1 © 2001, Cisco Systems, Inc. All rights reserved. IPv6: Addressing the Future Fred Baker Cisco Fellow

© 2001, Cisco Systems, Inc. All rights reserved Points to ponder The past: where networks came from The future: where networks are going IPv6 innovations: what is really different? IPv6 debate: is IPv6 really a sufficient solution? IPv6 today: status in implementation and deployment

3 © 2001, Cisco Systems, Inc. All rights reserved. The Past

© 2001, Cisco Systems, Inc. All rights reserved Before IP Diverse networks joined by application-layer gateways Inevitable loss of functionality crossing proprietary application and network boundaries Difficult to deploy multi-network applications Hard to diagnose and remedy problems Stateful gateways inhibited dynamic routing around failures No global addressability Ad-hoc, application-specific solutions

© 2001, Cisco Systems, Inc. All rights reserved Fundamental Premises: Simple Applications, Smart Network Able to provide high quality services to specific applications Network does one thing well: deliver specified services to specified applications Intolerant of change Simple Network, Smart Applications End to End Principle Network does one thing well: ship packets Applications can do anything that can use that paradigm

© 2001, Cisco Systems, Inc. All rights reserved The IP Solution IP routers & global addresses Simple, application-independent, least-common-denominator network service: best-effort datagrams Stateless gateways could easily route around failures With application-specific knowledge out of the gateways: Anyone could deploy new, internet- wide applications and services Internet became a platform for rapid, competitive innovation

© 2001, Cisco Systems, Inc. All rights reserved The Internet Today Network address translators and application-layer gateways Inevitable loss of some functions Difficult to deploy new internet- wide applications Hard to diagnose and remedy problems Stateful gateways inhibit dynamic routing around failures No global addressability Ad-hoc, application-specific (or ignorant!) Solutions

8 © 2001, Cisco Systems, Inc. All rights reserved. The Future

© 2001, Cisco Systems, Inc. All rights reserved The Probable Future Billions and billions of new Internet devices Billions of new Internet users Internet available everywhere, all the time (wired, wireless, mobile,…) Convergence of all communication on the Internet (business, personal, entertainment, public services,…)

© 2001, Cisco Systems, Inc. All rights reserved. 10 © 2001, Cisco Systems, Inc. All rights reserved. 10 © 2001, Cisco Systems, Inc. All rights reserved. 10 The Unknown Future Continued degradation of the end to end model with IPv4? More complex and volatile network service => Lower performance, less robust, less secure, less manageable More centralized control over new applications and services => Significant barrier to innovation and growth

© 2001, Cisco Systems, Inc. All rights reserved. 11 © 2001, Cisco Systems, Inc. All rights reserved. 11 © 2001, Cisco Systems, Inc. All rights reserved. 11 The Unknown Future …or restoration of the end to end model with IPv6? Simple, stable network service => Higher performance, more robust, more secure, more manageable Enabling anyone to provide new applications and services => Allowing rapid innovation and growth

12 © 2001, Cisco Systems, Inc. All rights reserved. IPv6 Innovations

© 2001, Cisco Systems, Inc. All rights reserved. 13 © 2001, Cisco Systems, Inc. All rights reserved. 13 © 2001, Cisco Systems, Inc. All rights reserved. 13 Lots of Addresses IPv4 Internet: O(2 32 ) = 4,294,967,296 addresses Arbitrary division into networks 12.5% allocated to non-host addresses ~45% allocated to various networks ~26% advertised in today’s Internet Conservatively allocated IPv6 Internet: O(2 128 ) = 3.4*10 38 addresses O(2 64 ) = 18,446,744,073,709,551,616 Networks O(2 64 ) = 18,446,744,073,709,551,616 hosts per network Host addresses self-allocated Enough!

