wavelengths to individual optical network units. In addition, the recently standardized
Ethernet OAM capabilities under the IEEE 802.1 ag standard and ITU-T Recommendation Y.
1731, together with state-of-the-art optical timedomain reflectometry provide new link-layer
and physical tools for the effective troubleshooting of WDM-PONs. This article proposes an
integrated troubleshooting box (ITB) for the effective combination of both physical and link …