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RE: Spread Spectrum IP Addressing - SOURCE Address Field ROTATED|shifted? Left 2 Bits
From: "Keith Medcalf" <kmedcalf () dessus com>
Date: Sat, 03 Mar 2012 14:13:33 -0700
Is it April already? I though April Fools Day wasn't until next month. I did, I did. I did see a snake-oil salesman! --- () ascii ribbon campaign against html e-mail /\ www.asciiribbon.org
-----Original Message----- From: Guru NANOG [mailto:nanog.guru () gmail com] Sent: Saturday, 03 March, 2012 12:34 To: nanog () nanog org Subject: Spread Spectrum IP Addressing - SOURCE Address Field ROTATED|shifted? Left 2 Bits Common Misconception With Spread Spectrum IP Addressing the 32-bit Source Address Field is Shifted LEFT 2-bits by the originator of the packet. That Folds the IPv4 Legacy Address Space into 1/4th tsize table The lost 2-bits are stored in the Right-Most 2 bits of the 32-bit field and in other places in the IPv4 Header The Destination can easily recover the Source Address - if the proper algorithms are in use Responses blindly sent back to the shifted Source Address may fall into agile hands or not With the advanced Spread-Spectrum techniques, additional addressing bits are created from the noise intentionally stored in the Right-Most 2 bits NANOG Operators buying /8s or /6s may want to look at the Spread-Spectrum CODE in the Linux-based CPE Routers The following table is deprecated and 1/4th the size: http://www.iana.org/assignments/ipv4-address-space/ipv4-address-space.txt With Spread-Spectrum collisions and mis-directions are OK and expected but other techniques ensure the packets get to the right place. http://NANOG.GURU
Current thread:
- Spread Spectrum IP Addressing - SOURCE Address Field ROTATED|shifted? Left 2 Bits Guru NANOG (Mar 03)
- RE: Spread Spectrum IP Addressing - SOURCE Address Field ROTATED|shifted? Left 2 Bits Keith Medcalf (Mar 03)
- Re: Spread Spectrum IP Addressing - SOURCE Address Field ROTATED|shifted? Left 2 Bits Tim Jackson (Mar 03)
- Re: Spread Spectrum IP Addressing - SOURCE Address Field ROTATED|shifted? Left 2 Bits Robert Bonomi (Mar 03)
- Re: Spread Spectrum IP Addressing - SOURCE Address Field ROTATED|shifted? Left 2 Bits Valdis . Kletnieks (Mar 03)
- Re: Spread Spectrum IP Addressing - SOURCE Address Field ROTATED|shifted? Left 2 Bits Brielle Bruns (Mar 04)