Singapore occasionally has some quirky routing, i.e. traffic from a client in SG will route via the United States in order to get to a server in SG. E.g.,

Host                                                 Loss%   Snt   Last   Avg  Best  Wrst StDev 
1. sw-sv-10.ofs.edu.sg                                0.0%     6    2.4   2.4   2.3   2.6   0.1 
2. fw1-svcint.ofs.edu.sg                              0.0%     6    0.3   0.3   0.3   0.4   0.0 
3. ofsgw-fe0.ofs.edu.sg                               0.0%     6    0.8   0.9   0.8   1.0   0.1 
4. s5-0-1-8-r10.cyberway.com.sg                       0.0%     6    6.2   4.3   2.5   6.2   1.7 
5. 203.118.7.14                                       0.0%     6    2.5   3.3   2.5   6.8   1.7 
6. 203.118.3.227                                      0.0%     6    7.6   7.1   5.1   9.3   1.5 
7. so-7-0-3.edge3.SanJose1.Level3.net                 0.0%     6  210.4 224.7 209.3 266.9  24.4 
8. ae-22-79.car2.SanJose1.Level3.net                  0.0%     6  209.5 217.1 209.5 238.9  11.3 
   ae-32-89.car2.SanJose1.Level3.net                                                            
   ae-42-99.car2.SanJose1.Level3.net                                                            
   ae-12-69.car2.SanJose1.Level3.net                                                            
9. SINGAPORE-T.car2.SanJose1.Level3.net               0.0%     6  208.9 211.7 208.9 218.1   4.0 
10. ge-5-0-0-0.plapx-cr2.ix.singtel.com                0.0%     6  208.5 209.3 203.7 218.7   6.3
   ge-5-0-0-0.plapx-cr3.ix.singtel.com                                                          
11. so-2-0-3-0.sngtp-cr2.ix.singtel.com                0.0%     6  295.4 296.8 289.7 312.0   8.8
   so-2-0-2-0.sngtp-cr1.ix.singtel.com                                                          
12. ge-1-0-0-0.sngtp-dr2.ix.singtel.com                0.0%     6  284.0 291.4 284.0 302.3   7.6
   ge-0-0-0-0.sngtp-dr2.ix.singtel.com      
13. 202.160.250.230                                    0.0%     6  210.7 213.7 209.2 217.1   3.5                                     
14. 203.208.232.38                                     0.0%     5  215.6 212.4 209.6 216.3   3.3
15. 203.208.232.53                                     0.0%     5  209.3 214.8 209.3 216.4   3.0                                                                                               
16. ae-5-920.sg-br08.eznetsols.com                     0.0%     5  219.0 221.9 212.2 243.5  12.4                    
17. ae-3-7.sg-cr02.eznetsols.com                       0.0%     5  220.1 216.3 213.5 220.1   3.4                                                                          
18. ae-0-17.dr02a.idc1.sg.eznetsols.com                0.0%     5  212.2 216.3 212.2 218.4   2.9
19. re-2-16.ssgw02.idc1.sg.eznetsols.com               0.0%     5  217.8 213.9 211.0 217.8   3.5
20. www.oss.eznetsols.org                              0.0%     5  211.7 214.1 211.5 218.1   3.5

I created a quick shell script client below so that people could help out in the mapping to see how commonly these routing issues occur. It's a short script that grabs the current list of subnets (currently a little over 400) and runs a traceroute to one IP in each netblock. Then it uploads the results to the data directory.

An example run of the script looks like:
$ wget -q http://www.haller.ws/projects/sg-interconnectivity/routing-data-capture.sh 
$ bash routing-data-capture.sh 
found binary '/bin/traceroute'
loading subnets...
mapping connectivity in singapore by largest CIDR...
  58.65.0.0
  58.145.192.0
Thanks for helping out!
Patrick

Index of /projects/sg-interconnectivity/

NameLast ModifiedSizeType
Parent Directory/ -  Directory
data/2009-Aug-26 18:23:46-  Directory
routing-data-capture.sh2009-Aug-24 17:25:361.9Ktext/plain
routing-sg-subnets.txt2009-Aug-24 16:36:185.2Ktext/plain
lighttpd/1.4.28