TAILIEUCHUNG - Lecture Address Space Management: Transitioning to IPv6
IPv6 offers many additional benefits to IPv4 including a larger address space, easier address aggregation, and integrated security. The IPv6 address is 128 bits long and is made up of a 48-bit global prefix, a 16-bit subnet ID, and a 64-bit interface identifier. There are several ways to assign IPv6 addresses: statically, stateless autoconfiguration, and DHCPv6. | Address Space Management Transitioning to IPv6 IPv4 and IPv6 Currently, there are approximately billion usable IPv4 addresses available. Lesson Aim Why Do We Need a Larger Address Space? Internet population Approximately 973 million users in November 2005 Emerging population and geopolitical address space Mobile users PDA, pen tablet, notepad, and so on Approximately 20 million in 2004 Mobile phones Already 1 billion mobile phones delivered by the industry Transportation 1 billion automobiles forecast for 2008 Internet access in planes, for example, Lufthansa Consumer devices Sony mandated that all its products be IPv6-enabled by 2005 Billions of home and industrial appliances IPv6 Advanced Features Larger address space: Global reachability and flexibility Aggregation Multihoming Autoconfiguration Plug-and-play End-to-end without NAT Renumbering Mobility and security: Mobile IP RFC-compliant IPsec mandatory (or native) for IPv6 Simpler header: Routing efficiency Performance and forwarding rate scalability No broadcasts No checksums Extension headers Flow labels Transition richness: Dual stack 6to4 and manual tunnels Translation IPv6 Address Representation Format: x:x:x:x:x:x:x:x, where x is a 16-bit hexadecimal field Case-insensitive for hexadecimal A, B, C, D, E, and F Leading zeros in a field are optional Successive fields of zeros can be represented as :: only once per address Examples: 2031:0000:130F:0000:0000:09C0:876A:130B Can be represented as 2031:0:130f::9c0:876a:130b Cannot be represented as 2031::130f::9c0:876a:130b FF01:0:0:0:0:0:0:1 FF01::1 0:0:0:0:0:0:0:1 ::1 0:0:0:0:0:0:0:0 :: IPv6 Address Types Unicast: Address is for a single interface IPv6 has several types (for example, global, reserved, link-local, and site-local) Multicast: One-to-many Enables more efficient use of the network Uses a larger address range Anycast: One-to-nearest (allocated from unicast address space) Multiple devices share the same address All .
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