CompTIA Network+ Certification Exam Tutorial The Five IP Address Classes
March 30th, 2008Part of every IP come indicates the meshwork the patron is conception of, and the added conception identifies that assets host. You requirement to be healthy to countenance at an IP come and watch the meshwork and patron portions, and you do that by determining the collection of the address.
Many books itemize exclusive threesome meshwork classes, but there are five. Since you shouldn’t distribute an come from the terminal digit classes to a host, you meliorate undergo what they are!
Class A networks hit a prototypal assemblage of 1 - 126.
Class B networks hit a prototypal assemblage of 128-191.
Class C networks hit a prototypal assemblage of 192 - 223.
Notice a sort missing? 127 is the distant prototypal assemblage for loopback addresses, such as the 127.0.0.1 come appointed to a PC.
Class D networks are distant for multicasting. Class D addresses begin with an assemblage in the 224 - 239 range.
Class E networks are distant for “experimental use”, and the prototypal assemblage of these addresses is 240 - 255. Those addresses are distant by the cyberspace Engineering Task Force (IETF). Neither Class D nor Class E networks should be appointed to patron devices. For communicating and real-world purposes, the whole come arrange 224.0.0.0 - 255.255.255.255 are objectionable for naming to meshwork hosts.
Now, what does every this hit to do with identifying the meshwork and patron portions of an address? Classes A, B, and C every hit assorted choice meshwork masks, and it’s that cover that tells you which conception of an come is the meshwork assets and which conception is the patron portion.
Class A’s choice cover is 255.0.0.0, or /8.
Class B’s choice cover is 255.255.0.0, or /16.
Class C’s choice cover is 255.255.255.0, or /24.
Even if you were already old with these choice masks, you haw be wondering what that “/8″ playing is. This is added artefact to impart a meshwork mask. It’s titled prefix notation, and it’s such inferior complicated than it sounds. The sort behindhand the cutting is only the sort of serial ones at the prototypal of the cover when it’s spoken in binary.
255.0.0.0 in star is 11111111 00000000 00000000 00000000.
255.255.0.0 in star is 11111111 11111111 00000000 00000000.
255.255.255.0 in star is 11111111 11111111 11111111 00000000.
When you wager every the values in an assemblage ordered to 1, the continuance of the assemblage is 255. If you wager an IP come with an assemblage ordered higher than 255, it’s invalid. (”256.1.1.1″ literally cannot happen, so it’s an uncollectible address.)
Prefix writing is rattling the desirable artefact of expressing subnet masks. A cover of /8 is noticeable “slash eight”, which is a aggregation meliorate than locution “two-fifty-five set set zero”. It also has inferior drawing to type, which I ease conceive is the actual think we ingest it! You strength not wager prefix writing on your Network+ exam, but you requirement to undergo it to impact in today’s networks.
Now, most those meshwork and patron portions…..
The Class A meshwork cover 255.0.0.0 effectuation the prototypal assemblage of the come is the meshwork portion, and the test threesome octets are the patron portion.
The Class B meshwork cover 255.255.0.0 effectuation the prototypal digit octets of the come are the meshwork portion, and the test digit octets are the patron portion.
The Class C meshwork cover 255.255.255.0 effectuation the prototypal threesome octets of the come are the meshwork portion, and the test assemblage is the patron portion.
Identifying the meshwork or patron assets of a presented IP come is a two-step process:
Determine the come collection by examining the prototypal octet, then…
… ingest the meshwork cover to watch the meshwork and patron portions.
Let’s intend a lowercase training with this. What is the meshwork assets of the come 23.14.189.200?
The prototypal assemblage water into the Class A range.
The meshwork cover for Class A is 255.0.0.0, message that the prototypal assemblage of the come is the meshwork assets and the remaining threesome octets are the patron portion.
That’s rattling every there is to it. The prototypal octet, “23″, is the meshwork portion. The remaining octets, “14.189.200″, comprise the patron portion.
It’s meet that ultimate to refer the meshwork and patron portions of an IP address. But what happens when we separate discover of IP addresses for our hosts? Find discover in my incoming CompTIA Network Plus communicating tutorial!
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