ED1 & ED2 are Equinix Direct uplinks
HE1 & HE2 are Hurricane Electric backup uplinks


        +-----------------------------+         +---------------------------+ 
        |          Router 1           |         |          Router 2         | 
        |                             |         |                           |
        | ge1 ge2 ge3 ge4  ge5   ge6  |         | ge1 ge2 ge3 ge4 ge5  ge6  |
        +--|---|---|---|----|-----|---+         +--|---|---|---|---|----|---+
           |   |            |     |                |   |           |    |
           |   |            |     |                |   |           |    |
           |   |           ED1   HE1               |   |          ED2  HE2
           |   |                                   |   |        
           |   +--------------------------------+  |   |        
            \_                                  |  |   |        
              \_       +------------------------|--+   |        
                \_     |                        |      |        
                  \    |                        |      |        
                   |   |        +-cross-conn-+  |      |        
                   |   |        |            |  |      |        
              +---------------------+      +---------------------+
              |    Switch-1         |      |    Switch-2         |
              |    WS-C3524-XL      |      |    WS-C3524-XL      |
              +---------------------+      +---------------------+
                 |                \_       _/                 |  
                 |                  \_   _/                   |  
                 |                    \_/                     |      
--Cabinets--     |                   _/ \_                    |      
                 |                 _/     \_                  |    
                 |  Cabinet 1    _/         \_   Cabinet n... | 
              +---------------------+      +---------------------+
              |    Switch cab-1     |      |    Switch cab-n     |
              |    WS-C3550-48      |      |    WS-C3550-48      |
              +---------------------+      +---------------------+
                |    |   |     |               |    |    |    |
              host1  |   |     |             host33 |    |    |
                  host2  |     |                 host34  |    |
                       hostn.. |                      hostn.. |
                            host32                         host64

Each cabinet has an uplink to switch-1 and switch-2