Distributed chassis architecture having integrated service appliances

摘要

A distributed virtual chassis comprises scaled-out fabric coupler (SFC) boxes. Each SFC box has fabric ports and a cell-based switch fabric for switching cells associated with a packet among the SFC fabric ports of that SFC box. Distributed line cards (DLCs) include switching DLCs and an appliance DLC (A-DLC). Each switching DLC has network ports. Each switching DLC and A-DLC has DLC fabric ports. Each switching DLC and A-DLC is connected to each of the SFC boxes. The A-DLC provides an upper layer service for packets arriving on the network ports of the switching DLCs. To forward a packet to the A-DLC, a switching DLC divides the packet into cells and distributes the cells among the SFC boxes. The SFC boxes forward the cells to the A-DLC, and the A-DLC reassembles the packet from the cells and provides the upper layer service to the packet.

主权项

1. A method of integrating an upper layer service into a distributed virtual chassis comprised of a plurality of scaled-out fabric coupler (SFC) chassis, one or more switching network elements, and a service appliance, the method comprising:
associating a network port of a switching network element with a traffic filter for a traffic flow; receiving a packet at the network port of the switching network element; determining, in response to the traffic filter, that the packet requires an upper layer service provided by the service appliance; dividing, by the switching network element in response to the traffic filter, the packet into cells each indicating that the service appliance is a destination for that cell; sending, by the switching network element, a different cell of the packet to each SFC chassis of the plurality of SFC chassis; forwarding, by each SFC chassis, the cell received by that SFC chassis to the service appliance through a cell-based switch fabric of that SFC chassis; receiving, by the service appliance, each cell of the packet from a different SFC chassis of the plurality of SFC chassis; reassembling the packet at the service appliance from the cells received from the plurality of SFC chassis; and performing the upper layer service on the reassembled packet at the service appliance.