This paper proposes a new type of buffer management mechanisms

called"Additional Buffer Block Allocation on demand"(ABBA) scheme

suited for packet switches and routers.With the essntial of the proposed mechanism presented

we establish the associated queuing model

denoted by "M/M/1/K(2K)"

and then derive the steady-state probability distribution and related packet loss probability.By both analysis and simulations

we evaluate the performance of the proposed ABBA scheme in terms of the packet loss probability and the equivalent buffer size K

e

in comparison with typical schemes with static buffer allocation.Finally provided in this paper are some key factors used to determine whether an additional-buffer-block application is approved or not by a decision-making process

which is described in an algorithm form.