System and method for multidimensional data compression

• US 20030033435A1
• Filed: 07/16/2002
• Published: 02/13/2003
• Est. Priority Date: 07/17/2001
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Hanner, Brian D.
• Granted Patent: US 7,191,468 B2
• Time in Patent Office: Days
• US Class Current: 709/247
• CPC Class Codes: H04L 63/0236 Filtering by address, protocol, port number or service, e.g. IP-address or URL
• CPC Class Codes: H04L 69/04 Protocols for data compression, e.g. ROHC

Abstract

A computer-based method and system for performing header filtering of data is presented The method comprises compressing the header of a data packet to obtain a header signature and determining if the header signature matches a known header signature. If the header signature is determined to have a match, then the header signature is identified as a known header signature. A header signature may be generated using a multidimensional data compression algorithm. A compression algorithm comprises obtaining the data bits contained in each field of a typical header. Then, a header-field group that corresponds uniquely to each field is determined. Each field is replaced with the header-field group of the corresponding data bits of the field and concatenated to create a header signature.

Claims

1. A computer-based method for performing header filtering of data, the method comprising:

(a) compressing the header of a data packet to obtain a header signature;

(b) determining if the header signature matches a known header signature; and

(c) if the header signature is determined to have a match, then identifying the header signature as a known header signature.

2. The method of claim 1 wherein the header comprises a plurality of fields corresponding to parameters of the data packet.

3. The method of claim 2 wherein the header signature comprises a plurality of header-field groups that correspond to the plurality of fields.

4. The method of claim 2 wherein the header is compressed using a compression algorithm that comprises:

(a) obtaining the data bits contained in each field;

(b) determining a header-field group that corresponds uniquely to each field, wherein determining the header-field group comprises using a lookup table;

(c) representing each field with a header-field group of the corresponding predetermined combination; and

(d) concatenating each header-field group to create a header signature.

5. The method of claim 1 further comprising storing known header signatures in a lookup table.

6. The method of claim 1 further comprising flagging data packets having header signatures identified as known header signatures to be filtered.

7. A computer-based method for scanning data, the method comprising:

(a) receiving a stream of data packets, each data packet comprising a header and a payload, each header comprising a plurality of fields;

(b) determining a header-field group for each of the plurality of fields in each header;

(c) concatenating each header-field group to create a header signature for each header; and

(d) determining that a header signature is a known header signature if the header signature matches a header signature from a predetermined list of header signatures.

8. The method of claim 7 further comprising flagging known header signatures identified by comparison to the list of header signatures for filtering.

9. The method of claim 7 wherein determining the header-field group comprises:

(a) obtaining the data bits contained in each field

(b) using a lookup table to determine a header-field group that corresponds uniquely to each field; and

(c) representing each field with the corresponding header-field group of the corresponding predetermined combination.

10. A method for identifying the source of data packet, the method comprising:

(a) receiving a data packet at a packet filtering unit, the data packet having a header and a payload;

(b) identifying a plurality of fields in the header of the data packet;

(c) determining a header-field group for each field in the header by reading the data bits in each field and cross-referencing the data bits in a first lookup table of header-field groups;

(d) concatenating the header-field groups to yield a header signature

(e) determining if the header signature matches any header signature in a list of header signatures; and

(f) identifying the header signature as a known header signature if the header signature matches any header signature in the list of header signatures in a second lookup table.

11. The method of claim 10 further comprising if the header signature is determined to be a known header signature, then flagging the data packet corresponding to the header signature.

12. The method of claim 10 wherein the list of header signatures is stored in a lookup table.

13. The method of claim 10 wherein one of the fields is a destination internet protocol address field.

14. The method of claim 10 wherein one of the fields is a source internet protocol address field.

15. The method of claim 10 wherein one of the fields is a transport protocol address field.

16. The method of claim 10 wherein one of the fields is a destination port address field.

17. The method of claim 10 wherein one of the fields is a source port address field.

18. The method of claim 10 wherein one of the fields is an internet control message protocol type and code field.

19. A system for header filtering of data packets, the system comprising:

(a) a lookup table in a memory operable to store known header signatures; and

(b) a packet-filtering unit connected to a network and coupled to the memory, the packet-filtering unit operable to;

(i) compress the header of a data packet to obtain a header signature;

(ii) compare the header signature to known header signatures in the lookup table; and

(iii) identify the header signature as a known header signature if the header signature is determined to have a match.

20. The system of claim 19 wherein the header is compressed using a compression algorithm, the compression algorithm comprising:

(a) obtaining the data bits contained in each field;

(b) determining a header-field group that corresponds uniquely to each field, wherein determining the header-field group comprises using the lookup table;

(c) representing each field with a header-field group of the corresponding predetermined combination; and

(d) concatenating each header-field group to create a header signature.

21. A system for identifying the source of data packet, the system comprising:

(a) a lookup table in a memory operable to store known header signatures; and

(b) a packet-filtering unit connected to a network and coupled to the memory, the packet-filtering unit operable to;

(i) receive a data packet having a header and a payload;

(ii) identify a plurality of fields in the header of the data packet;

(iii) determine a header-field group for each field in the header by reading the data bits in each field and to cross-reference the data bits in the lookup table of header-field groups;

(iv) concatenate the header-field groups to yield a header signature

(v) determine if the header signature matches any header signature in a list of header signatures; and

(vi) if the header signature matches any header signature in the list of header signatures, identify the header signature as a known header signature.

22. The system of claim 21 further comprising a filter for filtering a data packet if the header signature of the data packet is determined to be a known header signature.