  The problem of online packet scheduling to minimize the required conventional
grid energy for transmitting a fixed number of packets given a common deadline
is considered. The total number of packets arriving within the deadline is
known, but the packet arrival times are unknown, and can be arbitrary. The
proposed algorithm tries to finish the transmission of each packet assuming all
future packets are going to arrive at equal time intervals within the left-over
time. The proposed online algorithm is shown to have competitive ratio that is
logarithmic in the number of packet arrivals. The hybrid energy paradigm is
also considered, where in addition to grid energy, energy is also available via
extraction from renewable sources. The objective here is to minimize the grid
energy use. A suitably modified version of the previous algorithm is also shown
to have competitive ratio that is logarithmic in the number of packet arrivals.
