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Christophe Jelger Post-doctoral researcher Christophe.Jelger@unibas.ch

The Internet Protocol version 6 (IPv6) : Evolution or Revolution ?. Christophe Jelger Post-doctoral researcher Christophe.Jelger@unibas.ch. Plan. Motivations behind IPv6 IP is History … Lack of IPv4 addresses ? Growth of routing tables Unfairness in IPv4 address allocation

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Christophe Jelger Post-doctoral researcher Christophe.Jelger@unibas.ch

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  1. The Internet Protocolversion 6 (IPv6) :Evolution or Revolution ? Christophe Jelger Post-doctoral researcher Christophe.Jelger@unibas.ch Christophe Jelger – CS221 Network and Security - Universität Basel - 2005

  2. Plan • Motivations behind IPv6 • IP is History … • Lack of IPv4 addresses ? • Growth of routing tables • Unfairness in IPv4 address allocation • Required features of IPng • So what's new in IPv6 ? • Address format and scoped addresses • IPv6 header vs. IPv4 header • New features : autoconfiguration, improved mobility support Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  3. Plan • Address allocation with IPv6 • Hierarchical routing everywhere • Today's IPv6 world • Where are we today ? • Current status of IPv6 • From IPv4 to IPv6 Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  4. Motivationsbehind IPv6 When the main issues are not related to end users Where are We today ? Motivations Behind IPv6 So what's New in IPv6 ? Address Allocation With IPv6 Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  5. IP is History … and the Internet is growing • The current version (4) of the IP protocol is 30 years old • IP is everywhere : it has become the de facto standard • The Internet is growing … • 1973 : research network (~100 machines) • Mid-80s : early adoption and first address allocations • 1992 : First commercial applications and start of the Web • 1993 : first address crisis – CIDR introduced • no more addresses by 1994 ! • Exponential growth • 2002 : 600 million Internet users Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  6. Lack of IPv4 addresses ? • A very hot topic … • Address exhaustion was predicted many times • Current estimates : 5 to 20 years to go • 2011-2012: IANA unallocated address space is assigned • 2026: exhaustion of the RIRs' address spaces • Drawback is that getting addresses becomes very difficult • Address allocation is strongly unfair • IPv4 • Address length is 32 bits : theoretically, that is 4.5 billion addresses • But addressing is not so simple … • Allocation is network-based Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  7. Lack of IPv4 addresses ? • Class-based address architecture Network id Host id 32 bits Class A network 127 networks each with 16,777,216 hosts 8 bits 24 bits Class B network 16,128 networks each with 65,536 hosts 16 bits 16 bits Class C network 2,031,616 networks each with 256 hosts 24 bits 8 bits 1993 : no Class B networks available ! Class-less Inter-Domain Routing (CIDR) introduced Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  8. Lack of IPv4 addresses ? • CIDR • Allows network-id of any length (e.g. /13, /26) • E.g. /18 = 16384 hosts and /19 = 8192 hosts • Aggregation and hierarchical routing • An ISP get a /15 address space and it redistributes sub-parts of it, e.g. 512 /24 networks • Routing to all the ISP's clients is done via the /15 • Also adddress allocation became more strict Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  9. Lack of IPv4 addresses ? • CIDR solved the problem … until when ? • Around 65 /8 are still available (78 in November 2004) • At the current pace, 5 /8 (100M addresses !) are used every year, but this rate is growing as emerging countries are hungry in addresses (China, India, African countries) • Address allocation is becoming a nightmare • We must move ahead before it's too late • Still a big waste of address space • UniBasel : 8500 active machines but a /16 network (65,536 hosts) • Non-ISP entities still have a /8 address space (IBM, HP, Xerox, Apple, MIT, Ford, Lily, Halliburton) • BUT the problem is not only the lack of addresses … Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  10. Growth of routing tables • In the core part of the Internet, routers do not have a default route : this is the Default-Free Zone (DFZ) • In 2000, the size of routing tables in the DFZ is around 75,000 entries • In 2001, it is around 100,000 • In December 