1. IPv6 • Current version of the Internet Protocol is Version 4 (v4) • Earlier versions were not implemented • The next version will be Version 6 (v6) • No v5 was implemented • Informally called IPng (Next Generation) • IPv6 is Already Defined • Continuing improvements in v4 may delay its adoption

2. IPv6 • IPv6 will raise the size of the internet address from 32 bits to 128 bits • Now running out of IP addresses • Will solve the problem • But current work-arounds are delaying the need for IPv6 addresses

3. IPv6 • Improved Security • But, through IPsec, v4 is being upgraded in security as well • Improved Quality of Service (QoS) • But under IETF Differentiated Services (diffserv) initiative, IPv4 is being upgraded in this area as well

4. IPv6 • Extension Headers • IPv4 Headers are complex • IPv6 basic header is simple • Extension headers for options Basic Header Extension Header 1 Extension Header 2

5. IPv6 • Extension Headers • Basic header has 8-bit Next Header field • Identifies first extension header or says that payload follows Basic Header NH Extension Header 1 Extension Header 2

6. IPv6 • Extension Headers • Each extension header also has 8-bit Next Header field • Identifies next extension header or says that payload follows Basic Header Extension Header 1 NH Extension Header 2

7. IPv6 • Extension Headers • Next header field is an elegant way to allow options • Easy to add new extension headers for new needs Basic Header Extension Header 1 NH Extension Header 2