Using Mobile Metrics to Drive Network Analysis on Android Devices Bo Yan Department of Computer Science University of Massachusetts Lowell Network Analysis An important research topic as many communicate via mobile devices Troubleshoot network connectivity Diagnose network performance Bo Yan Department of Computer Science, University of Massachusetts Lowell What Kind Of Metrics Do We Have Network metrics Signal strength Connection states Latency and bandwidth Context information Location Geo-coordinates Cell tower User Behavior Indoor/outdoor Still/moving Bo Yan Department of Computer Science, University of Massachusetts Lowell Signal Strength Signal Strength dBm (or dBmW) is an abbreviation for the power ratio in decibels (dB) of the measured power referenced to one milliwatt (mW) X = 10 * log10P + 30 expresses an arbitrary power P as x dBm Bo Yan Department of Computer Science, University of Massachusetts Lowell Cellular Signal Strength - GSM GSM signal ASU (Active Set Update) An integer value proportional to the received signal strength In range from 0 to 30, and 99, defined in 3GPP TS 27.007 8.5 Signal[dBm] = -113 + 2 * Signal[asu] GSM Bit Error Rate In range from 0 to 7, and 99, defined in 3GPP TS 27.007 8.5 RXQUAL_0, BER < 0.2% RXQUAL_1, 0.2% < BER < 0.4% RXQUAL_2, 0.4% < BER < 0.8% RXQUAL_3, 0.8% < BER < 1.6% RXQUAL_4, 1.6% < BER < 3.2% RXQUAL_5, 3.2% < BER < 6.4% RXQUAL_6, 6.4% < BER < 12.8% RXQUAL_7, 12.8% < BER Bo Yan Department of Computer Science, University of Massachusetts Lowell Cellular Signal Strength - CDMA CDMA RSSI (Received Signal Strength Indication) Value in dBm CDMA EC/IO Value in dB * 10 The ratio of received pilot energy, Ec, to total received energy, Io. Ec/Io[dB] = RSSI[dBm] – RSCP[dBm] EVDO RSSI Value in dBm EVDO Ec/Io Value in dB * 10 EVDO SNR (Signal to Noise Ratio) Value in range from 0 to 8 SNR[dB] = RSSI[dBm] – NOISE[dBm] Bo Yan Department of Computer Science, University of Massachusetts Lowell Cellular Network States Call states IDLE, RINGING, OFFHOOK Incoming phone number Data activity IN, OUT, INOUT, DORMANT Data connection states DISCONNECTED, CONNECTING, CONNECTED, SUSPEND Bo Yan Department of Computer Science, University of Massachusetts Lowell Wi-Fi Network States Wi-Fi supplicant states ASSOCIATED, ASSOCIATING, AUTHENTICATING, COMPLETED, DISCONNECTED, DORMANT, FOUR_WAY_HANDSHAKE, GROUP_HANDSHAKE, INACTIVE, INTERFACE_DISABLED, INVALID, SCANNING, UNINITIALIZED Access Point SSID and BSSID link speed Bo Yan Department of Computer Science, University of Massachusetts Lowell Network Performance Network Latency Ping command result Socket connection latency Network Goodput Ping command result Upload/download test to/from a target server Bo Yan Department of Computer Science, University of Massachusetts Lowell Location Geo-coordinates Latitude and longitude Help identify dead zone Cell tower Report weak signal coverage Bo Yan Department of Computer Science, University of Massachusetts Lowell User Behavior Accelerometer Sensor Infer movement from 3D accelerations Light Sensor Day time or mid night Bo Yan Department of Computer Science, University of Massachusetts Lowell Example – Troubleshoot Network Connectivity PHONE TYPE GSM CDMA SIM CARD READY DATA ENABLED YES YES AIRPLANE MODE NO REPLACED BY WI-FI NO CELLULAR SIGNAL YES SUPPLICANT STATE CONNECTED WI-FI SIGNAL Bo Yan Department of Computer Science, University of Massachusetts Lowell Example – Network Latency LATENCY TO WEBSITE ABNORMAL LATENCY TO CARRIER NORMAL PACKET DROP HEAVY CELLULAR SIGNAL ABNORMAL LATENCY TO INTERNET Bo Yan Department of Computer Science, University of Massachusetts Lowell