>What is the source for traceroute when doing AS lookups ? I encountered this:

well...you could look at the source.  :)

>$ traceroute -a 193.226.59.5
>traceroute to 193.226.59.5 (193.226.59.5), 64 hops max, 40 byte packets
> 1  [AS8708] bucharest-nas1.rdsnet.ro (193.231.236.29)  160.839 ms  131.063 
>ms  118.255 ms
> 2  [AS8708] 213.157.165.254 (213.157.165.254)  120.081 ms  123.123 ms  
>117.842 ms
> 3  [AS8708] 212.93.128.6 (212.93.128.6)  130.799 ms  119.435 ms  126.253 ms
> 4  [AS11042] kefren.netbsd.ro (193.226.59.5)  137.480 ms  117.403 ms  
>126.743 ms

it uses rpsl to talk to whois.radb.net.  whois.radb.net returns three
answers for the origin of 193.226.59.5/32: AS11042, AS8708, AS11042.
traceroute prints the first one.  arguably, in the case of multiple
returns, it ought to pick the most specific one in the case of varying
block sizes (which it doesn't do), but in this case that wouldn't
matter because the blocks are all /24.  hmm...perhaps it should pick
the most recent answer...even though that's also definitely wrong at
times.

>$ whois -h whois.ripe.net -r 193.226.59.5/32

% whois -h whois.radb.net -r 193.226.59.5/32
route:         193.226.59.0/24
descr:         Frontier GlobalCenter Customer Subnet 193.226.59.0/24
origin:        AS11042
mnt-by:        MAINT-AS3549
changed:       who@globalcenter.net 19980825
source:        RADB

route:        193.226.59.0/24
descr:        ROMTELENET
origin:       AS8708
mnt-by:       AS8708-MNT
changed:      tim@rdsnet.ro 20010918
source:       RIPE

route:        193.226.59.0/24
descr:        Frontier GlobalCenter Customer Subnet 193.226.59.0/24
origin:       AS11042
mnt-by:       PRIMENET-MAINT-MCI
changed:      who@globalcenter.net 19980824
source:       CW

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