27th September 2016 Yanick.Pouffary@Compaq.Com IPv6 27th September 2016 Yanick.Pouffary@Compaq.Com

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 Web, ftp, telnet, etc. application presentation session transport TCP, UDP network IPv4 link Ethernet physical

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 Web, ftp, telnet, etc. application presentation session transport TCP, UDP network IPv6 link Ethernet physical

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

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

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 Extensive infrastructure require for mobility

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)

… 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

IPv6 Base Technology Wins

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

IPv6 Header – Comparison with IPv4 bit bit 8 16 24 31 4 12 16 24 31 Version IHL Service Type Total Length Version Class Flow Label Identifier Flags Fragment Offset Payload Length Next Header Hop Limit Time to Live Protocol Header Checksum 32 bit Source Address 128 bit Source Address 32 bit Destination Address Options and Padding IPv4 Header 20 octets, 12 fields, including 3 flag bits + fixed max number of options 128 bit Destination Address Changed Removed IPv6 Header 40 octets, 8 fields + Unlimited Chained Extension (options) Header

IPv6 Extension Headers IP options have been moved to a set of optional Extension Headers Extension Headers are chained together IP options have been moved to a set of optional Extension Headers Extension Headers are chained together “Next Header” field indicated what follows next! “Next Header” field value maps the IPv4 Protocol field (where applicable) Ordering defined and must be processed in the order in which they appear Most need to be processed at destination Host Hop-by-Hop Options ** Jumbo Payload Routing ** Fragmentation Destination Options Mobile Binding Update Anycast Address Dynamic Update Authentication (RFC 2402) Encapsulating Security Payload (RFC 2406) No Next Header IPv6 Header Next = TCP TCP Header Application Data IPv6 Header Next = Frag TCP Header Fragment Hdr Next = Security Security Hdr Next = TCP Data Frag

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

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

Management Addressing Security The power of IPv6 Management Addressing Security

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 Multiple subnets on same link IPv6 addresses have scope and lifetime Link-Local Site-Local Global

IPv6 Unicast Address 3FFE:0301:DEC1:: 0A00:2BFF:FE36:701E 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 n bits 128-n bits prefix Interface ID Prefix Representation <prefix>::/<n-bits> 3FFE:0301:DEC1:: 0A00:2BFF:FE36:701E

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

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)

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

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)

Management Addressing Security The power of IPv6 Management Addressing Security

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”) 9

Summary

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

IPv6 key features and Advantages Available TODAY in commercial products 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

Conclusion Imagine what IPv6 can do for you! 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!

Questions?