There's a website I've been going to for a while that may interest a few called http://www.cidr-report.org

It's basically a report generated on the state of the internet from the perspective of either AS4777 (APNIC - the Asia Pacfic Network Information Centre - the RIR for Australia) or AS6447 (The University of Oregon Route Views Project). Some interesting things to note:

There are over 300 000 prefixes sitting in the memory of every internet router.
This could be improved by ~38% if ISP's aggregated their routes properly (Some ISP's could improve their efficiency by over 90%)
The largest ISP in terms of prefixes advertised is TW Telecom in the USA which advertises 4312 prefixes (as 17 August 09) and could reduce that to 1710 with proper aggregation (60% improvement)

You can also complete an AS search which will give all sorts of information including a WHOIS on the owner, prefix information, the AS_Path from the report agent, and any upstream/downstream AS' from the report agent.

Some AS' of interest:

AS1221 ASN-TELSTRA Telstra Pty Ltd
AS109 CISCO-EU-109 Cisco Systems Global
AS15169 GOOGLE - Google Inc.

So for an example, my ISP at home is Beagle, which buys from ISP One Wholesale which buys from Telstra Internet Direct. ISP One advertises the prefixes (guessing Beagle is too small for their own AS!)

Prefix AS Path
121.79.0.0/18 4608 17819 23702
121.79.64.0/19 4608 17819 23702
124.254.64.0/18 4608 17819 23702
124.254.96.0/20 4608 1221 23702

So that tells us that to get from APNIC to my place, it travels from 4608 (APNIC) through either 17819 (Equinix Asia Pacific) or 1221 (Telstra) to 23702 (ISPOne). So logically, any traceroute I perform at home will pass through those two ISP's.

From APNIC's view of the internet, Telstra and Equinix are considered upstream from ISP One. Given that ISP One has no downstream AS's, we can conclude that they aren't providing hosting to any large organisations. We can also conclude that ISP One is a dual-homed non-transit (probably) system. So where do my little packets go from here? It's difficult to say.

If you observe the upstream/downstream lists of Telstra and Equinix, it gives you an idea of what systems are used by those ISPs to traverse the rest of the internet, for example in the case of Equinix:

Upstream Adjacent AS list
AS4635 HKIX-RS1 Hong Kong Internet Exchange--Route Server 1
AS4608 APNIC-AP Asia Pacific Network Information Center, Pty. Ltd.
AS10026 ANC Asia Netcom Corporation
AS2516 KDDI KDDI CORPORATION
AS1221 ASN-TELSTRA Telstra Pty Ltd
AS24114 ASN-EQIX-SGW-EE-AP Equinix Asia Pacific
AS4637 REACH Reach Network Border AS
AS4725 ODN SOFTBANK TELECOM Corp.

So we can begin to draw a map of the internet



Understatement of the century - it's much more complicated then that, I've only drawn a very cut down map and I'm not sure I even got all the links between the AS' concerned.

Amazing what you can come up with at 3am.

So what determines the paths that traffic takes? BGP.

Well as it turns out, my map isn't entirely accurate but I have a good excuse

C:\>tracert http://www.youtube.com

Tracing route to youtube-ui.l.google.com [66.249.89.100]
over a maximum of 30 hops:

1 <1 ms <1 ms <1 ms 192.168.2.254
2 33 ms 37 ms 27 ms lns03.ispone.net.au [124.254.72.20]
3 27 ms 26 ms 27 ms lns.gw.ispone.net.au [124.254.72.129]
4 * 43 ms 41 ms as42.sydney.pipenetworks.com [218.100.2.98]
5 42 ms 41 ms 40 ms 66.249.95.226
6 160 ms 154 ms 153 ms 66.249.95.134
7 191 ms 156 ms 155 ms 209.85.255.57
8 169 ms 166 ms 158 ms 72.14.236.126
9 158 ms 156 ms 155 ms nrt04s01-in-f100.google.com [66.249.89.100]

That trace route reveals ISP One and Google have a peer connection with Pipe Networks which didn't show up under CIDR-Report. However, some research into Pipe Networks shows that they actually have a separate AS for each POP:

AS9722 PIPE-AS-AP PIPE Networks
AS9894 PIPE-CANB-AS PIPE Networks Canberra Internet Exchange.
AS17999 PIPE-ADE-AS-AP PIPE Networks Adelaide Internet Exchange.
AS18398 PIPE-SYD-AS PIPE Networks Sydney Internet Exchange.
AS23741 PIPE-HBT-AS PIPE Networks Hobart Internet Exchange.
AS23745 PIPE-MEL-AS PIPE Networks Melbourne Internet Exchange.
AS37987 PIPE-IX7-AS PIPE Networks
AS38046 PIPE-IX8-AS PIPE Networks

For some reason, most of the AS' hanging off these aren't listed, but if you check the Pipe Networks website you see that both Google and ISP One peer with Pipe in NSW.

very interesting reading, just a tad above me but interesting none the less. Keep it coming