7TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU. Interfaces for the Optical Transport Network[S], ITU T Rec. G.709/Y. 1331, March, 2003.
8ANDREAS GLADISCH. Optics and the Challenge of Carrier Network Transformation [C].Optical Fiber Communication and the National Fiber Optic Engineers Conference, March 2007.
9HUUB VAN HELVROO. Consideration about NG OTN hierarchy[C]. ITU-T, February 2008.
10MAARTEN VISSERS. Analysis of ODU4, ODU2e, ODU0 in G.709 [C].ITU-T, September, 2008.
