This series is commonly known as the ping-pong effect:
12 21 ms 22 ms 21 ms bb2-p6-0.dllstx.sbcglobal.net [151.164.240.226] 13 20 ms 21 ms 27 ms ex2-p2-0.eqdltx.sbcglobal.net [151.164.240.225] 14 21 ms 24 ms 23 ms bb2-p6-0.dllstx.sbcglobal.net [151.164.240.226] 15 32 ms 21 ms 23 ms ex2-p2-0.eqdltx.sbcglobal.net [151.164.240.225] 16 22 ms 24 ms 22 ms bb2-p6-0.dllstx.sbcglobal.net [151.164.240.226] 17 23 ms 21 ms 24 ms ex2-p2-0.eqdltx.sbcglobal.net [151.164.240.225] 18 23 ms 24 ms 22 ms bb2-p6-0.dllstx.sbcglobal.net [151.164.240.226] 19 27 ms 22 ms 23 ms ex2-p2-0.eqdltx.sbcglobal.net [151.164.240.225] 20 23 ms 23 ms 27 ms bb2-p6-0.dllstx.sbcglobal.net [151.164.240.226] 21 25 ms 42 ms 24 ms ex2-p2-0.eqdltx.sbcglobal.net [151.164.240.225] 22 23 ms 38 ms 24 ms bb2-p6-0.dllstx.sbcglobal.net [151.164.240.226] 23 25 ms 23 ms 30 ms ex2-p2-0.eqdltx.sbcglobal.net [151.164.240.225]