© 2001, Cisco Systems, Inc. All rights reserved. 14 © 2001, Cisco Systems, Inc. All rights reserved. 14 © 2001, Cisco Systems, Inc. All rights reserved. 14 Plug-and-play One of the nice things about AppleTalk: You can plug the device or computer in, and it just works One of the not-so-nice things about IPv4: You can plug the device or computer in… Configuring, and reconfiguring, can be hard DHCP helps a lot, but it requires properly configured servers IPv6 allows for Significant level of autoconfiguration Automated network renumbering Arbitrary device addressing within topological limits

© 2001, Cisco Systems, Inc. All rights reserved. 15 © 2001, Cisco Systems, Inc. All rights reserved. 15 © 2001, Cisco Systems, Inc. All rights reserved. 15 Mobility IPv4 Mobility Permits device to move using same home address All communication through Home Agent Foreign Agent must be a router IPv6 Mobility Permits device to move using same home address Communication via care-of address No Foreign Agent required Security Issues: Session hijack Duration of Switchover Dogleg Routing Optimized Routing

© 2001, Cisco Systems, Inc. All rights reserved. 16 © 2001, Cisco Systems, Inc. All rights reserved. 16 © 2001, Cisco Systems, Inc. All rights reserved. 16 Anycast Addressing and Naming of Applications One of the nice things about NetWare: Service Location Today: DNS lists several addresses for a name, but no information to help select a server

© 2001, Cisco Systems, Inc. All rights reserved. 17 © 2001, Cisco Systems, Inc. All rights reserved. 17 © 2001, Cisco Systems, Inc. All rights reserved. 17 Anycast Proposal: DNS lists one address, Servers are “routers” to that address DNS for service name, Common address for service location Topological address for specific access Issues: Route changes can change which server you use in mid-transaction Solution: Treat server as a mobile device which is currently stationary Connect to “home address” to select server, Thereafter talk to fixed “care-of address”

© 2001, Cisco Systems, Inc. All rights reserved. 18 © 2001, Cisco Systems, Inc. All rights reserved. 18 © 2001, Cisco Systems, Inc. All rights reserved. 18 Security issues IPv6 enables end-to-end use of IPsec protocols (because it eliminates NATs), Plus for security, although IPsec also exists in IPv4 Internet and is widely used for VPNs Authentication (“you are the person who knows this key”) Antidote to session hijack (“you are the same person I was just talking with”) Privacy (encryption, using symmetric or public key technology) IPsec authentication dependant on key distribution infrastructure, which is not currently a solved problem Affects mobility, anycast, secure communication in general

19 © 2001, Cisco Systems, Inc. All rights reserved. IPv6 Debate Geoff Huston’s questions

© 2001, Cisco Systems, Inc. All rights reserved. 20 © 2001, Cisco Systems, Inc. All rights reserved. 20 © 2001, Cisco Systems, Inc. All rights reserved. 20 Are we really running out of addresses? Growth in IPv4 advertisement rate not high But folks who need addresses can’t get them Largely a question of perspective If you already have your addresses assigned, getting them is not a worry

© 2001, Cisco Systems, Inc. All rights reserved. 21 © 2001, Cisco Systems, Inc. All rights reserved. 21 © 2001, Cisco Systems, Inc. All rights reserved. 21 Everyone doesn’t want a permanent address Everyone who wants one is not able to get one Example: People’s Republic of China 1.3 Billion people Order of magnitude growth in Internet usage year over year ~9M addresses in 1999 ~16M addresses in 2001 Do we simply assume that anyone who has not already asked never will? Africa, South America, India, Arab world…

© 2001, Cisco Systems, Inc. All rights reserved. 22 © 2001, Cisco Systems, Inc. All rights reserved. 22 © 2001, Cisco Systems, Inc. All rights reserved. 22 Every device is not a server In client/server applications Clients vastly outnumber servers Clients can be addressed on demand Examples: WWW, FTP, X-Windows But every application is not client/server Peer/peer applications Peer must be accessible and addressed when someone decides to talk with it Do we want to limit ourselves to the client/server model?

© 2001, Cisco Systems, Inc. All rights reserved. 23 © 2001, Cisco Systems, Inc. All rights reserved. 23 © 2001, Cisco Systems, Inc. All rights reserved. 23 Privacy? Privacy issues Concern: inclusion of MAC address in IPv6 breaks privacy Reality: 1:1 correlation between IP and MAC Address breaks privacy in either IPv4 or IPv6 Privacy solutions in IPv6 Autoconfiguration procedures enable, for example Random address changes every hour Address per user of multi-user machine Address per TCP session or per web page loaded

© 2001, Cisco Systems, Inc. All rights reserved. 24 © 2001, Cisco Systems, Inc. All rights reserved. 24 © 2001, Cisco Systems, Inc. All rights reserved. 24 Number of usable addresses Argument: IPv4+port gives 2 48 effective addresses IPv6 allocation gives 2 48 networks, 2 16 subnets, and a few hosts in each subnetwork Comparable when viewed on the service provider network Not really comparable Math error: 2 48  Not responsive to user network design issues

