Resilient hashing for forwarding packets

A method of identifying a path for forwarding a packet, the method comprising:

• in a forwarding element data plane:
• receiving a packet comprising a plurality of fields identifying a particular packet flow;
• computing a plurality of hash values from said plurality of fields identifying the particular packet flow, each hash value computed using a different hash algorithm;
• identifying an entry in a first table based on at least one field of the packet;
• retrieving from the entry in the first table a set of values identifying a location in a second table from which to retrieve a plurality of status values, the set of values comprising (i) a first value comprising a reference to a start of a sequence of status values in the second table and (ii) a second value specifying a number of status values to retrieve of the sequence of status values;
• retrieving from the location in the second table the specified plurality of status values, wherein each status value corresponds to a path of a plurality of possible paths for the packet flow and identifies whether or not the corresponding path is operational;
• using the retrieved status values and the plurality of hash values to select an operational path in the plurality of possible paths to forward the packet based on a priority scheme;
• and
• retrieving the selected path from a third table.