Embedded communications system and method

• US 7,725,595 B1
• Filed: 05/24/2005
• Issued: 05/25/2010
• Est. Priority Date: 05/24/2005
• Status: Active Grant

• Current Assignee: The United States of America As Represented By The Secretary of Agriculture
• Original Assignee: the united states of america as represented by the secretary of the navy
• Inventors: Geissler, William Karl, McEachen, John Colin
• Primary Examiner(s): Abdullahi; Salad
• Assistant Examiner(s): SHIU, HO T
• Application Number:
  US11/138,699
• Time in Patent Office: 1,827 Days
• Field of Search: None
• US Class Current: 709/235
• CPC Class Codes: H04L 1/0061 Error detection codes
• CPC Class Codes: H04L 1/0079 Formats for control data H04L1/16 takes precedence; training sequences H04L25/00 and H04L27/00
• CPC Class Codes: H04L 1/1664 the supervisory signal being transmitted together with payload signals; piggybacking
• CPC Class Codes: H04L 1/1854 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 69/16 Implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP]
• CPC Class Codes: H04L 69/161 Implementation details of TCP/IP or UDP/IP stack architecture; Specification of modified or new header fields
• CPC Class Codes: H04L 69/163 In-band adaptation of TCP data exchange; In-band control procedures

Abstract

A method and system for steganography and steganalytic techniques are provided for effecting embedded communications in a variety of communication environments. One aspect may include an embedded transmitter for inserting embedded data into a packet and an embedded receiver for receiving the packet via, for example, a packetized communication network such as the Internet. Various aspects of the present invention provide robust communications with optimized throughput and may include various error handlers to maximize performance and ensure transfer of incorrupt data. A method for identifying and blocking embedded communications is also provided.

Claims

1. A system for embedded communication in a communication network, the system comprising:

an embedded transmitter, the embedded transmitter for performing a method comprising;

replacing overt data of at least one data field of a packet with embedded data;

calculating a first embedded checksum value of the embedded data;

comparing the first embedded checksum value to a first overt checksum value;

replacing the first overt checksum with a flag value, if the comparison is equal;

replacing a first overt checksum value with the first embedded checksum value, if the comparison is unequal;

transmitting the packet via the communication network; and

an embedded receiver, the embedded receiver for performing a method comprising;

receiving the packet;

calculating a second embedded checksum value for the embedded data;

if the checksum comparison is equal or a flag value is detected;

processing the embedded data or forwarding the embedded data to a predetermined embedded data handler; and

generating an embedded acknowledgment for the packet, the embedded acknowledgment having an acknowledgment number associated with the packet;

else if the checksum comparison is unequal;

discarding the current received packet; and

repeatedly regenerating an embedded acknowledgment for the last packet successfully received in proper sequence order until a predetermined event occurs.

2. The system of claim 1, further comprising at least one error handler.

3. The system of claim 2, wherein the at least one error handler further comprises at least one element selected from a group consisting essentially of a packet error handler;

a checksum collision handler; and

an embedded acknowledgment error handler.

4. A method of embedded communication via a communication network, the method comprising steps of:

replacing overt data of a data field of a packet with embedded data;

calculating a first embedded checksum value of the embedded data;

comparing the first embedded checksum value to a first overt checksum value;

replacing the first overt checksum with a flag value, if the comparison is equal;

replacing a first overt checksum value with the first embedded checksum value, if the comparison is unequal;

transmitting the packet via the communication network;

receiving the packet;

calculating a second embedded checksum value for the embedded data;

if the checksum comparison is equal or a flag value is detected;

processing the embedded data or forwarding the embedded data to a predetermined embedded data handler; and

generating an embedded acknowledgment for the packet, the embedded acknowledgment having an acknowledgment number associated with the packet;

else if the checksum comparison is unequal;

discarding the current received packet; and

repeatedly regenerating an embedded acknowledgment for the last packet successfully received in proper sequence order until a predetermined event occurs, then retransmitting the next-in-sequence packet.

5. The method of claim 4, further comprising a step of providing an embedded acknowledgment error routine.

6. The method of claim 4, further comprising a step of providing a checksum collision routine.