| Light-Hierarchy: The Optimal Structure for Multicast Routing in WDM Mesh Networks Recent countries visiting this post |  |
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| Light-Hierarchy: The Optimal Structure for Multicast Routing in WDM Mesh Networks Recent countries visiting this post | |
| 5 | United States |
| 3 | Russian Federation |
| 1 | |
| 1 | Turkey |
| 1 | China |
| 1 | Japan |