Net1                                                Net2

+---------------+                                   +---------------+
|AR1            |            AR is changed          |AR2            |
+---------------+              ------->             +---------------+
|CPA:           |                                   |CPA:           |
|---------------|                                   |---------------|
|DPA(IPa1):     |                                   |DPA(IPa2):     |
|anchors IP1    |                                   |anchors IP2    |
+---------------+                                   +---------------+

+...............+                                   +---------------+
.MN(IP1)        .              MN moves             |MN(IP2)        |
.flow(IP1,...)  .              =======>             |flow(IP2,...)  |
+...............+                                   +---------------+