2004, this value is between 150,000 and 180,000 • In April 2007, this value reaches 300,000 for some ASs ! • Routing updates are getting slower • Operational maintenance becomes more and more complex Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  11. Growth of routing tables • Main cause : aggregation is not sufficient • The top 30 operators could reduce their announcements by 68.6% with proper aggregation (67% in 2006, 60% in 2005) • The DFZ size could be reduced by 50.7% with aggregation for all ASs (34% in 2006, 30% in 2005) • Aggregation alone cannot significantly reduce the size of the DFZ: A complete address re-allocation should be made • 131.152.0.0/16 UniBasel – 131.153.0.0/16 Sematech, TX • THIS IS IMPOSSIBLE ! • Except if a new addressing scheme is used : IPv6 ! Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  12. Unfairness in address allocation • Historically, addresses have been assigned on a first-come first-serve basis • But today, addresses are assigned in a very strict way • Some countries fail to obtain sufficient addresses • When others have far too many addresses • United States : 4.2 addresses / inhabitant (9.4 per Internet user) • Switzerland : 1.4 addresses / inhabitant (4 per Internet user) • France : 0.6 addresses / inhabitant (3.4 per Internet user) • China : 0.02 addresses / inhabitant (0.54 per Internet user) • India : 0.003 addresses / inhabitant (0.38 per Internet user) • Senegal : 8.192 addresses (10M inhabitants) • Mali : 4.096 addresses (13 M inhabitants) • Congo : 0 addresses (52 M inhabitants) Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  13. Required features of IPng (next generation) • RFC-1380 : from IESG (Internet Engineering Steering Group) • IPng must be capable of addressing 1012 networks • Transition to IPng must be done without the need of a D-day • IPng must be easily extended with new features • Deployment features • Hierchical routing MUST be the norm • Getting an address space must be straightforward • Autoconfiguration Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  14. So what's new in IPv6 ? Myths and reality … Where are We today ? Motivations Behind IPv6 So what's New in IPv6 ? Address Allocation With IPv6 Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  15. Address format and scoped addresses (RFC 3513) • 128 bits (16 octets) • That is potentially 3.4 x 1038 addresses • And 1.8 x 1019 /64 networks ! • 64-64 is the norm : a /64 network can accommodate any number of devices ! • Notation • IPv4 : 131.152.230.33/16 • IPv6 : 2001:620:200:1:200:e2ff:fe9c:2282/64 • 2001:620:200:1:0:0:0:1  2001:620:200:1::1 • New DNS record : AAAA (A for IPv4) Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  16. Address format and scoped addresses • Scoped addresses • Link-local addresses : prefix fe80::/64 • Site-local (deprecated) : prefix fec0::/64 • Unique local (address scope is global but routing is restricted to a site) : prefix fc00::/7 (but /64 when deployed) • Multicast : ff00::/8 • Link-scope : ff02::/16 • Site-scope : ff05::/16 • Global-scope : ff0e::/16 • Well-known addresses : no layer-3 broadcast any more • ff02::1 all nodes on link, ff02::2 all routers on link • ff02::16 all MLDv2 multicast routers • Special addresses • Loopback : 0:0:0:0:0:0:0:1 or ::1 • Unspecified : 0:0:0:0:0:0:0:0 or :: Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  17. IPv6 header vs. IPv4 header (RFC 2460) 20 bytes (without option) 40 bytes Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  18. IPv6 header vs. IPv4 header • Header format is simplified • Optional headers are daisy-chained • No checksum at IP layer (it's done by other layers) • No re-computation by each router • No hop-by-hop segmentation • Path MTU discovery • 64 bits aligned • ARP (address Resolution Protocol) is replaced by Neighbor Discovery at the ICMP6 layer Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  19. IPv6 header vs. IPv4 header • Optional headers • Hop-by-Hop header: information that must be processed by all intermediate hops • Used by ICMP6 (MLD, Multicast Listener Discovery) • Routing header: the source node can specify one or multiple intermediate hops via which the packet must travel (source-routing) • Used by Mobile IPv6 • Fragment header: to send a packet which has a size > MTU • Destination option: to carry additional information that must be processed by the destination • Used by Mobile IPv6 Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  20. New features • Stateless Address