Appendix E - Ip Address Range And Subnets; Ip Address And Subnet Masks - Dedicated Micros DV-IP Decoder Setup Manual

Appendix E – IP Address Range and Subnets
It is possible to set a range of IP address within the Firewall that will have access to the DV-IP
Decoder. The following details how the address range and subsequent subnet is calculated and
can be used in conjunction with the Configuration section of this manual.

IP address and Subnet Masks

An IP address is a 32 bit address that is read by the network devices (switches, hubs, routers) in
a binary format, however to make life simpler for Network Administrator, IP addresses are
displayed in a decimal format.
The same applies to subnet masks, these to are 32 bit addresses and are identified by the
network devices in binary format, but for written in a decimal format.
The 32 bits are grouped in to four 8 bits (an Octet) to give us the IP address format we are used
to:
Binary Format
11000000.10101000.00000011.00000001
11111111.11111111.11111111.00000000
The binary format of the IP address uses 1's and 0's and within an octet it is possible to identify
256 decimal numbers from 0 to 255.
128 64
1 1
0 0
An IP address along with its subnet mask is made up of two parts; Network ID and Host ID. If
we use our example IP address, 192.168.3.1 we can see the network ID and the host ID;
IP Address
192.168.3.1
255.255.255.0
Wherever the subnet gives a value of 255 (all 1's) it 'masks' out the IP address octet and
therefore represent the Network part of the overall IP address. Hence the reason the above
example takes the first three octets as the network ID and the last octet as the host ID.
Dedicated Micros
32 16
1 1
0 0
Network ID
192.168.3
255.255.255
Decimal Equivalent
192.168.3.1
255.255.255.0
8 4
1 1
0 0
2 1
1 1
0 0
Host ID
.1
.0
Decimal
255
0
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