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Home > Archive > CCNA > July 2000 > dotted decimal, hexadecimal, binary help with conversion pls?
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dotted decimal, hexadecimal, binary help with conversion pls?
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| hi all,
Can someone help me with the explanation and conversion of dotted decimal, hexadecimal and binary with respect to IP, MAC and IPX? Help greatly appreciated  | |
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| Below is a link to a whitepaper on the 3Com site.
When nothing else made sense to me, this paper did the trick for IP and subnetting:
http://www.3com.com/nsc/501302.html
I also recommend the following site:
http://www.learntosubnet.com
I'll try to find my other references on Tuesday and post them here for you.
Good Luck!
Rico
NOTICE:
The above references may contain copyrighted material. I urge you to comply with any and all restrictions, if they exist, on such material. | |
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| bravo rico...at cursory glance those are good and thorough study guides for subnetting...one is in acrobat and the other streaming media....i tip my hat 2yah | |
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| Rico,
The 2 website mention above talks about subnetting and other stuff which I already know. What i really want to know is the meaning of hexadecimal with relations to IP and MAC address. Hope the following can help relate to what answers I'm looking for.
what is the diff between ip and mac address? A) ip 32 bit hexa decimal, mac 48 bit - dotted decimal B) ip 32 bit hexa decimal, mac 48 bit - hexa decimal c) ip 32 bit dotted decimal, mac 48 bit - hexa decimal* d) ip 32 bit hexa decimal, mac 48 bit
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| Kingsway,
MAC addresses are factory-assigned hardware addresses and govern OSI layer 2 (Data Link Layer) functions, such as bridging and switching.
IP addresses are locally-assigned logical addresses and are used for OSI Layer 3 (Network Layer) functions such as routing.
To give you an example of what IP is used for, when you enter this site's URL into your browser, a DNS server is consulted to convert the domain name to an IP address. This IP address indicates what major network, subnetwork, and ultimately what node (or host) the domain resides in. Routers use this IP address information to route packets to the correct destination.
MAC addresses, however, are used by the network interfaces themselves to tell each other apart. When you have ten machines on a small Ethernet network, they are all listening on the same wire. The only way an interface (such as a Network Interface Card, or NIC) knows it has a message is when it hears its own MAC address in the header of an Ethernet frame.
MAC addresses are composed of an OUI (Organizational Unique Identifier) and a serial number. The OUI is assigned by a central body and is sometimes referred to as a Vendor code. The rest of the MAC address is a serial number that is unique to the vendor. This ensures that no two devices in the world have the same factory-assigned MAC address.
As for decimal and hexadecimal and binary, it's all rather simple:
Decimal = Base 10
Examples:
1
10
100
1,000
10,000
Each position represents a power of 10 and can only store a digit between 0 and 9. When doing math, if the sum of any column of numbers is greater than 9, we must carry over into the next column to the left. It is important that you think of this in these terms, because we take it for granted that decimal is the only real number system. Computers don't look at it that way.
Binary = Base 2
Examples
0000 = 0
0001 = 1
0010 = 2
0011 = 3
0100 = 4
0101 = 5
0110 = 6
0111 = 7
Each position is a power of 2 and can hold a digit between 0 and 1. When doing math, if the sum of one column results in a number larger than 1, we must carry over to the next column to the left. Same as in Decimal, just working with a much smaller set of numbers. As a result, more digits are required to represent a number than in decimal.
Hexadecimal = Base 16
Examples
00 = 0
01 = 1
02 = 2
03 = 3
04 = 4
05 = 5
06 = 6
07 = 7
08 = 8
09 = 9
0A = 10
0B = 11
0C = 12
0D = 13
0E = 14
0F = 15
10 = 16
Every position is a power of 16 and can hold any digit between 0 and F (0 and 15). When doing math, if the sum of any column is greater than 15 we must carry over into the next column to the left. Same as decimal, only with a larger set of numbers. As a result, large numbers can be written with fewer digits than in decimal.
Example:
FFFF = 65535 (4 digits versus 5)
FF = 255 (2 digits versus 3)
FFFFFFFF = 4294967295 (8 digits versus 10)
When dealing with MAC addresses, for example,
you are dealing with a 48 bit address. You have the choice of writing it any whay you'd like:
Example: 00-1C-2F-46-29-1B
In binary:
00000000 00011100 00101111 01000110 00101001 00011011
In hexadeximal:
001C2F46291B
In decimal:
5,088,094,591 (my desired salary, in US Dollars)
In dotted decimal:
0.28.194.70.41.27
Industries like standards. In the case of a MAC address, people chose to stick to dashed hex notation: 00-1C-2F-46-29-1B
All these numbers mean exactly the same thing, but because the numbers are so astronomically large, we just need a convenient way to express them, that's all.
Hope this helps.
Skip
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Whatever the mind of man can conceive and believe, it can achieve.
[This message has been edited by TheSkipster (edited 07-31-2000).] | |
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| Skipster:
You should copy and paste that for your future study guide
You did it again - above and beyond for the group!
Test in 4 hours!
Rico
[This message has been edited by Rico (edited 07-31-2000).] | |
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| I should write a book, shouldn't I?
Skip |
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