Show the AS number in traceroute
Passing -a shows you the AS (autonomous system) number:
$ traceroute -a fmi.uni-sofia.bg
traceroute to fmi.uni-sofia.bg (62.44.101.138), 64 hops max, 40 byte packets
1 [AS0] 10.0.0.1 (10.0.0.1) 0.460 ms 0.271 ms 0.256 ms
2 [AS34224] 87.120.206.93.neterra.net (87.120.206.93) 0.871 ms 59.517 ms 1.989 ms
3 [AS5421] border-lozenets.uni-sofia.bg (62.44.96.249) 1.186 ms 1.205 ms 1.342 ms
4 [AS5421] fmi-gw.uni-sofia.bg (62.44.127.15) 1.354 ms 1.669 ms 1.509 ms
5 [AS5421] www.fmi.uni-sofia.bg (62.44.101.138) 1.507 ms 1.698 ms 1.865 ms