Poster Abstract: Security in Uplink MU-MIMO Networks

Multiple-In-Multiple-Out (MIMO) o‚ffers great potential for increasing network capacity by exploiting spatial diversity with multiple antennas. Multiuser MIMO (MU-MIMO) further enables Access Points (APs) with multiple antennas to transmit multiple data streams concurrently to several clients. However, the uplink data transmission (from client to AP) of MU-MIMO is more vulnerable because its wide distribution and diversi€cation. We explore the vulnerability in clients’ feedback of estimated CSI to the AP. We then propose two aŠacks potentially taken by malicious clients and malicious AP respectively: (1) the forging client aŠack that malicious client report the forged CSI to the AP and (2) forging AP aŠttack that malicious AP transmits wrong training frame to clients. Both of these aŠacks can lead to incorrect resolving at AP and ruin the whole uplink communication. Correspondingly, we design countermeasures for these aŠacks, namely CVU and CFU. We evaluate their performance via simulators. Based on our experimental results, we suggest a new CSI feedback scheme to prevent CSI forging, which only requires slight modi€cation at the client side and easy for deployment.