IPV6

IPV6

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Do We Need IPv6?

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Why Do We Need IPv6? There Are Many Legitimate ReasonsSuch asWere running out of IPv4 addresses (this is the one reason which everyone always thinks of)

IPv6 may allow us to regain end-to-end transparency (widely overlooked but very important)

Long term, we need to contain route table bloat

IPv6 has been mandated in some environments (e.g.,theoretically for federal government networks)

Some Real Reasons for NOT Deploying IPv6Some sites may NOT be in any particular rush to deploy IPv6 becauseTheir site already has abundant IPv4 spaceAnything thats available via IPv6, is also available via IPv4 (at least for now)Their network uses middleboxes (such as firewalls or network load balancers) that are not fully IPv6 awareTheir network provider is still dragging their heels when it comes to providing IPv6 connectivity.

Bogus Reasons for NOT Deploying IPv6There are also many, many bogus reasons why some sites may NOT want to deploy IPv6, including:Im too busy working on more important things.This whole IPv4 exhaustion thing is a bunch of malarky folks will figure out some way to stretch out what space weve still got available.IPv6 and those super long addresses are just too weird/hard.Bottom line, customers (except you!) just arent asking for IPv6 support.

Whats wrong with IPv4 ?"address space exhaustion by 2005" !?-) billions of new devices, users-) 'always-on' technologiesdifficult (re-)configurationsophisticated, structured headerno integrated end-to-end security solutionNAT is no longer adequate-) no 'called' services (e.g. IP-phones)-) performance, security, mgmt. issues

What can IPv6 do better ?128 bit address 2128 = 3.4x1038 =340.282.366.920.938.463.463.374.607.431.768.211.456auto configuration / plug and playsimple header mandatory end-to-end security (IPsec)renumbering & multihomingmobility features

Addressing128 bit (64 for routing, 64 for interface ID)unicast, anycast, multicastaddresses have scope and lifetimeaddress autoconfiguration rulesmultiple addresses per interfaceeasy renumbering, reconfigurationhighly aggregatableinitially only 15% assigned by IANA

Routingsimplified header + extension headerpath MTU discovery in end systemssimple source routing facilities

Routing Protocol SupportIPV4 and IPv6 coexistence is easyin principle: no new routing architecture==> but no magical solution for multihomingrouting protocols must be able to support different "address families"both for IGPs (e.g. OSPFv3) and EGPs (e.g. BGP4+)more or less a simple extensio of existing concepts to e.g. support multicastNeeds a bit more memory