一直觉得联通的出口不错， traceroute 了一下日本的 ip，这样应该是直连吧？

traceroute: Warning: www.yahoo.co.jp has multiple addresses; using 183.79.139.228
traceroute to www.g.yahoo.co.jp (183.79.139.228), 64 hops max, 52 byte packets
router.asus.com (192.168.1.1) 0.608 ms 0.243 ms 0.147 ms
183.94.220.1 (183.94.220.1) 2.033 ms 3.580 ms 1.803 ms
58.19.113.193 (58.19.113.193) 2.407 ms 5.408 ms 3.413 ms
58.19.112.13 (58.19.112.13) 4.310 ms 1.961 ms 1.856 ms
219.158.22.77 (219.158.22.77) 26.220 ms
219.158.22.73 (219.158.22.73) 27.531 ms 25.342 ms
219.158.12.97 (219.158.12.97) 21.800 ms 20.251 ms 19.744 ms
219.158.97.190 (219.158.97.190) 34.760 ms 37.760 ms 37.170 ms
219.158.98.78 (中国 联通骨干网) 90.686 ms 92.273 ms 91.041 ms
softbank221111202069.bbtec.net (221.111.202.69) 82.995 ms 87.979 ms 86.196 ms
* * *
61.206.157.74 (61.206.157.74) 92.907 ms 86.221 ms 83.648 ms
124.83.252.242 (124.83.252.242) 79.516 ms 77.513 ms 80.441 ms
* * *