[6lo] IID length in draft-ietf-6lo-btle-06.txt - why64?
Alexandre Petrescu <alexandre.petrescu@gmail.com> Fri, 16 January 2015 09:32 UTC
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Date: Fri, 16 Jan 2015 10:32:15 +0100
From: Alexandre Petrescu <alexandre.petrescu@gmail.com>
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Subject: [6lo] IID length in draft-ietf-6lo-btle-06.txt - why64?
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Hello, I wonder why is the length of the IID in draft-ietf-6lo-btle-06.txt set to 64 since the BTLE MAC address is just 48bit? Is there a problem if we set the IID length to 48? Because if we do, then we may have an advantage in using longer than 64 prefix lengths in the BTLE subnet - e.g. /65. This is helpful in networks at the very edge of the Internet - typically the prefix arriving from the Internet to the 6LBR is is of length 64. With such a prefix arriving to the 6LBR it is practically impossible to create another prefix of length also 64 beyond 6LBR, in the BTLE subnet. Hence we'd need a prefix length of /65 in the BTLE subnet. But a /65 in BTLE is impossible if the IID is of length 64. Let me illustrate this by way of comparison: 6LN \ ____________ /65 impossible \ /64 / \ 6LN ---- 6LBR ----- | Internet | / \____________/ / 6LN - with IID of length 64 - -------------------------------------------------------------- 6LN \ ____________ /65 possible \ /64 / \ 6LN ---- 6LBR ----- | Internet | / \____________/ / 6LN - with IID of length 48 - Alex PS: fyi a soon-to-be-RFC on the topic draft-ietf-6man-why64-08 "Analysis of the 64-bit Boundary in IPv6 Addressing"
- [6lo] IID length in draft-ietf-6lo-btle-06.txt - … Alexandru Petrescu
- Re: [6lo] IID length in draft-ietf-6lo-btle-06.tx… teemu.savolainen
- Re: [6lo] IID length in draft-ietf-6lo-btle-06.tx… Alexandru Petrescu
- Re: [6lo] IID length in draft-ietf-6lo-btle-06.tx… Sten Carlsen
- Re: [6lo] IID length in draft-ietf-6lo-btle-06.tx… Alexandru Petrescu
- Re: [6lo] IID length in draft-ietf-6lo-btle-06.tx… Sten Carlsen
- Re: [6lo] IID length in draft-ietf-6lo-btle-06.tx… teemu.savolainen
- Re: [6lo] IID length in draft-ietf-6lo-btle-06.tx… Alexandru Petrescu
- Re: [6lo] IID length in draft-ietf-6lo-btle-06.tx… Alexandru Petrescu
- Re: [6lo] IID length in draft-ietf-6lo-btle-06.tx… teemu.savolainen
- Re: [6lo] IID length in draft-ietf-6lo-btle-06.tx… Ole Troan
- Re: [6lo] IID length in draft-ietf-6lo-btle-06.tx… Alexandru Petrescu
- Re: [6lo] IID length in draft-ietf-6lo-btle-06.tx… Ole Troan
- Re: [6lo] IID length in draft-ietf-6lo-btle-06.tx… Alexandru Petrescu
- Re: [6lo] IID length in draft-ietf-6lo-btle-06.tx… Ole Troan
- Re: [6lo] IID length in draft-ietf-6lo-btle-06.tx… Alexandru Petrescu
- [6lo] IID length in draft-ietf-6lo-btle-06.txt - … Alexandre Petrescu
- Re: [6lo] IID length in draft-ietf-6lo-btle-06.tx… Gabriel Montenegro
- Re: [6lo] IID length in draft-ietf-6lo-btle-06.tx… Samita Chakrabarti
- Re: [6lo] IID length in draft-ietf-6lo-btle-06.tx… Alexandru Petrescu
- Re: [6lo] IID length in draft-ietf-6lo-btle-06.tx… James Woodyatt
- Re: [6lo] IID length in draft-ietf-6lo-btle-06.tx… Carsten Bormann