The new Cisco IOS Firewall for Internet Protocol version 6 (IPv6) provides stateful inspection to both existing IPv4 and IPv6 traffic on a single interface for enhanced performance, along with better management of the IPv6 migration process.
Causes of Muscle contractions that are rare. The offical US government definition of a rare disease is one that affects 200,000 people or less. The following causes of Muscle contractions appear in the population at a rate of less than 200,000 people per year in the USA: 1  Alpers Syndrome-involuntary muscle contraction. 2  Fahr's Syndrome-athetosis. 3  Ramsay Hunt syndrome Type II-involuntary muscle contraction.
Most commonly, the cramps are caused by the bodyâs shortage of minerals, such as calcium and magnesium. A shortage of acetic acid can also cause cramps. The body uses acetic acid to produce acetylcholine, which is essential for leg muscle contractions. This is why mustard is effective for leg cramp relief.