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As someone who works with Google Analytics, it is often necessary to block IP addresses for a particular account. If like me, you are ever given an IP address with a network prefix to exclude from a Google Analytics account, it will often be given to you in the following slash notation format:. But just in case you don't have access to these then here is how you do it the good old fashioned way.

We don't need to know how to divide up a range of addresses into different subnets or how to transfer one set of addresses to another IP range. We just need to know how to calculate the range of addresses when only given an IP with slash notation.

You may find it easier to write these calculations down so you will need a piece of paper, a pen or pencil and possibly a calculator! Lets' start with some background theory. The next passage is going to explain the fundamentals of IP's and subnets and the relationship between their decimal and binary value.

Once you're finished you should be confident in converting an 8 bit octet into binary — the basis of all subnetting re convert ip address in binary to std format.

An IP address is a unique identifier given to a single device on an IP network. An IPv4 address consists of a bit number which theoretically provides around 4. But to make such a large address block easier to handle, it re convert ip address in binary to std format chopped up into four 8-bit numbers, or decimal "octets," separated by a full stop. This is called dot decimal notation. Instead of 32 binary base-2 digits, which would be too long to read, it's converted to four base digits.

Octets are made up of numbers **re convert ip address in binary to std format** from 0 to Think of an IP address as 4 blocks of numbers. Each blocks value is composed of the single use of any re convert ip address in binary to std format from the following: These values all go into making an 8 bit octet and when adding any combination of these together each number can only be used once a value of 0 — can be made.

These octets are most easily understood when converted to binary. Binary works by assigning either re convert ip address in binary to std format 1 or 0 to each value within the octet depending on if the value is needed. For instance the re convert ip address in binary to std format octet in the example IP address above is To convert this to binary we would need to look at the number in relation to its binary bits.

With this theory in place we can now move on to explaining the whole process of converting an IP address with a network prefix into a Google Analytics friendly format. The subnet mask not only determines the size of a subnet, but it can also help you determine where a subnet starts and finishes if re convert ip address in binary to std format given any IP address within that subnet.

The reason it's called a subnet "mask" is that it literally masks out the host bits and leaves only the Network ID that begins the subnet. Once you know the beginning of the subnet and how big it is, you can determine the end of the subnet, which is the Broadcast ID.

The subnet simply tells you how many IP addresses there are on any given subnet. The routing prefix of an address is written in a form identical to that of the address itself. This is called the network mask, re convert ip address in binary to std format netmask, of the address.

For example, a specification of the most-significant 14 bits of an IPv4 address, If this mask designates a subnet within a larger network, it is also called the subnet mask. This form of denoting the network mask, however, is only used for IPv4 networks. In simple terms, in order to calculate the subnet mask from a network prefix we must count left along the number of bits to add up the octal values:.

The wildcard is basically the remaining value of the unused bits from the subnet mask. It is not commonly used but is a good way of double checking your sums and also when calculated gives you an easy way of working out the end of the network range.

If you add up the unused bits then this value when added to the subnet mask would give you: Looking at the diagram above we can see that only the first 14 bits were used, this means the wildcard consists of the last 18 bits. By switching the first 14 bits back to 0's and by switching the last 18 bits 0's to 1's this gives us the inverse of the subnet:. We now have all the values we need to calculate all the address that tell us what the network range is!

When adding together binary values place the IP value above the subnet mask. The only value that can be used is a 1 or a 0. The outcome of a sum can only be a 1 if two 1's are added together anything else is always represented as a 0. To finally work out what the last address is in the network the broadcast IP we must add the numbers together of the Wildcard and the Network Address previously calculated.

Adding the decimal values together which gives us:. Part 1 of 2: If like me, you are ever given an IP address with a network prefix to exclude from a Google Analytics account, it will often be given to you in the following slash notation format: But how exactly do you do this?

Isn't it just the same as excluding a regular IP address in GA? If you're in a hurry the easy way is with a calculator, such as these: Fundamentals of IP's and Subnets: Convert the IP address to binary The address is: Represent the network prefix in binary and convert to decimal Subnet Mask The subnet mask not only determines the size of a subnet, but it can also help you determine where a subnet starts and finishes if you're given any IP address within that subnet.

The network prefix is: The subnet mask is therefore: By switching the first 14 bits back to 0's and by switching the last 18 bits 0's to 1's this gives us the inverse of the subnet: Add the binary IP address to the subnet mask When adding together binary values place the IP value above the subnet mask.

Converted back to decimal this is: Add the Wildcard value to the network address To finally work out what the last address is in the network the broadcast IP we must add the numbers together of the Wildcard and the Network Address previously calculated. Adding the decimal values together which gives us: Summary Filling in the gaps for completions sake here is what we now know: Contact Us Do you have a challenge for us to solve?

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