1. 1 IPv6 Advantages May 2001 Yanick.Pouffary@Compaq.Com May 2001 Yanick.Pouffary@Compaq.Com

2. 2 What is IPv4?  Version 4 of the Internet Protocol  30+ Years Old  Incredibly successful –Today’s Internet runs over IPv4  IPv4 address is 32 bits  Many add-ons  Showing its age presentation session application transport network link physical IPv4 TCP, UDP Ethernet Web, ftp, telnet, etc.

3. 3 What is IPv6?  Version 6 of the Internet Protocol –Version 5 was allocated to the experimental Internet Stream Protocol (RFC 1190)  5+ years old  Poised for the continued growth and success of the Internet  IPv6 address is 128 bits presentation session application transport network link physical IPv6 TCP, UDP Ethernet Web, ftp, telnet, etc.

4. 4 IPv4: A Victim of Its Own Success  1990 - IPv4 addresses being consumed at an alarming rate, projections show:  Class B address space exhausted by 1994  All IPv4 address space exhausted between 2005 - 2011 –Internet routing tables suffering explosive growth  Internet routing today is inefficient  Running out of Internet addresses –Stops Internet growth for existing users –Prevents use of the Internet for new users –Forces users to use Private Addresses

5. 5 Interim Measures  CIDR (Classless Inter-Domain Routing) –Eased routing table growth  Private addresses –Reduced pressure on address space, but… –Necessitated Network Address Translation, but…  Single point of failure  Network performance penalty  Breaks applications that rely on end-to-end IP addressing (FTP, DNS, others) –Use ALGs

6. 6 More User Problems with IP today  System administration –Labor intensive, complex, slow, and error prone –Subscriber networks cannot be dynamically renumbered or configured  Security is optional; no single standard  No support for new protocols –Difficult to add to the base IPv4 technology

7. 7 Interim Measures Helped, But …  Address space consumption slowed, but Internet growth accelerated –“Everything to the Internet”  1B mobile users by 2005  1B Internet users by 2005  90% of all new mobile phones will have internet access by 2003 (Morgan Stanley Dean Witter, May 2000)  Projections of address space exhaustion by 2010 –Pain Sooner (Europe and Asia)

8. 8 … a longer term solution IP next generation (IPng)  1991: Work starts on next generation Internet protocols –More than 6 different proposals were developed  1993: IETF forms IPng Directorate –To select the new protocol by consensus  1995: IPv6 selected –Evolutionary (not revolutionary) step from IPv4  1996: 6Bone started  1998: IPv6 standardized  Today: Initial products and deployments

9. 9 IPv6 Base Technology Wins

10. 10 Design Philosophy  Recognizable yet simplified header format  Reduce common-case processing cost of packet handling  Keep bandwidth overhead low in spite of increased size of the address  Flexible and extensible support for option headers  Design optimised for 64-bit architecture –Headers are 64-bit aligned

11. 11 128 bit Source Address 128 bit Destination Address bit 0 31 Version IHLTotal Length IdentifierFlagsFragment Offset 32 bit Source Address 32 bit Destination Address 82416 Service Type Options and Padding Time to LiveHeader ChecksumProtocol 31 Version ClassFlow Label Payload Length Next Header Hop Limit 4122416 IPv6 Header – Comparison with IPv4 IPv4 Header 20 octets, 12 fields, including 3 flag bits + fixed max number of options IPv4 Header 20 octets, 12 fields, including 3 flag bits + fixed max number of options IPv6 Header 40 octets, 8 fields + Unlimited Chained Extension (options) Header IPv6 Header 40 octets, 8 fields + Unlimited Chained Extension (options) Header Removed Changed bit 0

12. 12 IPv6 Header Next = TCP TCP HeaderApplication DataIPv6 Header Next = Frag TCP HeaderFragment Hdr Next = Security Security Hdr Next = TCP Data Frag IPv6 Extension Headers  IP options have been moved to a set of optional Extension Headers  Extension Headers are chained together

