Com21, Inc.

Other

Xerox Corporation

Arris International, Inc.

Telesis Technologies Laboratory

Mark E Laubach

Paul Baran

Sanford L Helton

Alireza Raissinia

Joseph B Lyles

Ali Raissinia

Malay M Thaker

Scott M Quinn

Kenneth Gorman

Michael John Sabin

Kathleen Nichols

Paul Gordon

Paul A Gordon

Kathleen M Nichols

A two-way cable network offering high-speed broadband communications delivered via virtual private networks over a multi-channel shared media system. Bi-directional transmission of packet to ATM cell based communications is established between a head end communication controller and a number of subscriber terminal units, whereby individual cells are prioritized and routed according to a virtual connection. Virtual connections are organized to support multiple virtual private networks in a shared media CATV system. The virtual private network to which a particular STU belongs is user selectable and has the flexibility of handling multi up/downstream channels with different MAC domains. The present invention can also handle non-ATM MAC domains via the same common ATM switch. To overcome the limited number of addresses inherent to common ATM switches, a mapping/remapping function is implemented in the port cards. Furthermore, downstream as well as upstream traffic are filtered at each STU. In one embodiment, information pertaining to downstream traffic is used to implement predictive scheduling in order to improve the timing associated with the request/grant cycle. In another embodiment, a user has the ability to select a quality of service that best suits the needs of the current application. In a further embodiment, the scheduling function is associated with each of the receivers in order to provide improved scalability.

Multi-channel support for virtual private networks in a packet to ATM cell cable system

A method in accordance with the invention allocates bandwidth, fairly and dynamically, in a shared-media packet switched network to accommodate both elastic and inelastic applications. The method, executed by or in a head-end controller, allocates bandwidth transmission slots, converting requests for bandwidth into virtual scheduling times for granting access to the shared media. The method can use a weighted fair queuing algorithm or a virtual clock algorithm to generate a sequence of upstream slot/transmission assignment grants. The method supports multiple quality of service (QoS) classes via mechanisms which give highest priority to the service class with the most stringent QoS requirements.

Method for providing integrated packet services over a shared-media network

A two-way hybrid fiber-coax cable networks offering high-speed broadband communications delivered via a cable modem service. Bi-directional transmissions of packets between the head-end controller (Cable Modem Terminal System) and cable modems (subscriber terminal units) is accomplished using a cable television Media Access Control (MAC) protocol. In Hybrid Fiber-Coax (HFC) networks, the invention provides a Reverse Path Multiplexing (RPM) function permitting the coupling of a large number of return path (plant) RF ports (return ports) to be coupled to a receiver card in the CMTS. One aspect of this invention is that one or more upstream traffic schedulers reside within the CMTS equipment with the responsibility of scheduling the upstream transmissions from cable modems. The cable modems are distributed across many return ports. The data from each cable modem must be successfully received by the head-end controller without being compromised by the effects of noise funneling. The knowledge of when a cable modem will transmit is used to open an RF switch in the RPM.

Reverse path multiplexer for use in high speed data transmissions

A method for enhancing the functionalities of a subscriber terminal unit (STU) or ADSL terminal unit (ATU) through the use of different types of application interface modules (AIMs). This is accomplished by incorporating a slot in the STU/ATU through which a detachable AIM can be inserted and electrically coupled to the STU/ATU. The STU/ATU has circuitry for determining which particular type of AIM has been inserted. Depending on the type of AIM that has been inserted in the STU/ATU (e.g., installation, telephony, diagnostics, network interface, television, etc.), management information specific to the particular AIM is sent by the STU/ATU upstream to the headend unit. In response, the headend unit provides applications service(s) to the STU/ATU, depending on the particular type of device inserted into the subscriber terminal unit.

Method and apparatus for an application interface module in a subscriber

A two-way CATV network having a radio return path. A cable headend controller is used to control downstream as well as upstream communications over the two-way CATV network. Downstream signals are sent to subscribers' cable modems through conventional coaxial cables. On the upstream side, a signal generated at a first frequency by an interactive cable modem. This signal is then sent to a transmitter applique, which converts the signal to a second frequency. The signal is then transmitted through a wireless segment at this second frequency to a receiver applique. The receiver applique converts the transmitted signal into a third frequency. In some cases, the third frequency is the same as the third frequency. Eventually, the upstream signal is sent to the headend controller. Throughout the entire upstream transmission process, the same signal is maintained; only its frequency is changed. In the various embodiments, the first, second, and third frequencies are the same; the first frequency is the same as the third frequency but not the second frequency; and the first channel can be the same as the third channel but is not the same as the second channel.

CATV network and cable modem system having a wireless return path

Bi-directional communications system in a CATV network utilizing cell-based Asynchronous Transfer Mode (ATM) transmissions. Packet data existing in any one of several different formats are first converted into ATM cells by a headend controller. Individual cells are then assigned a virtual connection by the headend controller. Based on the virtual connection, the cells can be prioritized and routed to their intended destinations. The cells are transmitted in a shared radio frequency spectrum over a standard cable TV network. A subscriber terminal unit demodulates the received RF signal and processes the cells for use in a computer. Likewise, computers may transmit packet data to their respective subscriber terminal units which are sent to the headend controller over the same CATV network. Hence, the present invention offers a flexible, effective, economic, and fully integrated multimedia bearer system granting immediate support for Internet services, traditional voice telephony, and digital video services over a CATV network.

Prioritized virtual connection transmissions in a packet to ATM cell

Method for providing integrated packet services over a shared-media

A two-way CATV network having a radio return path. A cable headend controller is used to control downstream as well as upstream communications over the two-way CATV network. Downstream signals are sent to subscribers' cable modems through conventional coaxial cables. On the upstream side, a signal generated at a first frequency by an interactive cable modem. This signal is then sent to a transmitter applique, which converts the signal to a second frequency. The signal is then transmitted through a wireless segment at this second frequency to a receiver applique. The receiver applique converts the transmitted signal into a third frequency. In some cases, the first frequency is the same as the third frequency. Eventually, the upstream signal is sent to the headend controller. Throughout the entire upstream transmission process, the same signal is maintained; only its frequency is changed. In the various embodiments, the first, second, and third frequencies are the same; the first frequency is the same as the third frequency but not the second frequency; and the first channel can be the same as the third channel but is not the same as the second channel.

Growing community of inventors

Mountain View, CA, United States of America

Mark E Laubach