Transcript Mobile.Network.Data - Computer Science
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 * log 10 P + 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
CDMA
DATA ENABLED
YES GSM
AIRPLANE MODE
NO
REPLACED BY WI-FI
NO YES
CELLULAR SIGNAL SIM CARD READY
YES
SUPPLICANT STATE
CONNECTED
WI-FI SIGNAL
Bo Yan Department of Computer Science, University of Massachusetts Lowell
Example – Network Latency
LATENCY TO WEBSITE
ABNORMAL NORMAL
LATENCY TO CARRIER
ABNORMAL
LATENCY TO INTERNET PACKET DROP
HEAVY
CELLULAR SIGNAL
Bo Yan Department of Computer Science, University of Massachusetts Lowell