Assigning cell data to one of several processors provided in a data switch

A method of assigning a cell to one of a plurality of processors comprised in an internet service node (ISN), said method comprising the steps of:

• (a) configuring a content addressable memory (CAM) comprising a plurality of locations, each of said plurality of locations having a mask, a search field and an output field, said CAM being designed to receive an input value and compare said input value with data in said search field at bit positions specified by said mask for each of said plurality of locations,
• said search field, said mask and said output field of a first location comprised in said plurality of locations being configured with first a first search value, a first mask value and a first output value respectively, said search field, said mask and said output field of a second location comprised in said plurality of locations being configured with a second search value, a second mask and a second output value respectively,
• wherein said first search value, said first mask value and said first output value are not equal to said second search value, said second mask and said second output value respectively and wherein said first output value and said second output value contain data identifying one or more processors comprised in said plurality of processors;
• (b) receiving said cell in said ISN;
• (c) providing data in said first cell as said input value to said CAM;
• (d) receiving as an output of said CAM the data stored in said output field of a location if the corresponding search field matches said input value at the bit positions specified by the corresponding mask;
• and
• (e) assigning said cell to a processor identified by said output received in step (d).

An internet service node (ISN) for processing a packet comprising a sequence of cells including a header cell, said ISN comprising:

• a plurality of processors;
• a content addressable memory (CAM) containing a plurality of locations, each of said plurality of locations having a mask, a search field and an output field, said CAM being designed to receive an input value and compare said input value with data in said search field at bit positions specified by said mask for each of said plurality of locations, said CAM being designed to generate as output the data stored in said output field if there is a match with the corresponding location, said search field and said mask of said location being configured with data identifying packets suitable for processing by one or more of said plurality of processors, said output field being configured with data identifying one or more processors suitable for processing a corresponding packet;
• and
• an assignment logic for receiving said header cell and providing data from said header cell as said input value of said CAM, whereby the output of said CAM identifies one or more processors suitable for processing said packet, said assignment logic assigning all of said sequence of cells to said one or more processors according to said output of said CAM,
• wherein said packet is processed by a suitable processor.