Shifted LT Code Security Scheme for Partial Information Encryption

Area of Science:

• Information Security
• Coding Theory
• Wireless Communications

Background:

• Existing fountain code-based physical layer security struggles when legal and eavesdropping channels have comparable quality.
• This limitation compromises information security in such scenarios.

Purpose of the Study:

• To propose a novel shifted Luby transform (SLT) code security scheme for partial information encryption.
• To enhance physical layer security against eavesdropping, particularly when channel conditions are similar.

Main Methods:

• The proposed scheme involves two stages: partial information encryption transfer and degree distribution adjustment.
• Information symbols are randomly extracted and XOR encrypted with a random sequence incorporating main channel noise.
• Degree distribution is adjusted based on received symbols to increase the average degree of encoded codewords.

Main Results:

• The scheme effectively hinders eavesdroppers by making initial decoding difficult due to fewer obtained symbols and adjusted degree distribution.
• Experimental results demonstrate superior security performance compared to other LT anti-eavesdropping schemes.
• The proposed SLT scheme also exhibits reduced decoding overhead.

Conclusions:

• The shifted Luby transform (SLT) code provides robust physical layer security, even when the legitimate channel is not dominant.
• This approach offers improved information security and efficiency over existing methods.