© 2001, Cisco Systems, Inc. All rights reserved. 25 © 2001, Cisco Systems, Inc. All rights reserved. 25 © 2001, Cisco Systems, Inc. All rights reserved. 25 Is it enough better to justify changing? Argument: IPv6 doesn’t change routing, trust model, QoS, etc It gives us IPv4 Internet with more addresses What IPv6 does do: Removes address conservation as an issue Enables kinds of applications current addressing makes difficult Simplifies deployment of new applications Eliminates need to kludge around addressing issues

26 © 2001, Cisco Systems, Inc. All rights reserved. IPv6 Today

© 2001, Cisco Systems, Inc. All rights reserved. 27 © 2001, Cisco Systems, Inc. All rights reserved. 27 © 2001, Cisco Systems, Inc. All rights reserved. 27 Standards Core IPv6 specifications are IETF Draft Standards => well-tested & stable IPv6 base spec, ICMPv6, Neighbor Discovery, PMTU Discovery, IPv6-over-Ethernet, IPv6-over-PPP,... Other important specs are further behind on the standards track, but in good shape Mobile IPv6, header compression, A6 DNS support,... For up-to-date status: UMTS R5 cellular wireless standards mandate IPv6

© 2001, Cisco Systems, Inc. All rights reserved. 28 © 2001, Cisco Systems, Inc. All rights reserved. 28 © 2001, Cisco Systems, Inc. All rights reserved. 28 Implementations Most IP stack vendors have an implementation at some stage of completeness Some are shipping supported product today, e.g., Cisco, 3Com, *BSD(KAME), Epilogue, Ericsson/Telebit, IBM, Linux community, Hitachi, Nortel, Sun, Trumpet Others have beta releases now, supported products soon, e.g., Compaq, HP, Microsoft Others rumored to be implementing, but status unknown e.g., Apple, Bull, Juniper, Mentat, Novell, SGI (see for most recent status reports) Good attendance at frequent testing events

© 2001, Cisco Systems, Inc. All rights reserved. 29 © 2001, Cisco Systems, Inc. All rights reserved. 29 © 2001, Cisco Systems, Inc. All rights reserved. 29 Deployment Experimental infrastructure: the 6bone for testing and debugging IPv6 protocols and operations (see Production infrastructure in support of education and research: the 6ren CAIRN, Canarie, CERNET, Chunahwa Telecom, Dante, ESnet, Internet 2, IPFNET, NTT, Renater, Singren, Sprint, SURFnet, vBNS, WIDE (see Commercial infrastructure Some ISPs (IIJ, NTT, SURFnet, Trumpet,…) have announced commercial IPv6 service or service trials Japan and China have announced national direction

© 2001, Cisco Systems, Inc. All rights reserved. 30 © 2001, Cisco Systems, Inc. All rights reserved. 30 © 2001, Cisco Systems, Inc. All rights reserved. 30 Deployment (cont.) IPv6 address allocation 6bone procedure for test address space Regional IP address registries (APNIC, ARIN, RIPE- NCC) for production address space Deployment advocacy (a.k.a. marketing) IPv6 Forum:

© 2001, Cisco Systems, Inc. All rights reserved. 31 © 2001, Cisco Systems, Inc. All rights reserved. 31 © 2001, Cisco Systems, Inc. All rights reserved. 31 IPv6 Advanced Features Plug-and-play We have most of the pieces for IP and DNS layers; still need work on auto-configuration of applications and services Mobility To get most efficient routing in all cases, need to deploy solid security Security IPv6 enables end-to-end use of IPsec protocols (because it eliminates NATs), Also dependant on key distribution infrastructure, which is absent Quality of Service IPv6 QoS features are same as IPv4’s, but less widely implemented

© 2001, Cisco Systems, Inc. All rights reserved. 32 © 2001, Cisco Systems, Inc. All rights reserved. 32 © 2001, Cisco Systems, Inc. All rights reserved. 32 Conclusions IPv6 is addressing the future… Addresses for new devices, new applications, and new users Restoring the end to end model, for performance, robustness, security, manageability, and enabling rapid innovation Enhancing IP for next-generation applications: multicast, mobility, plug-and-play, security, and multiple qualities of service …but is it a future we will see? Must apply much more energy, in design, implementation, deployment, transition, training, explaining,… The only way to fight entropy is to apply energy