In layered systems, PDU represents a unit of data specified in the protocol of a given layer, which consists of protocol control information and user data. PDU is a significant term related to the initial four layers of the OSI model. In Layer 1, PDU is a bit, in Layer 2 it is a frame, in Layer 3 it is a packet and in Layer 4 it is a segment. In Layer 5 and above, PDU is referred to as data.
During Reconstruction, however, the conflict over labor resulted in the sharecropping system, in which black families would rent small plots of land in return for a portion of their crop, to be given to the landowner at the end of each year.nstead of receiving wages for working an ownerâs landâand having to submit to supervision and disciplineâmost freedmen preferred to rent land for a fixed payment rather than receive wages. By the early 1870s, the system known as sharecropping had come to dominate agriculture across the cotton-planting South.
Why did blacks become sharecroppers? Because some people didn't own any land, or they lost their land because they were not able to pay back the money they borrowed, they often became sharecroppers. Emancipatio â¦ n caused a labor shortage on the plantations in the South.