Search tree algorithms

1. An information packet preclassification method comprising:

receiving via an input interface port a packet of information;

differentiating the packet into segments using a packet parsing engine (PPE);

using a PPE decision tree random access memory (RAM) including a logic decision tree

with multiple levels;

comparing segments in the packet to a node at a tree level, wherein each node includes

a plurality of node reference segments and corresponding node comparison operators, said comparing segments includes making a comparison between a first reference segment in the packet and node reference segments selected from a group consisting of a second reference segment in the packet and a predetermined segment value stored in memory;

in response to comparing the segments to the nodes, the PPE assigning a plurality of classification attributes to the packet: packet;

forwarding the packet to a processor for processing in response to a classification attribute;

and

using a user interface (UI) to select segments in the packet to be written.

2. The method of claim 1 further comprising, prior to receiving the packet, using a user interface (UI):

selecting reference segments for a node;

selecting comparison operators for a node;

selecting branches between nodes on different tree levels; and,

selecting the number of tree levels.

3. The method of claim 2 further comprising:

prior to receiving the packet, using the UI to select segments in the packet to be compared.

4. A system for preclassifying information packets, the system comprising:

an input interface with a plurality of ports to accept information packets;

a packet parsing engine (PPE) connected to a corresponding port to receive a packet and differentiate the packet into segments, the PPE including:

a packet random access memory (RAM) for storing packet segments;

a decision tree RAM for storing a logic decision tree with multiple tree levels,

where

each node includes a plurality of node reference segments and corresponding node comparison operators;

a controller having an interface for accessing the packet RAM and decision tree RAM, for

comparing segments in the packet to nodes in the decision tree, and assigning a classification to the packet;

a classification database having an interface to accept classification pointers from the plurality of PPEs, and an output to supply classification attributes for packets in response to receiving the classification pointers;

a processor having an interface to receive packets and classification attributes associated with the packets, the processor supplying processed packets responsive to their respective classification attributes; and

a user interface (UI) configured to permit selecting of segments in a packet to be written.

5. The system of claim 4 wherein the PPE controller derives a plurality of classification pointers for a packet; and,

wherein the classification database assigns a plurality of classification attributes to the packet, in response to receiving the plurality of classification pointers.

6. The system of claim 4 wherein the PPE controller makes a comparison between a first reference segment in the packet and node reference segments selected from a group consisting of a second reference segment in the packet and a predetermined segment value stored in the logic tree RAM.

7. The system of claim 4 wherein the UI is connected to the decision tree RAM for configuring the decision tree.

8. The system of claim 7 wherein the UI permits writing reference segments and comparison operators into a tree level node, selecting the number of tree levels, selecting inter-tree levels branches between nodes on different tree levels, selecting classification pointers for key nodes, and selecting the number of classification pointers per key node.