Cisco Technology, Inc.

Marvell Asia Pte., Ltd.

Jeffrey Ym Wang

Michael R Smith

Ali Golshan

Dileep Kumar Devireddy

Saravanakumar Rajendran

Pradeep Kumar Kathail

Chandrashekhar Appanna

Douglas Alan Gourlay

Karthik Raviprakash

Sagar Ray

Abhijit Patra

Roger Antoine Karam

Prashant Gandhi

Milton Y Xu

Venkatesh Janakiraman

Neelima Mehta

Peram Marimuthu

Michael Smith

A variable gain amplifier system includes a variable gain amplifier circuit configured to receive an input signal, apply a gain to the input signal, and generate an output signal in accordance with the gain applied to the input signal. The variable gain amplifier circuit is further configured to receive a gain control signal and a bandwidth control signal. A control module is configured to generate the gain control signal to adjust the gain of the variable gain amplifier circuit and generate, separately from the gain control signal, the bandwidth control signal to adjust a bandwidth of the variable gain amplifier circuit by selectively varying an amount of inductance contributed by an inductor circuit of the variable gain amplifier circuit.

Variable gain amplifier system including separate bandwidth control based on inductance contribution

The present invention is directed electrical circuits. According to a specific embodiment, the present invention provides a variable gain amplifier that includes a first switch, which includes drain terminal coupled to an inductor. A second switch is configured in parallel to the inductor, and the resistance value of the second switch is adjustable in response to a control signal. There are other embodiments as well.

Constant-bandwidth linear variable gain amplifier

An adjunct network device includes several ports, an uplink interface, and an adjunct forwarding engine coupled to the ports and the uplink interface. A first port is configured to receive a packet, which includes a destination address. The adjunct forwarding engine is configured to send the packet to the uplink interface if the destination address is not associated with any of the ports. The packet is sent to one of the ports if the destination address is associated with the one of the ports.

Determining when to switch to a standby intelligent adjunct network device

A blade router for increased interface scalability is provided. The blade router may address interface scalability by having each of the linecards manage its interfaces locally and may use the concept of virtual and local interfaces for intelligent forwarding. The blade router may appear as a single router from the customer perspective during configuration. For some embodiments, two virtual interfaces may be used, one for regular interface traffic and another for Network Address Translation (NAT)-enabled interface traffic.

Blade router with NAT support

Intelligent adjunct network device

A blade switch for increased interface scalability is provided. The blade switch may address interface scalability by having each of the switch linecards manage its interfaces locally and may use the concept of virtual and local interfaces for intelligent forwarding. The blade switch may appear as a single network switch having a single bridge ID from the network perspective during operation and from the customer perspective during configuration.

Blade switch with scalable interfaces

A method may involve: receiving a packet (e.g., via a port or uplink interface in a satellite switch) and conveying the packet between one or more ports and one of several uplink interfaces. The one or more ports and the uplink interface are associated with each other. The association can be independent of VLAN (Virtual Local Area Network). As an example, such a method can involve: receiving a first packet via a first port; conveying the first packet to a distribution-layer via a first uplink interface; receiving a second packet via a second port; and conveying the second packet to the distribution-layer via a second uplink interface, where the first uplink interface is associated with the first port and the second uplink interface is associated with the second port. In some embodiments, ports and uplink interfaces are associated by being assigned to the same virtual linecard.

Port-based loadsharing for a satellite switch

Systems and method for providing redundancy of communications and/or inline power to a powered Ethernet device are disclosed. A redundancy device is configured to receive in-line data and/or power from a plurality of Ethernet relay uplinks and to monitor communications between the relay uplinks. One of the relay uplinks is established as an active state uplink and passes data and/or power to the power device. Responsive to a switchover communication from a redundant uplink, the redundancy device establishes the redundant uplink as the active uplink, thereby passing data and/or power from the redundant uplink to the power device. The relay uplinks may use packet-based communication to sense when there is a failure in a link, and replace a failed device with a redundant device.

Wiring closet redundancy

Method and system for providing access layer satellite architecture in a data network including receiving a data packet from an access layer network device, the data packet including a Virtual Local Area Network (VLAN) identifier associated with a port on the access layer network device, performing a route lookup procedure based on the received data packet to determine a destination of the data packet, updating an ARP table with a Media Access Control (MAC) address associated with the VLAN identifier and the port of the received data packet, and transmitting the data packet to a destination network device, is disclosed.

Data forwarding in a layer three satellite network

Method and devices are provided to form virtual switches for data networks. As noted above, the term 'switch' as used herein will apply to switches, routers and similar network devices. Each virtual switch acts as a single logical unit, while encompassing at least two physical chassis. Accordingly, each virtual switch may be treated as a single point of management. Each virtual switch includes a master chassis and at least one slave chassis. The master chassis is configured to control the slave chassis. The master chassis includes at least one master supervisor card and the slave chassis includes at least one slave supervisor card. The master chassis and the slave chassis communicate via a virtual switch link according to a virtual switch link protocol.

Virtual network device

Only one point to multipoint virtual circuit (p2mp VC) is used within a router to handle all of the sources for a particular multicast group when other particulars of the multicast group are identical within that router. The router receiving a multicast packet for a particular multicast group identifies the source and the group number by reading fields of the incoming packet, identifies the input port of the router, and identifies the output port list. The input port of the router, the group number G, and the output port list are used by the router in establishing and identifying a point to multipoint VC within the router. The invention identifies all packets arriving at that particular input port, having the same multicast group number G, and having the same output port list, and transfers them to the identified VC. The VC is associated in the routing table with the output list of ports from which copies of the multicast packet are transmitted. Accordingly, only one VC is needed to transfer packets arising from any source of the multicast group so long as the multicast packets arrive on the same port of the router and have the same output port list.

Growing community of inventors

Saratoga, CA, United States of America

Jeffrey Ym Wang