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camper
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Re: [Business] Any updates on the IPv6 business trials?

Yup. A sparsely-used address block is just as bad as a fully-used address block.

My biggest wonder is the reasoning behind the 64-bit subnet size. I have a server co-located in a data center. That server is allocated a /64 prefix. Based upon what I've found out, the /64 prefix seems to be the smallest allocation unit in IPv6 if you need a subnet. My single server needs, at most, 64 addresses, yet it was allocated 18,446,744,073,709,551,616 addresses. Sure, it is sometimes fun spelling out words in the addresses using the hex characters, but what a waste of addresses a /64 subnet is.

I'm not sure why the smallest allocation unit couldn't be something more reasonable, and something less likely to result in sparse address allocation within a block. Even if the subnet minimum were reduced to a /32, that would help, yet still allow billions and billions (channeling Carl Sagan) of addresses in the subnet.

DarkLogix
Texan and Proud
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join:2008-10-23
Baytown, TX

DarkLogix

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well its not the smallest and for a server that should only have statics I'd give it say a /121
you'd have to know how to VLSM though but you then wouldn't have a barren block.

its just SLAAC doesn't work if its not /64, but if its only going to have servers and you're going to use manually assigned vs slaac assigned then VLSM it yo the right size.

sure on my home net I'm going to keep slaac functional on all "access" vlans because if I connect a computer to it I want it to just work.

on my 2 "serialized" vlans when I re-do my IP layout I'll make them more closely match their ipv4 counter parts (IE VLSM'ed down to 2 usable)

camper
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Bethel, CT

camper

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I was playing around with subnets smaller than /64 on my home network and ran full tilt into the SLAAC limitation. SLAAC was not a happy camper with a /80 delegation.

btw, one reason I can think of for the /64 choice was that it may make routing easier and / or more efficient. {shrug}

DarkLogix
Texan and Proud
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Baytown, TX

DarkLogix

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ya if you want to do smaller than /64 then just forget about slaac.
though that means manual IP addressing

I could see how some might make some network hardware that would be geared to working with /64's

just break the IP into 2 64bit chunks, first is the network the second is the host portion, and while that is a way to leverage the commonness of /64 it would potentially limit the device to not working with smaller than /64 directly.

With each section (not sure of the name, IPv4 had octests) being 16bitsand 16 bits should really be all that a company needs to do site and vlan coding into the address it will be awhile before anything happens

personally I like the way of doing as 48:Site Code VlanID:64
then the site vlan ID part is from 0000 to FFFF with 00 to FF for each.

camper
just visiting this planet
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join:2010-03-21
Bethel, CT

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camper

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Just as IPv4 went from Class A, B, C, D networks to CIDR; I suspect IPv6, at some time in the future, may need to go to some other notation for subnets.

Maybe you should submit the RFC now, and get a jump on things.

NetDog
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join:2002-03-04
Hollywood, FL

NetDog to camper

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said by camper:

Yup. A sparsely-used address block is just as bad as a fully-used address block.

Can't agree more..
said by camper:

My biggest wonder is the reasoning behind the 64-bit subnet size.

The original architect's of IPv6 planned for MAC addresses to change to 64-bit. So SLAAC would not break if the MAC addresses changed to 64-bit.
said by DarkLogix:

well its not the smallest and for a server that should only have statics I'd give it say a /121

I would not do anything smaller then a /96, the math and subnetting areas get a little odd after that..
NetDog

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NetDog to camper

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to camper
said by camper:

 
Just as IPv4 went from Class A, B, C, D networks to CIDR; I suspect IPv6, at some time in the future, may need to go to some other notation for subnets.

Maybe you should submit the RFC now, and get a jump on things.

If anyone wants to write an RFC count me in... I think (not the opinion of my employer) the smallest subnet size should be /96. I don't say that anymore at IETF meetings, some people really feel strong about this subject..

DarkLogix
Texan and Proud
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Baytown, TX

DarkLogix to NetDog

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said by NetDog:

said by DarkLogix:

well its not the smallest and for a server that should only have statics I'd give it say a /121

I would not do anything smaller then a /96, the math and subnetting areas get a little odd after that..

Not really just gotta know how to convert to binary.

and IIRC ipv6 unlike ipv4 doesn't have a network and a broadcast address

NetDog
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join:2002-03-04
Hollywood, FL

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NetDog to camper

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to camper
said by camper:

 
Just as IPv4 went from Class A, B, C, D networks to CIDR; I suspect IPv6, at some time in the future, may need to go to some other notation for subnets.

Maybe you should submit the RFC now, and get a jump on things.

SLAAC would have to be fixed for this to work, but I see that in the future as well..

camper
just visiting this planet
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Bethel, CT

camper to NetDog

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said by NetDog:

... some people really feel strong about this subject..

 

Why do I get the impression that your comment is an example of understatement, as used in the English language?