Taxation begins at the time of exercise. The bargain element of a non-qualified stock option is considered compensation and is taxed at ordinary income tax rates. For example, if an employee is granted 100 shares of Stock A at an exercise price of $25, the market value of the stock at the time of exercise is $50.
In the Internet Protocol version 4 (IPv4) [RFC791] there is a field called Protocol to identify the next level protocol. This is an 8 bit field. In Internet Protocol version 6 (IPv6) [RFC2460], this field is called the Next Header field. Values that are also IPv6 Extension Header Types should be listed in the IPv6 Extension Header Types registry at [IANA registry ipv6-parameters].
IPv4 and IPv6 are not directly compatible, but researchers realized that they couldn't simply flip a switch and turn off IPv4 while most of the world still depended on it. IPv6 devices are built using a process called dual stack that allows IPv6 and IPv4 to run simultaneously alongside each other.he most obvious answer is that IPv4 is out of IP addresses. IPv4 has only 4.3 billion addresses, and with PCs, smartphones, tablets, gaming systems, and just about everything else connecting to the Internet we've tapped the system dry.