  The realization of an elementary quantum network that is intrinsically secure
and operates over long distances requires the interconnection of several
quantum modules performing different tasks. In this work we report the
interconnection of four different quantum modules: (i) a random polarization
qubit generator, (ii) a free-space quantum communication channel, (iii) an
ultra-low noise portable quantum memory and (iv) a qubit decoder, in a
functional elementary quantum network possessing all capabilities needed for
quantum information distribution protocols. We create weak coherent pulses at
the single photon level encoding polarization states $|H\rangle, |V\rangle,
|D\rangle, |A\rangle$ in a randomized sequence. The random qubits are sent over
a free-space link and coupled into a dual rail room temperature quantum memory
and after storage and retrieval are analyzed in a four detector polarization
analysis akin to the requirements of the BB84 protocol. We also show ultra-low
noise and fully-portable operation, paving the way towards memory assisted
all-environment free space quantum cryptographic networks.
