any interesting/useful resources available to IPv6 only?

Doug Barton dougb at
Mon May 6 02:31:37 UTC 2019

On 5/3/19 1:33 PM, Mohammad Khalil wrote:
> Hello all
> I have prepared something in the past you might find useful (hopefully).

First, it's considered rude to send attachments of any size to a mailing 
list, never mind one that's almost 2 megs in size. Much better to put it 
on a web site somewhere and send a URL.

Second, I normally wouldn't respond to something like this, except that 
there are so many errors and bad ideas in your document that I felt 
compelled to respond lest someone find it in the archives and rely on 
it. I will assume that your intentions were good here, however your 
results are dangerous, in the sense that someone reading your document 
would be worse off than if they had not read it.

Taking one tidbit from one of your early paragraphs, "The IPv6 protocol 
creates a 128-bit address, four times the size of the 32-bit IPv4 
standard." There is, sort of, a sense in which you could say that the 
addresses themselves are four times the size, but it creates a dangerous 
impression that the total address space of IPv6 is only four times the 
size of IPv4; and it's the address space that is the thing actually 
worth talking about.

Many of your other errors also involve math, which suggests a lack of 
understanding of basic networking concepts, binary math, etc. For 
example, "With 264 available addresses per segment, it is highly 
unlikely to see prefix lengths shorter than /64 for segments that host 
end systems." A /64 segment in IPv6 has 2^64 address, or the entire IPv4 
address range, squared. Maybe you meant to say 2^64 and forgot the 
exponent indicator? Given that you correctly identify exponents in other 
sections, it's hard to tell.

The document is also out of date in regards to the latest protocol 
changes, deprecations, etc.; and further out of date in regards to how 
operators are actually implementing IPv6.

Again, sorry to pile on ...

If anyone is looking for a pretty good introduction to the basics of 
IPv6 the Wikipedia article is a good start.

hope this helps,


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