Autoconfiguration (RFC 2462) MAC : 00:07:85:92:7F:F8 IPv6 router Prefix + EUI-64 (+universal bit) IPv6 prefix 2001:660:4701:f002:207:85ff:fe92:7ff8/64 2001:660:4701:f002::/64 also internally done for fe80::207:85ff:fe92:7ff8/64 Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  21. New features: ICMPv6 • Neighbor Discovery (RFC 2461) • Main feature is the replacement of ARP IPv6: fe80::207:85ff:fe92:7ff8/64 MAC : 00:07:85:92:7F:F8 + 33:33:ff:92:7f:f8 IPv6: fe80::20b:5dff:fe58:9eec/64 MAC : 00:0B:5D:58:9E:EC Neighbor sollicitation Neighbor advertisement Eth dst addr: 33:33:ff:92:7f:f8 (multicast MAC address) IPv6 dst addr: ff02::1:ff92:7ff8 (sollicited multicast address) Target: fe80::207:85ff:fe92:7ff8 Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  22. New features • Stateless Address Autoconfiguration • Duplicate Address Detection (DAD) • Security issues and DNS dynamic updates are currently being investigated by IETF. • Who's behind which machine ? (URZ) • Improved support for • Mobility (Mobile IPv6) • Security (IPSec) is integrated • Multicast deployment through RP-embedded addresses • Myths : IPv6 does NOT provide • Any QoS features • Any kind of improved performance Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  23. Address Allocationwith IPv6 Where the BIG difference is … Where are We today ? Motivations Behind IPv6 So what's New in IPv6 ? Address Allocation With IPv6 Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  24. AGUA (Aggregatable Global Unicast Addresses) Provider Site Host 45 bits 16 bits 64 bits 3 bits 001 Global Routing Prefix SLA Host ID • Current allocation scheme • IANA has decided to start with 2001::/16 • IANA allocates /23 to registries • RIPE (Europe) : 2001:600::/23 • ARIN (North America) : 2001:400::/23 • APNIC (Asia) : 2001:200::/23 • Registries allocate /32 to ISP • SWITCH : 2001:620::/32 • RENATER : 2001:660::/32 Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  25. Allocation Scheme • ISP allocate /48 or /64 to customers • UniBasel : 2001:620:200::/48 • UniStrasbourg : 2001:660:4701::/48 • /64s are for end users (via ADSL or cable) • Hierarchical routing IS the norm • With IPv4, SWITCH announces 88 prefixes (could be reduced to 87) which CANNOT be aggregated ! • With IPv6, SWITCH announces one prefix ! (2001:620::/32) • Current DFZ size is around 850 (300,000 for IPv4!) • Proper aggregation could reduce this by 4%. • Max DFZ until re-allocation is 4096 Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  26. Today's IPv6 world • Only 0.0008 % of the entire IPv6 address space is used ! (i.e. the equivalent of about 152,000 billion /64 networks ! • In 2006: 0.0007% and 130,000 billion /64s • In 2005: 0.0005% and 90,000 billion /64s) • IPv6 ready-networks : WIDE, Geant (european academic network), Internet2 (US academic network), AOL, Swisscom, NASA, FT, BT etc … • Deployment in end-sites is slow • IPv6 is not a revolution : not much added value for end-users • Developed countries have plenty of IPv4 addresses • Still, IPv6 will eventually replace IPv4 : it's a matter of time ! Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  27. Where are we today ? Status of IPv6 specifications Where are We today ? Motivations Behind IPv6 So what's New in IPv6 ? Address Allocation With IPv6 Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  28. IPv6 status • Most part of the protocol is specified and has proved to work well (around 10 years of experimentation) • Areas that are currently considered • Default router selection and specific routes (multi-homing) • Load sharing • Privacy extensions for address autoconfiguration • Secure DNS update and secure autoconfiguration • Most systems are IPv6-ready • *BSD, Linux, Windows 2000 and XP • Cisco, Juniper, and 6Wind routers • Most applications are also IPv6-ready Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  29. From IPv4 to IPv6 • Transition is difficult • End-users and end-sites do not feel concerned • There is no killer application for IPv6 • Many transitioning tools available • Dual-stack • Tunneling techniques : 6to4, ISATAP • Translation tools : NAT-PT, DSTM • Sooner or later IPv6 will prevail • In networks with IPv4 addresses : dual-stack is best • In native IPv6 networks, tunneling or translation is needed to reach IPv4 world Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

  30. Thank you Questions ? Christophe Jelger – CS221 Network and Security - Universität Basel - 2007

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