Challenge and Solution Significant dense Packet over SONET (POS) deployments exist despite the overwhelming industry trend toward Ethernet. Operators are looking for POS-like operations, administration, and maintenance (OAM) functions at Ethernet price points with technologies such as OTN G.709 encapsulation. Some operators have traditional transponder systems that can operate only in OC-768 and OTU-3 modes. In addition, bandwidth growth is leading all markets, including data center operators, to move to 40 Gigabit Ethernet in the aggregation layer to handle growth in the data center.