Slide 1

Internet Routing How It Works Prepared and Presented by the NRO On Behalf of the RIRs AfriNIC, APNIC, ARIN, LACNIC, RIPE NCC Slide 2 Routing How It WorksGovernment Advisory CommitteeJuly 2005 Definitions Routing The act of moving information across an internetwork from a source to a destination. Domain Name System [DNS] A means of storing and retrieving information about hostnames and IP addresses in a distributed data base. Slide 3 Point-to-Point Networking Routing How It WorksGovernment Advisory CommitteeJuly 2005 Slide 4 Point-to-Point Networking Routing How It WorksGovernment Advisory CommitteeJuly 2005 Slide 5 Point-to-Point Networking Routing How It WorksGovernment Advisory CommitteeJuly 2005 Slide 6 Point-to-Point Networking Routing How It WorksGovernment Advisory CommitteeJuly 2005 Slide 7 Point-to-Point Networking Routing How It WorksGovernment Advisory CommitteeJuly 2005 Slide 8 Point-to-Point Networking Routing How It WorksGovernment Advisory CommitteeJuly 2005 Slide 9 Point-to-Point Networking Routing How It WorksGovernment Advisory CommitteeJuly 2005 6 ! / 2! * ((6 2)!) = 15n! / p! * ((n p)!) = c 60 ! / 2! * ((60 2)!) = 1,770 600 ! / 2! * ((600 2)!) = 179,700 Slide 10 Routing How It WorksGovernment Advisory CommitteeJuly 2005 Network Slide 11 Routing How It WorksGovernment Advisory CommitteeJuly 2005 Inter Connected Networks Slide 12 Routing How It WorksGovernment Advisory CommitteeJuly 2005 Routed Internetwork 172.25.1.4 192.23.9.6 201.32.16.10163.37.56.21 Slide 13 Routing How It WorksGovernment Advisory CommitteeJuly 2005 Using DNS 172.25.1.4 192.23.9.6 201.32.16.10 163.37.56.21 Slide 14 Routing How It WorksGovernment Advisory CommitteeJuly 2005 Administrative Grouping 172.25.1.4 192.23.9.6 201.32.16.10 163.37.56.21 Slide 15 Routing How It WorksGovernment Advisory CommitteeJuly 2005 Autonomous Systems 172.25.1.4 192.23.9.6 201.32.16.10 163.37.56.21 AS 1234 AS 2345 AS 3456 Slide 16 Routing How It WorksGovernment Advisory CommitteeJuly 2005 Routing Announcement 172.25.1.4 192.23.9.6 201.32.16.10 163.37.56.21 AS 1234 AS 2345 AS 3456 I speak for 172.25.1.0 and 201.32.16.0 Slide 17 Routing How It WorksGovernment Advisory CommitteeJuly 2005 Policy Announcement 172.25.1.4 192.23.9.6 201.32.16.10 163.37.56.21 AS 1234 AS 2345 AS 3456 I prefer AS2345 but not AS3456 Slide 18 Routing How It WorksGovernment Advisory CommitteeJuly 2005 Policy Announcement 172.25.1.4 192.23.9.6 201.32.16.10 163.37.56.21 AS 1234 AS 2345 AS 3456 I refuse AS3456 Slide 19 Routing How It WorksGovernment Advisory CommitteeJuly 2005