Apple 034-2351_Cvr manual IPv6 Support

IPv6 Support 7

IPv6 is short for “Internet Protocol Version 6."IPv6 is the Internet’s next-generation protocol designed to replace the current Internet Protocol, IP Version 4 (IPv4, or just IP).

The current Internet Protocol is beginning to have problems coping with the growth and popularity of the Internet. IPv4’s main problems are:

•Limited IP addressing.

IPv4 addresses are 32 bits, meaning there can be only 4,300,000,000 network addresses.

•Increased routing and configuration burden.

The amount of network overhead, memory, and time to route IPv4 information is rapidly increasing with each new computer connected to the Internet.

•End-to-end communication is routinely circumvented.

This point is actually an outgrowth from the IPv4 addressing problem. As the number of computers increases and the address shortages become more acute, another addressing and routing service has been developed, Network Address Translation (NAT), which mediates and separates the two network end points. This frustrates a number of network services and is limiting.

IPv6 fixes some of these problems and helps others. It adds improvements in areas such as routing and network auto-configuration. It has increased the number of network addresses to over 3 x1038, and eliminates the need for NAT. IPv6 is expected to gradually replace IPv4 over a number of years, with the two coexisting during the transition.

This chapter lists the IPv6 enabled services used by Mac OS X Server, gives guidelines for using the IPv6 addresses in those services, and explains IPv6 address types and notation.

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