subnetting ip

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Well it all starts with how many ip adressses you need and how many different networks. You determine that first and based on that you can further subnet the network. Lets say that your location will require 3 subnets and each of them need 50 ip adresses. You owould have to set up a scheme where you subnet your current submask and at the same time considering that you need a certain amount of ipadresses. Subnetting is not the easiest part of setting up the network. I might be able to give you some more pointers (and docs to research this) shoot me an email if you like

If I'm interpreting your question correctly, you're trying to determine what range of IP addresses are "yours" to use in your network. Given the base address and subnet mask you have, your available range is from 10.0.0.0 thru 10.0.15.255.

I find it easier to think in binary or hex terms, rather than decimal and, in hex your assigned subnet is: FF.FF.F0.00. This mask fixes the first five character values as your office network address, leaving you free to assign the remaining three character values to hosts in your network. Depending on the size of your network, you may find it useful to further subnet to make internal management simpler. You should not use any host address ending in .0 or .255, however, as these are for broadcastuse.

A good source to learn subnetting is http://www.learn2subnet.com. Hope it helps.

Each group of an IP address, seperated by a period, is represented by a number...ie 255.255.240.0. This
actually references 4 groups of hexadecimal values, referenced in decimal format...
hence ip addressing is a decimal representation of hexadecimal values.
The Address 255 is represented such as this:
bit position/decimal value
7/128 6/64 5/32 4/16 3/8 2/4 1/2 0/1
1 1 1 1 1 1 1 1
So that if the bit position in the IP address has a value of one, then it's decimal value is added to the whole number of the addresss....
1 1 1 1 1 1 1 1
128+64+32+16+8+4+2+1=255 or:
1 1 1 1 0 0 0 0
128+64+32+16+0+0+0+0=240
make sense?
regarding the subnet mask you have been given: 255.255.240.0
address group 1 = 255, all bit positions are set, and network packets which reference this group of bits will be masked by ones and disregarded by the router,
address group 2 = 255, the same applies
THE NEXT IS THE KEY...
Address group 3 = 240, which masks the first four address bits, ie.
bit 7/128, bit 6/64 bit 5/32 and bit 4/16 are all set to ones thus...
128+64+32+16 = 240, therefore, the first four addressing bits will be masked, which allows you to use address bits
3/8, 2/4, 1/2, 0/1 for your workstations
PLUS ALL 8 address bits from address group 4
meaning 12 address bits are available to you for assigning to network nodes.
Thus:
allowing 12 address bit positions for use by workstations, represented by the following formula = "2 to the powerof 12 minus 2".(addresses 255 and 0 are not readily available)
meaning 4093 individual NETWORK NODE addresses are available to you using THIS subnet mask showing bit position over value
11 10 9 8 7 6 5 4 3 2 1 0
(2048+1024+512+256+128+64+32+16+8+4+2+1)
this is the range of sddresses for your router: 10.0.241.xxx to 10.0.254.254
This becomes the default gateway address for your network

You have been asked to implement a block of IP addresses reserved by the The Internet Assigned Numbers Authority (IANA) for private networks.

Block 10.0.0.0 - 10.255.255.255
IP Address 10.0.0.0 This is a class A address
Binary Equivalent 00001010.00000000.00000000.00000000
00001010.00000000.00000000.00000000 is 32 bits long
00001010 is 8 bits long

You have been told to subnet IP 10.0.0.0 using subnet mask 255.255.240.0

Masked bits 20 (first 20 are network portion)
Subnet bits 12 (last 12 are host portion)
Max number of subnets 4094
Max number of hosts PER subnet 4094 (must be a big office hehehe)

First 6 subnets from within max number of 4096 subnets

1 10.0.16.0 10.0.16.1 - 10.0.31.254 10.0.31.255
2 10.0.32.0 10.0.32.1 - 10.0.47.254 10.0.47.255
3 10.0.48.0 10.0.48.1 - 10.0.63.254 10.0.63.255
4 10.0.64.0 10.0.64.1 - 10.0.79.254 10.0.79.255
5 10.0.80.0 10.0.80.1 - 10.0.95.254 10.0.95.255
6 10.0.96.0 10.0.96.1 - 10.0.111.254 10.0.111.255

Exam: Subnet #1
Subnet ID 10.0.16.0
Host Range 10.0.16.1 - 10.0.31.254
Subnet Broadcast 10.0.31.255
Gateway or router typically assigned 10.0.16.1

Download free IPCalc from http://www.net3group.com

Research IP addressing http://www.rad.com/networks/1994/ip_addr/tcpip2.htm

Use operating system help for assistance in setting up TCP/IP on clients/servers

Research Microsoft/Novell/Other Knowledge Bases for detailed HOWTO's

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