Barclays networking equipment analyst Jeff Kvaal raises ratings on Polycom (PLCM +5.9%) and Shoretel (SHOR +4.9%), while lowering Riverbed (RVBD -3.4%). Healthy trends in videoconferencing and unified communications should allow PLCM and SHOR to lead networking peers, he writes, but demand for Riverbed may be slower to recover in a downturn.