Why IP?
. Every device connected to internet should have an identifier called IP Address.
. With the help of these IP Addresses, users communicate with each other over the world.
. IPs are of two types IPv4 and IPv6 which differ in supporting number of address spaces it can provide.
. IPv4 supports 4.3 billion address spaces and Ipv6 supports plenty of addresses which are sufficient for future use.
Who provides IP Address?
. Users are assigned IP Addresses by Internet Service Providers (ISP).
. ISPs obtain allocations of IP addresses from Local Internet Registry (LIR) or National Internet Registry (NIR) or Regional Internet Registry (RIR).
. Internet Assigned Numbers Authority (IANA) globally coordinates the IP Addressing System.
. IANA assigns blocks of IP to the RIR which is of 5 regions which is managed by Internet Corporation for Assigned Numbers and Names (ICANN).
| RIR | Abbreviation | Areas covered |
|---|---|---|
| AFRIC | African Network Information Center | African region |
| APNIC | Asia and Pacific Network Information Center | Asia, Australia, New Zealand and neighbouring countries |
| ARIN | American Registry for Internet Numbers | Canada, USA, Caribbean region |
| LACNIC | Latin America and Caribbean Network Information Center | Latin America, Caribbean region |
| RIPE NCC | Reseaux IP European Network Coordination Center | Europe, Middle East, Central Asia |
. RIR assigns IP address to the next level NIR.
. NIR assigns IP addresses to LIR and also to the ISPs and end users directly.
. Hierarchy of assignment of IP numbers is as shown below:
Purchasing IP blocks:
. When we wanted to purchase IP blocks, we need to contact the RIR as per our region.
. IP addresses are assigned to networks in different sizes of blocks.
. Size of block is written after oblique (/), which shows number of IPs contained in that block.
. IP addresses are assigned to networks in different sizes of blocks.
. Size of block is written after oblique (/), which shows number of IPs contained in that block.
. Example: If ISP assigned /24, they would receive 32-24=8=>2^8 (256) addresses.
. By contacting to particular RIR eg APNIC, we can follow further steps to purchase IP block.
. Requesting for IP address from LACNIC: Type in "ip request for lacnic" in browser.
