  We consider the age of information in a multicast network where there is a
single source node that sends time-sensitive updates to $n$ receiver nodes.
Each status update is one of two kinds: type I or type II. To study the age of
information experienced by the receiver nodes for both types of updates, we
consider two cases: update streams are generated by the source node at-will and
update streams arrive exogenously to the source node. We show that using an
earliest $k_1$ and $k_2$ transmission scheme for type I and type II updates,
respectively, the age of information of both update streams at the receiver
nodes can be made a constant independent of $n$. In particular, the source node
transmits each type I update packet to the earliest $k_1$ and each type II
update packet to the earliest $k_2$ of $n$ receiver nodes. We determine the
optimum $k_1$ and $k_2$ stopping thresholds for arbitrary shifted exponential
link delays to individually and jointly minimize the average age of both update
streams and characterize the pareto optimal curve for the two ages.
