of the cable modems. After designation of the collision groups, the CMTS schedules upstream transmissions by the plurality of cable modems such that cable modems within the same collision group do not transmit within a same time frame and such that two or more cable modems that are not within the same collision group may transmit within a same time frame.

Interference detection and avoidance in a telecommunication network

A method is provided in one example and includes segmenting a plurality of cable modems into a plurality of groups; identifying traffic being received or transmitted by each of the plurality of cable modems that is below a threshold; and determining whether to move each of the plurality of cable modems into a low-power mode based, at least in part, on the traffic being received or transmitted by each of the plurality of cable modems.

Apparatus, system, and method for providing energy management, profiles, and message blocks in a cable service environment

A system includes a forwarding engine to schedule when replicas of a received multicast packet are forwarded towards one or more multicast recipients. The system also includes an egress interface device to replicate the multicast packet and forward the multicast packet replica towards the one or more multicast recipients when prompted by the forwarding engine based on the scheduling.

Distributed multicast packet replication with centralized quality of service

In one embodiment, a Cable Modem Termination System (CMTS) generates a bandwidth grant message corresponding to a time segment. The CMTS identifies a portion of the time segment to be assigned according to received bandwidth request messages originating from downstream cable modems. The CMTS determines whether a remaining portion of the time segment can accommodate more than N broadcast contention slots, and if so, selects at least one of the cable modems for receiving an upstream bandwidth boost.

CMTS upstream channel bandwidth scheduler

In one example, a Cable Modem Termination System (CMTS) sends first bandwidth allocation messages to a first upstream transmit interface on a cable modem and send second bandwidth allocation messages to a second upstream transmit interface on the cable modem. The bandwidth allocation messages indicate transmit windows for the cable modem to range over the interfaces. The transmit windows included in the first bandwidth allocation messages are spaced based on receipt of ranging requests from the second upstream transmit interface, and the transmit windows included in the second bandwidth allocation messages are spaced based on receipt of ranging requests from the first upstream transmit interface.

Multi-channel ranging for a cable modem

An M-CMTS compatible UEQAM device implements circuitry to identify and analyze MAP message in the data stream sent from the M-CMTS Core with respect to timing information embedded in those messages. The improved UEQAM will then create a specific message as an extension to DEPI to communicate that information to the M-CMTS Core. The M-CMTS Core will employ that analysis to automatically adjust MAP message advance time to reduce delay and thus improve system performance. This invention will provide a closed-loop between the M-CMTS Core and the UEQAM where valuable transmission information will periodically be fed back from UEQAM-to-M-CMTS Core in real-time.

Map message expediency monitoring and automatic delay adjustments in M-CMTS

In one embodiment, a first ranging timing description describing at least a duration of time during which a subject cable modem (CM) may burst and a duration of time during which the subject CM and other CMs in a multiple access network are not permitted to burst is translated into a second ranging timing description describing a duration during which a burst from the subject CM is expected to be received by a cable modem termination system (CMTS). The CMTS is conditioned to receive a burst from the subject CM during the duration of time described by the second ranging timing description. A timing offset is determined from at least an actual time a burst from the subject CM is received by the CMTS and the duration of time during which the subject CM and other CMs in the multiple access network are not permitted to burst to produce a determined timing offset. The determined timing offset is reported to compensate for delay in the multiple access network and the subject CM.

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Sudbury, MA, United States of America

Pawel Piotr Sowinski