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:
“The contention that a standing army and navy is the best security of peace is about as logical as the claim that the most peaceful citizen is he who goes about heavily armed. The experience of every-day life fully proves that the armed individual is invariably anxious to try his strength. The same is historically true of governments. Really peaceful countries do not waste life and energy in war preparations, with the result that peace is maintained.”
—Emma Goldman (1869–1940)
“A well-regulated militia being necessary to the security of a free State, the right of the people to keep and bear arms shall not be infringed.”
—Second Amendment, U.S. Constitution (1791)
“There is one safeguard known generally to the wise, which is an advantage and security to all, but especially to democracies as against despots. What is it? Distrust.”
—Demosthenes (c. 384–322 B.C.)