Security
Smart cards have been advertised as suitable for personal identification tasks, because they are engineered to be tamper resistant. The chip usually implements some cryptographic algorithm. There are, however, several methods for recovering some of the algorithm's internal state.
Differential power analysis involves measuring the precise time and electrical current required for certain encryption or decryption operations. This can deduce the on-chip private key used by public key algorithms such as RSA. Some implementations of symmetric ciphers can be vulnerable to timing or power attacks as well.
Smart cards can be physically disassembled by using acid, abrasives, or some other technique to obtain unrestricted access to the on-board microprocessor. Although such techniques obviously involve a fairly high risk of permanent damage to the chip, they permit much more detailed information (e.g. photomicrographs of encryption hardware) to be extracted.
Read more about this topic: Smart Card
Famous quotes containing the word security:
“Learned institutions ought to be favorite objects with every free people. They throw light over the public mind which is the best security against crafty and dangerous encroachments on the public liberty.”
—James Madison (1751–1836)
“Those words freedom and opportunity do not mean a license to climb upwards by pushing other people down. Any paternalistic system that tries to provide for security for everyone from above only calls for an impossible task and a regimentation utterly uncongenial to the spirit of our people.”
—Franklin D. Roosevelt (1882–1945)
“The three great ends which a statesman ought to propose to himself in the government of a nation, are,—1. Security to possessors; 2. Facility to acquirers; and, 3. Hope to all.”
—Samuel Taylor Coleridge (1772–1834)