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Proposed IPv6 Cutover By 2011-01-01
IO ERROR writes "An internet-draft published this month calls for an IPv6 transition plan which would require all Internet-facing servers to have IPv6 connectivity on or before January 1, 2011. 'Engineer and author John Curran proposes that migration to IPv6 happen in three stages. The first stage, which would happen between now and the end of 2008, would be a preparatory stage in which organizations would start to run IPv6 servers, though these servers would not be considered by outside parties as production servers. The second stage, which would take place in 2009 and 2010, would require organizations to offer IPv6 for Internet-facing servers, which could be used as production servers by outside parties. Finally, in the third stage, starting in 2011, IPv6 must be in use by public-facing servers.' Then IPv4 can go away."
While IPv6 fixes many problems in IPv4, the developed world will not
embrace IPv6 until many shortcomings in the protocol are addressed.
1. Cisco routers suck at IPv6. Many of cisco's routers use the
router's CPU to process IPv6 packets instead of the fast-path. The
reasons for this are explained in the next few points. While Juniper's
routers are substantially better at IPv6 than cisco's, IT managers are
often restrained by insane corporate policy that dictactes the use of
cisco.
2. There are too many addresses. There are 16.7 million addresses per
square metre of the earth's surface, including the oceans. This is
overkill. The world does not need more than the 4 billion addresses
available with IPv4, and I challenge you to come up with an
application that requires that many. Assuming that you can actually
come up with one, it could easily be solved with Network Address
Translation, or NAT as it is commonly known.
3. IPv6 addresses are too large. An IPv6 address is 128 bits in size -
64 bits of which are reserved for addressing hosts, and 64 bits of
which are reserved for routing. One thing that is cool with IPv6 is
address autoconfiguration. Take your 56-bit MAC address on your
ethernet card, ask for 64-bits of network prefix, bang it together
with EUI-64 and you are set. The problem with a 64-bit network prefix
is that routing tables become massive. Just do the math and you'll see
that extreme amounts of memory are required to hold routing tables.
4. The IPv6 header is too large. An IPv4 header compact at 20 bytes in
length, while the IPv6 is bloated at 40 bytes. That's right niggers,
each one of your IP packets has twice as much overhead as before.
While this may not sound much, IP networks have a requirement that the
minimum MTU supported must be 576 bytes. That means that where you
might have got 556 bytes of data in your IP packets, you now get 536
bytes. This means that downloading stuff will take 3.4% longer.
Sure, IPv6 allows for nice hacks like those described in this article,
but is it really ready for prime time?