  This paper discusses distributed optimization over a directed graph. We begin
with some well known algorithms which achieve consensus among agents including
FROST [1], which possesses the quickest convergence to the optimum. It is a
well known fact FROST has a linear convergence. However FROST works only over
fixed topology of underlying network. Moreover the updates proposed therein
require perfectly synchronized communication among nodes. Hence communication
delays among nodes, which are inevitable in a realistic scenario, preclude the
possibility of implementing FROST in real time. In this paper we introduce a
co-operative control strategy which makes convergence to optimum robust to
communication delays.
