Have you checked that you have matched the physical media framing - e.g., LAN PHY needs to speak to LAN PHY (or WAN PHY to WAN PHY). Typically the ONS 15454 would be looking for a SONET frames (WAN PHY) while a Cisco 6509 would be sending 10 Gigabit Ethernet LAN frames (LAN PHY). That is, unless you specifically choose an interface for your 6509 such as the XENPAK-10GB-LW (10GBASE-LW XENPAK Module with WAN PHY for SMF). From that product's data sheet: "The Cisco 10GBASE-LW Module supports a link length of 10 kilometers on standard single-mode fiber (SMF) (G.652).
WAN-PHY is intended to allow the transport of 10 Gigabit Ethernet over a traditional SONET/SDH infrastructure. The purpose of WAN-PHY is to render 10 Gigabit Ethernet compatible with SONET STS-192c format and data rate, as defined by ANSI, as well as the SDH VC-4-64c container specified by ITU."
One can also use Cisco ONS transponder cards that will wrap LAN PHY framing in something like G.709 encapsulation to allow it to be transported through a DWDM network.
