The packet dropping algorithm drops the QoE-marked priority packets before they are fed into the scheduler.
The dropping algorithm in [18] computes average achievable bitrate of each user by considering the downlink channel quality.
The function of the packet dropping algorithm is to shape the traffic according to the wireless transmission capacity, whereas the function of the scheduler is to perform packet scheduling onto the radio resources.
The default in TBLASTN is to use the x-drop algorithm, and we use the x-drop algorithm in the tests presented in this paper.
If the x-drop algorithm is applied, the composition is computed individually for each HSP that is realigned.
To avoid needlessly computing the full dynamic programming matrix, we added functionality similar to the original x-drop algorithm (Altschul et al., 1990).
The following pseudocode shows how alignments corresponding to a single query-subject match are recomputed when the x-drop algorithm is used.
By default, the x-drop algorithm [ 2, 49] is applied to a set of starting points specified in the lists of HSPs provided from previous stages of the BLAST algorithm[ 1, 2].
Furthermore, it offers a sensitive version of the x-drop algorithm for seed-extension, which results in highly accurate alignments compared with the BLAST gold standard and our competitors.
The x-drop algorithm requires a starting point (p q, p s ) that will force an alignment between offset p q in the query and p s in the subject.
In the following sections, we consider three categories of algorithms: work-conserving scheduling-based algorithms (Section 4.1), preferential packet-drop algorithms (Section 4.2), and traffic-shaping algorithms (Section 4.3).
