Agreed! Mike W.
"timothy thielen" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > The best way for me to understand is to do the binary, and let the shortcuts > go hang. As someone once said to me "I'm not smart enough to do the > shortcuts" > > > Kage Roc wrote: > > > > I promise I will not be a knowledge leech, I will contribute > > what I know as well. Ofcourse I do have a question regarding > > IP Summaization: Up untill today I thought I had > > summarization down cold until I tried a few self made > > excercises. The formula I used to gather a summ address was > > 2n=x. Thats 2 to the n power equals x. > > x is the number of subnets that you want to summarize and n > > will be how much you subtract from the lowest mask of those > > subnets. for example: > > > > > > 216.52.146.136/30 > > 216.52.146.140/30 > > 216.52.146.144/30 > > 216.52.146.148/30 > > you can only summarize to where the bits are identical. Looking at the last > octet: > > 136=10001000 > 140=10001100 > 144=10010000 > 148=10010100 > > the boundary would be at /27, the total of the first three octets and the 3 > bits of the fourth. The summary route would be 216.52.146.128/27 > > If you use /28 for those networks, you're gonna get something funky. > > > > > using that formula the summ would be 216.52.146.136/28 which is > > not a valid route. Hoever that formula works here: > > 216.52.146.48/29 > > 216.52.146.56/29 > > > > summ route: 216.52.146.48 /28 > > > > here the last octets are: > 48=00110000 > 56=00111000 > > making the masked bits /28 (3 octets + 4 identical bits) > > > I guess my question is, what is the best/effective/convient way > > to derive summary addresses? Thanks for any input. > > > > If you're very lucky, you have the brain to do this silliness in your head. > Otherwise, just do the binary conversions and draw lines. > > --Tim, the pretty sure he got that right. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=42246&t=41998 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