13. 13 IPv6 Header Performance Wins Layout  Fixed Size IPv6 Header –Unlike IPv4 - Options not limited at 40 bytes  Fewer fields in basic header –faster processing of basic packets  64 Bit Alignment Header/Options  Efficient option processing –Option fields processed only when present –Processing of most options limited performed only at destination

14. 14 IPv6 Header Performance Wins Processing IPv6 Header Performance Wins Processing  Remove checksum from Network Layer –Datalinks are more reliable these days –Upper Layer checksums are now mandatory (for example, TCP, UDP, ICMPv6)  No fragmentation in the network –Reduce load on routers –Easier to implement in hardware –Easy for Layer 3 switching of IP  Minimum link MTU is 1280 bytes –From 68 in IPv4

15. 15 The power of IPv6 Addressing Management Security Addressing Management Security

16. 16 Addressing Model (RFC 2373)  Addresses assigned to interfaces  No change from IPv4 model  Interfaces typically have multiple addresses  Subnets associated with single link  A link is a link-layer (layer 2) domain e.g. LAN  No change from IPv4 model  Multiple subnets on same link  IPv6 addresses have scope and lifetime Link-Local Site-LocalGlobal

17. 17 IPv6 Unicast Address  Address = prefix of n bits + interface ID of 128-n bits  Separate “who you are” from “where you are connected to”  Aggregatable Global Unicast Address format prefixInterface ID 128-n bits n bits Prefix Representation ::/ 3FFE:0301:DEC1::0A00:2BFF:FE36:701E

18. 18 The power of IPv6 Addressing Management Security Other IPv6 goodies Addressing Management Security Other IPv6 goodies

19. 19 Network Management  Address Autoconfiguration –Designed for hosts  It is assumed that routers are configured by some other means –Provides “Plug-and-Play” capability –Defines methods for obtaining routable address(es):  Link Local Address (No router or server required)  Stateless mechanism (Router advertisements provide prefix)  Stateful mechanism (Server provides address ( DHCP)

20. 20 Network Management  Renumbering IPv6 hosts is easy –Add a new prefix to the router –Reduce the lifetime of the old prefix –As nodes deprecate the old prefix, they begin using the new prefix for new connections –No network downtime  Renumbering IPv6 routers –New protocol: Router Renumbering (RFC 2894)  An end of ISP “lock in”! –Improved competition

21. 21 Mobile IPv6  IPv6 Mobility is based on core features of IPv6 –The base IPv6 was designed to support Mobility –Mobility is not an “Add-on” features  IPv6 Neighbor Discovery and Address Autoconfiguration allow hosts to operate in any location without any special support  No single point of failure (Home Agent)  More Scalable : Better Performance –Less traffic through Home Link –Less redirection / re-routing (Traffic Optimisation)

22. 22 The power of IPv6 Addressing Management Security Addressing Management Security

23. 23 IPv6 Mandates IP Security  Security features are standardized and mandated –All implementations must offer them  Extensions to the IP protocol suite (RFC 2401) –Authentication (Packet signing) –Encryption (Data Confidentiality)  Operates at the IP layer –Invisible to applications  Protects all upper layer protocols  Protects both end-to-end and router-to-router (“secure gateway”)

24. 24 Summary

25. A decade of design and testing Core IETF specs have reached Draft Standard status Interne t Draft RFC Proposed Standard RFC Draft Standard RFC Internet Standard Technically complete Multiple Interoperable Implementations Significant Operational Experience Yes No timeline 1991 Today 6bone test bed 1996 1998

26. 26 IPv6 key features and Advantages  Increased Address Space  Efficient and extensible IP datagram  Improved host and router discovery  Plug and Play  Enhancements for Quality of Service (QoS)  Improved Mobile IP support  IPsec mandated  Coexistence with IPv4  Extensibility of the Architecture Available TODAY in commercial products

27. 27 ConclusionConclusion  IPv6 Solves many of the problems caused by the IPv4 success and more...  The technology you’ve been waiting for is here… Start deploying today! Imagine what IPv6 can do for you!

28. 28 Questions?Questions?