| AboveNet,      Inc., a Delaware corporation, directly or indirectly owns 100% of the      ownership interests of each of the following entities: |
|--------------------------------------------------------------------------------------------------------------------------------------------------|
|                                                                                                                                             |   |   |   |
|                                                                                                                                             |   | Jurisdiction |   |
|                                                                                                                                             |   |   |   |
| 1.                                                                                                                                               | AboveNet      Communications, Inc. | U.S. |   |
|                                                                                                                                             |   |   |   |
| 2.                                                                                                                                               | AboveNet      International, Inc. | U.S. |   |
|                                                                                                                                             |   |   |   |
| 3.                                                                                                                                               | AboveNet      Canada, Inc. | Canada |   |
|                                                                                                                                             |   |   |   |
| 4.                                                                                                                                               | AboveNet      of VA, LLC | U.S. |   |
|                                                                                                                                             |   |   |   |
| 5.                                                                                                                                               | AboveNet      of Utah, LLC | U.S. |   |
|                                                                                                                                             |   |   |   |
| 6.                                                                                                                                               | MFN      Japan KK | Japan |   |
|                                                                                                                                             |   |   |   |
| 7.                                                                                                                                               | AboveNet      Communications Europe Limited | U.K. |   |
|                                                                                                                                             |   |   |   |
| 8.                                                                                                                                               | MFN      Europe Finance, Inc. | U.S. |   |
|                                                                                                                                             |   |   |   |
| 9.                                                                                                                                               | MFN      International LLC | U.S. |   |
|                                                                                                                                             |   |   |   |
| 10.                                                                                                                                              | MFN      Europe Limited | U.K. |   |
|                                                                                                                                             |   |   |   |
| 11.                                                                                                                                              | AboveNet      Communications UK Ltd. | U.K. |   |
|                                                                                                                                             |   |   |   |

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