Every device that connects to the internet uses a unique address called an IP address, which works very similar to a home/location address. Pieces of data, called “packets”, are transferred via the internet between machines, which in turn gives us the fully functioning interior workings of the online community. In order for two machines, or devices to communicate via the internet, they must transfer these “packets” of data back and forth. Unfortunately the data “packets” can not be transferred if the devices do not each have their own unique address.
. “IPv4″ stands for “Internet Protocol version 4. IPv4 is older, more supported version of the internet address procedure. But ultimately, there are no longer any free IPv4 addresses, meaning all of them have been occupied or taken up.
· Older version.
· IPv4 only supports a maximum 32 bit internet address, which translates to 2^32 IP addresses available for assignment (about 4.29 billion total).
· 4 bytes in length.
· variable size – time-consuming to handle
· by network classes A, B, C (large, medium, small nets), local use limited to link only
· point-to-point communication, local broadcast (depends on physical link features); limited multicast experimental any cast (not globally available)
· Header does not identify packet flow for QoS handling by routers.
· Both routers and the sending host fragment packets.
· Header includes a checksum.
· ARP uses broadcast ARP request to resolve IP to MAC/Hardware address.
· Internet Group Management Protocol (IGMP) manages membership in local subnet groups.
· Broadcast addresses are used to send traffic to all nodes on a subnet. Configured either manually or through DHCP. Must support a 576-byte packet size (possibly fragmented).
IPv6 stands for Internet Protocol version 6.
· IPv6 utilizes 128 bit web addresses. Making a maximum 2^128 available addresses: 340,282,366,920,938,000,000,000,000,000,000,000,000. This is approximately three hundred and forty trillion, trillion, trillion addresses. To use up every single IPv6 addresses we would need to stack ten billion computers on top of each other over the entire world including the sea.
· Addresses are 16 bytes in length
· fixed size (40 octets) – more efficient
· IPv4 compatibility hierarchical by registry, provider, subscriber, and subnet hierarchical by geographic region, local use by link or site
· over 70% of addresses reserved for future expansion
- Multicast (sends to many interfaces at once) by link, by site, by organization, by any grouping
· Header contains Flow Label field, which Identifies packet flow for QoS handling by router.
· Routers do not support packet fragmentation.
· Header does not include a checksum.
· Optional data is supported as extension headers.
· Multicast Neighbor Solicitation messages resolve IP addresses to MAC addresses.
· IPv6 uses a link-local scope all-nodes multicast address.
· Does not require manual configuration or DHCP. Must support a 1280-byte packet size (without fragmentation).