North American Network Operators Group

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Re: What is the most standard subnet length on internet

  • From: bmanning
  • Date: Fri Dec 19 01:10:27 2008

On Fri, Dec 19, 2008 at 02:40:47AM +0000, l l9l wrote:
> However, what I am really wondering is what is the most standard subnet length that always can be guaranteed through Internet. less than /24 bit ?
> 

	while one can get away w/ /24s (if that is all one has) for many places,
	I suspect that there will be increasing pressure to drop more specific
	/24s as folks routing tables grow.

	your question, "...length that can be guaranteed through the Internet." 
	argues for fairly short netmasks, e.g.  a /16 is likley to be accepted
	by most folks while very short masks, e.g.  /8 or smaller are likly to
	be seen with some level of consideration since so very few prefixes of 
	that size are likely to be origin-sourced (often proxy aggregates from
	transit parties)...

	as others have pointed out - this "acceptable" value is fluid, changing 
	over time and variable between ISPs.  Creating a static policy is likely
	to be flawed.

--bill (crawling out from under his rock, blinking in the bright lights)