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‫Probably the most well-known network layer protocol is, of course, IP or Internet protocol.

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‫As I mentioned in the beginning of the course.

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‫The Internet protocol or IP is responsible for addressing hosts.

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‫Encapsulating data into packet or data grams, including fragmentation and reassembly.

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‫And routing packets from a source host to a destination host across one or more IP networks.

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‫So like other layer three protocols, IP is connection less, which means it doesn't care whether the

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‫packet has reached the destination or not.

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‫That's what layer four is for.

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‫All right.

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‫So there are two versions of IP that currently co-exist within the global Internet.

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‫IP version four or IPV four and IP versions six or IPV six.

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‫IP addresses are made up of binary values and drive the routing of all data over the internet.

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‫IPV four addresses are 32 bits long and IPV six addresses are 128 bits long.

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‫Right now, we're going to see each of the versions in detail.

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‫But before we move on, let's compare the main features of each version.

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‫IPV four is a 32 bit address and IPV six is a 128 bit address.

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‫Now, theoretically, you can address two to the power of 32 devices in IPv4, which is about 4.3 billion.

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‫Right.

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‫In IPV six.

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‫On the other hand, you can address two to the power of 128 devices, which is Well, well, let's see,

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‫why don't you just do the math on your own?

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‫So IPv4 is represented by the decimal equivalent of four octets separated by dots.

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‫The biggest number one can make with eight binary digits is two to the power of eight minus one, which

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‫means 255.

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‫So each octet can be any number from 0 to 2 five five.

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‫Right.

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‫Now 128 bit IPV six addresses are written using hexadecimal as opposed to dotted decimal in IPv4.

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‫So because a hexadecimal number uses four bit, this means that an IPV six address consists of 32 hexadecimal

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‫numbers.

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‫These numbers are grouped in fours, giving eight groups or blocks.

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‫The groups are written with a colon as a separator.