| 摘要 |
An optical line terminal OLT monitors and controls communications with plurality of optical nodes ONs, such as optical network units ONUs and/or optical network terminators ONTs, with in a passive optical network PON, such as, but not exclusively, an Ethernet-based passive optical node EPON. A tagging mechanism is implemented to identify an origin ON that introduces a frame into the PON segment linking the origin ON with the OLT. The origin ON produces a PON tag to associate its identifier ON_ID to the frame. The PON tag facilitates filtering and forwarding operations, and enables the physical layer interface PHY to the PON segment to emulate a point-to-point and/or shared communications link. The PON tag allows a MAC control layer to create the virtual ports to traffic incoming and outgoing optical signals, and supply the virtual ports to a forwarding entity for frame filtering and forwarding. The PON tag also allows an OLT and ON to track the origination and/or destination of a frame with the PON segment, and accept pr reject the frame based on the contents of the PON tag. |
