我可以弄清楚：
1. 3 floors(A, B, C), there is a WIFI AP with same APN but different BSSID in each floor.
2. Will get different IP different subnet if I connect to different WIFI AP
3. the router's MAC address remains same.
其他输出：
A 楼
IP: 10.204.100.12
subnet: 255.255.252.0
router: 10.204.103.254(MAC: for example 11:22:33:44:55:66)
$ traceroute 8.8.8.8
traceroute to 8.8.8.8 (8.8.8.8), 64 hops max, 52 byte packets
1 10.204.1.178 (10.204.1.178) 1.575 ms 1.500 ms 1.517 ms
2 10.204.103.254 (10.204.103.254) 63.216 ms 81.889 ms 9.167 ms
B层
IP: 10.204.109.44
subnet: 255.255.252.0
router: 10.204.111.254(same 11:22:33:44:55:66)
$ traceroute 8.8.8.8
traceroute to 8.8.8.8 (8.8.8.8), 64 hops max, 52 byte packets
1 10.204.1.178 (10.204.1.178) 1.476 ms 1.510 ms 1.465 ms
2 10.204.111.254 (10.204.111.254) 23.543 ms 31.441 ms 19.712 ms
C楼层
IP: 10.204.118.132
subnet: 255.255.252.0
router: 10.204.119.254(same 11:22:33:44:55:66)
$ traceroute 8.8.8.8
traceroute to 8.8.8.8 (8.8.8.8), 64 hops max, 52 byte packets
1 10.204.1.178 (10.204.1.178) 1.743 ms 1.314 ms 1.688 ms
2 10.204.119.254 (10.204.119.254) 43.321 ms 71.116 ms 59.281 ms
所以我想也许是这样？
我不明白的是
1. why router with same MAC address can have different IP?
2. what is 10.204.1.178? this is in different subnet, why I can access it?
3. where might 10.204.1.178 be?
4. any other strange thing?