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.
Muscle spasms and cramps. Cramps are caused by muscle spasms, involuntary contractions of one or more muscles. In addition to the foot and calf muscles, other muscles prone to spasms include the front and back of the thigh, the hands, arms, abdomen and muscles along the ribcage.uscle cramps can have many possible causes. They include: 1  Poor blood circulation in the legs. 2  Overexertion of the calf muscles while exercising. 3  Insufficient stretching before exercise.