The role of traffic forecasting in QoS routing - a case study of time-dependent routing

QoS routing solutions can be classified into two categories, state-dependent and time-dependent, according to their awareness of the future traffic demand in the network. Compared with representative state-dependent routing algorithms, a time-dependent variation of WSP - TDWSP - is proposed in this paper to study the role of traffic forecasting in QoS routing, by customizing itself for a range of traffic demands. Our simulation results confirm the feasibility of traffic forecasting in the context of QoS routing, which empowers TDWSP to achieve better routing performance and to overcome QoS routing difficulties, even though completely accurate traffic prediction is not required. The case study involving TDWSP further reveals that even a static forecast can remain effective over a large area in the solvable traffic demand space, if the network topology and the peak traffic value are given. Thus, the role of traffic forecasting in QoS routing becomes more prominent.