（精）国立清华大学资讯系黄能富教授.ppt

大綱 IPv6 Introduction Routing and Addressing Plug and Play Security/QoS Supports IPv4/Ipv6 Transition Mechanisms IPv6 Current Status IPv6 Applications Home Appliance Controllers VoIP/Video Streaming Remote Controllers 3G/4G Games Home Automation Others IP位址需求無所不在 The Design of IPv6 The Internet could not have been so successful in the past years if IPv4 had contained any major flaw. IPv4 was a very good design, and IPv6 should indeed keep most of its characteristics. It could have been sufficient to simply increase the size of addresses and to keep everything else unchanged. However, 10 years of experience brought lessons. IPv6 is built on this additional knowledge. It is not a simple derivation of IPv4, but a definitive improvement. IPv6Header Format A Comparison of Two Headers Six fields were suppressed: Header Length, Type of Service, Identification, Flags, Fragment Offset, Header Checksum. Three fields were renamed: Length, Protocol Type, Time to Live The option mechanism was entirely revised. Source Routing Route Recording Two new fields were added: Priority and Flow Label (to handle the real-time traffic). A Comparison of Two Headers Three major simplifications Assign a fixed format to all headers (40 bytes) Remove the header checksum Remove the hop-by-hop segmentation procedure From Options to Extension Headers Hop-by-Hop options header Routing header Fragment header Authentication header Encrypted security payload Destination options header Routing Header Fragment Header IPv6 Addressing Three categories of IPv6 addresses: Unicast Multicast Anycast Notation of IPv6 Addresses: Write 128 bits as eight 16-bit integers separated by colons Example: FEDC:BA98:7654:3210:FEDC:BA98:7654:3210 A set of consecutive null 16-bit numbers can be replaced by two colons Example: 1080:0:0:0:8:800:200C:417A = 1080::8:800:200C:417A Addressing Some Addresses formats Provider Addresses Link Local Addresses Site Local Addresses Multicast Addr