About IP Addresses. 193.0.0.131 196.216.2.1 192.149.252.7 200.160.2.15 202.12.29.20 192.0.0.214 206.131.253.68 192.0.34.163 .

About IP Addresses

193.0.0.131

196.216.2.1

192.149.252.7

200.160.2.15

202.12.29.20

192.0.0.214

206.131.253.68

192.0.34.163

www.nro.net

www.afrinic.net

www.arin.net

www.lacnic.net

www.apnic.net

www.ripe.net

www.isoc.org

www.icann.org

On the Internet, you are nothing but an IP address!

202.12.29.142

What is an IP Address?

An Internet Protocol (IP) address is a numeric identifier that

includes information about how to reach a network location

through the Internet routing system.

IPv4 and IPv6

Internet Protocol version 4

Internet Protocol version 6

32-bit* number 128-bit* number

Dotted Decimal Notation:192.0.2.0

Hexadecimal Notation:2001:DB8::/32

4 billion network addresses

16 billion-billion network addresses

* bit = binary digit

IP Addresses Are:

• Necessary for Internet routing

• A finite common resource

• Not dependent upon the DNS

• Not “owned” by address users

– Not property

– Cannot be bought, sold, traded…

– Provided on a temporary basis

– Returned to registry or provider when no longer required

IP Addresses Are:

How does an IP address make the

Internet work?

What is Routing?

Routing is the act of moving information across an

internetwork from a source to a destination.

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Each computer communicates with the other computers on its network, creating a total of 15 connections.

Six computers need to communicate with each other.

On a larger network, individual connections become unmanageable.

Point-to-Point Networking

Network

Instead, the computers can connect to a single router. ``

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Router

Interconnected Networks

Each network can link to other networks via its router.

172.25.1.4 192.23.9.6

201.32.16.10

Each segment receives IP addresses.

163.37.56.21

172.25.1.4 192.23.9.6

201.32.16.10 163.37.56.21

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Administrative Grouping

Registries provide Internet number resources to help divide internetworks into interconnected, autonomous groups of devices.

172.25.1.4 192.23.9.6

201.32.16.10

163.37.56.21

AS 1234 AS 2345

AS 3456

Groups of devices with a single, clearly defined routing policy may be assigned an Autonomous System Number (ASN).

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Traffic202.12.29.0/24 Announce202.12.29.0/24

Internet Address Routing

Internetwork Routing Table

4.128/9

60.100/16

60.100.0/20

135.22/16

…

Internetwork Routing Table

4.128/9

60.100/16

60.100.0/20

135.22/16

202.12.29.0/24…

202.12.29.0/24

1. The network announces an IP address range.

2. The range is added to a specific table within a router.

3. The router can redistribute information to devices within the network.

The Internet

Internet Address Routing

Traffic202.12.29.142

Routing Table

202.12.29.0/25

202.12.29.128/25Local Router

202.12.29.142

202.12.29.0/24

1. Traffic enters the network according to the routing table.

2. The local router directs traffic to the appropriate device according to its own routing table.

Global Internet Routing

Network

Network

Network

Network

Network

Network

Network

Network

Network

Network

Network

Internetwork Routing Table

4.128/9

60.100/16

60.100.0/20

135.22/16

…With a coordinated numbering system, you can build a network of networks.

What is the Domain Name System (DNS)?

The Domain Name System (DNS) is a means of storing and

retrieving information about host names and IP addresses in a

distributed database.

IP Addresses Are Not Domain Names

IP Address Domain Name

Computer-friendly People-friendly

Identifier Reference

Unique number identifies computer on Internet

Host name mapped to an IP address

Used for routing Not used for routing

2001:0C00:8888::My Computer www. cernet.cn

2001:0400::

www.cernet.cn? 202.112.0.462001:0400::

Using Domain Names

The Internet

DNS

1. My Computer asks the DNS where to find www.cernet.cn

2. The DNS provides the IPv4 or IPv6 address for the requested URL.

3. My Computer queries the appropriate server for the IP address provided by the DNS.

Visit the NRO booth or contact the NRO for more

information:

http://www.nro.net

nro@nro.net