  This paper puts forth a multi-stream networking paradigm, referred to as
soft-source-information-combining (SSIC), to support wireless Internet of
Things (IoT) applications with ultra-reliability requirements. For SSIC
networking, an SSIC dispatcher at the source dispatches duplicates of packets
over multiple streams, which may be established over different physical
wireless networks. If a packet on a stream cannot be decoded due to wireless
interference or noise, the decoder makes available the packet's soft
information. An aggregator then combines the soft information of the duplicates
to boost reliability. Of importance are two challenges: i) how to descramble
the scrambled soft information from different streams to enable correct SSIC;
ii) the construct of an SSIC dispatching and aggregation framework compatible
with commercial network interface cards (NICs) and TCP/IP networks. To address
the challenges, we put forth: i) a soft descrambling (SD) method to minimize
the bit-error rate (BER) and packet-error rate (PER) at the SSIC's output; ii)
an SSIC networking architecture readily deployable over today's TCP/IP networks
without specialized NICs. For concept proving and experimentation, we realized
an SSIC system over two Wi-Fi's physical paths in such a way that all legacy
TCP/IP applications can enjoy the reliability brought forth by SSIC without
modification. Experiments over our testbed corroborate the effectiveness of
SSIC in lowering the packet delivery failure rate and the possibility of SSIC
in providing 99.99% reliable packet delivery for short-range communication.
