Content-based forwarding/filtering in a network switching device

In a switching device, a method for processing a data packet having a header portion and a payload portion, the method comprising the steps of:

• receiving the data packet;
• identifying a position in the payload portion of the data packet in accordance with an offset value;
• comparing information located at the identified position with a comparator value to generate a filter outcome;
• and
• forwarding the data packet or not in accordance with the filter outcome.

A switching device for forwarding a data packet having a header portion and a payload portion, comprising:

• an input for receiving the data packet;
• and
• a filter coupled to the input for identifying a position in the payload portion of the data packet in accordance with an offset value and comparing information located at the identified position with a comparator value to generate a filter outcome;
• wherein packet forwarding information is generated in accordance with the filter outcome and the packet is forwarded on an output accordance with the packet forwarding information.

In a switching device, a method for forwarding a data packet having a header portion and a payload portion, the method comprising the steps of:

• receiving the data packet;
• identifying a position in the payload portion of the data packet in accordance with an offset value;
• comparing information located at the identified position with a comparator value to generate a filter outcome;
• generating packet forwarding information in accordance with the filter outcome;
• and
• forwarding the packet in accordance with the packet forwarding information.

A switching device for forwarding a data packet having a header portion and a payload portion, comprising:

• an input for receiving the data packet;
• a memory for storing an offset value to identify a position in either the header portion or the payload portion of the data packet;
• and
• a filter coupled to the input and the memory for identifying a position of the data packet in accordance with the offset value and comparing information located at the identified position with a comparator value to generate a filter outcome;
• wherein packet forwarding information is generated in accordance with the filter outcome and the packet is forwarded on an output in accordance with the packet forwarding information.

In a switching device, a method for forwarding a data packet having a header portion and a payload portion, the method comprising the steps of:

• storing on the switching device an offset value to identify a position in either the header portion or the payload portion of the data packet;
• receiving the data packet;
• identifying a position in the payload portion of the data packet in accordance with the offset value;
• comparing information located at the identified position with a comparator value to generate a filter outcome;
• generating packet forwarding information in accordance with the filter outcome;
• and
• forwarding the packet in accordance with the packet forwarding information.