  In $k$-ported message-passing systems, a processor can simultaneously receive
$k$ different messages from $k$ other processors, and send $k$ different
messages to $k$ other processors that may or may not be different from the
processors from which messages are received. Modern clustered systems may not
have such capabilities. Instead, compute nodes consisting of $n$ processors can
simultaneously send and receive $k$ messages from other nodes, by letting $k$
processors on the nodes concurrently send and receive at most one message. We
pose the question of how to design good algorithms for this $k$-lane model,
possibly by adapting algorithms devised for the traditional $k$-ported model.
We discuss and compare a number of (non-optimal) $k$-lane algorithms for the
broadcast, scatter and alltoall collective operations (as found in, e.g., MPI),
and experimentally evaluate these on a small $36\times 32$-node cluster with a
dual OmniPath network (corresponding to $k=2$). Results are preliminary.
