Diff: ClasslessInterDomainRouting

Differences between current version and predecessor to the previous major change of ClasslessInterDomainRouting.

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Newer page: version 9 Last edited on Thursday, August 12, 2004 4:20:13 pm by PerryLorier
Older page: version 8 Last edited on Wednesday, January 28, 2004 3:27:41 pm by AristotlePagaltzis Revert
@@ -1,12 +1,12 @@
 When the InterNet was first invented they decided that since they'd be lucky to have perhaps 1,000 computers on the Internet, that they could do some smart stuff with the IP addresses. So the first few bits of an [IP] address said how large the network the IP was in was. 
 |^__Bits__|^__Name__|^__Size__|^__Bit length__|__Range__ 
-|<|Class A|128 networks of 16777216 hosts each|/8|>...0 -  
-|<10|Class B|2^14 networks of 65536 hosts each|/16|>128...0 -  
-|<110|Class C|2^21 networks of 256 hosts each|/24|>192...0 -  
-|<1110|Class D|2^28 multicast ID's| |>224...0 -  
-|<11110|Class E|2^27 Reserved addresses| |>240...0 - 
+|<|Class A|128 networks of 16777216 hosts each|/8|>.../1 -  
+|<10|Class B|2^14 networks of 65536 hosts each|/16|>128.../2 -  
+|<110|Class C|2^21 networks of 256 hosts each|/24|>192.../3 -  
+|<1110|Class D|2^28 multicast ID's| |>224.../4 -  
+|<11110|Class E|2^27 Reserved addresses| |>240.../5 - 
 There was a lot of use of Class C networks since a lot of people had about 250 odd machines, and a lot of people needed more than 250 machines, but less than 65530ish machines and they ended up using Class B addresses, however not many people required more than that. Now half the address space was "Wasted" reserved for "A" spaces and B and C spaces were running out fast. So the idea was to stop using the class bits and store the network information independently. This also let them give out ranges larger than a /24 (254 usable addresses), but smaller than a /16 (65534 useable addresses) 
 Many large organisations have (or used to have) class A networks assigned to them - a couple of quick examples are many universities (eg StanfordUniversity) and some car manufacturers (eg Ford - reserved a class A in expectation that all their cars would eventually have a unique IP address).