At 8:03 PM -0400 6/30/02, Chuck wrote: >""Howard C. Berkowitz"" wrote in message >[EMAIL PROTECTED]">news:[EMAIL PROTECTED]... >> At 8:44 PM -0400 6/29/02, Priscilla Oppenheimer wrote: >> >At 12:49 PM 6/29/02, Michael L. Williams wrote: >> >>I have successfully used both an "all-zeros" and an "all-ones" subnet on >> >>Windows 9x. (192.168.0.0/24 and 192.168.255.0/24) Works fine. >> > >> >Those aren't subnets, though, since it's class C. >> > >> >Priscilla >> >> Ah, Priscilla, Priscilla, Priscilla. And all along I respected you >> because I thought your design thinking had no class. >> >> It would be accurate to say 192/8 is the traditional Class C space, > >CL: 192/3? "Class C" space includes anything from 192/8 through 223/8 Am I >constructing the CIDR block correctly?
Strictly, yes. But there are historical issues here. 192/8 was the only part widely assigned before there was concern about address exhaustion, and today is called "the swamp", with that part of 192/8 greater than /24 called the "toxic waste dump". At the start of the CIDR effort, the swamp took up 50% of the routing table, and the toxic waste dump took up 50% of the swamp. By the time there were significant allocations from the rest of the traditional class C space, registries were asking for much more justification, and also might assign CIDR blocks. > >CL: also, in a situation where it matters, would an ISP advertsie 192/8, >recognizing it contains defined private space? I can't see any reason why anyone would advertise 192/8. Large chunks of it, yes, and generally very poorly aggregated. At the time 192/8 was being allocated, if you needed more space, you'd typically get a traditional class B assignment. > > >> with the assumption of a /24 mask. To have shorter masks in that >> space does imply CIDR awareness, but there can still be significant >> problems -- and carrier filtering issues -- merely because something >> is in 192/8. >> >> Ironically, I once had a /22 in 192/8, which was generally subnetted >> into /25's. There were a couple of sites where I could have used a >> /24, but chose not to because any /24 tends to draw unneeded > > attention of the Address Vigilantes. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=47811&t=47670 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]