How are DDF, ODF and SDH connected? What is the function of DDF?

SDH has a set of circuit boards and a branch circuit board. The group circuit is connected to the optical line ODF through optical fiber jumpers, and is led out through an optical cable welded with the optical line ODF. Or, the group of optical ports are connected to the optical dispatching ODF through optical fiber hopping, docked with the OTU of the wavelength division equipment, and emitted through the wavelength division equipment.

This branch is connected to the optical branch terminal ODF through optical fiber frequency hopping, and connected to the specific service in the future through ODF. The branch electrical interface is connected to DDF through signal cable, and connected to future specific services through DDF.

DDF is a distribution frame, which plays the role of wiring and scheduling physically.

Extended data:

Flights from DDF to DDF:

1, SDH equipment to DDF, such as Huawei SDH transmission equipment OPTIX2500+, since it belongs to DDF, it is of course E 1 service, and the connection with DDF is like this. The service passes through the service processing board PQ 1 to the corresponding E 12S single board as a 2M line (generally called equipment line), and the 2M line is on the DDF side, but DDF is not.

Of course, the single boards of DDF and SDH equipment are also divided into120Ω and 75Ω, which probably means this. ?

2.DDF of jumper transmission equipment between DDF and DDF is generally called DDF out, and DDF of equipment line of switching equipment is called DDF in, so there are several connection modes, namely DDF out.