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1CSNW1 – week 3 Datacommunicatie. Datacommunicatie?. Datacommunicatie ?. Communications men string telephone wire on an Enewetok tree. National Park Service (USA). Datacommunicatie (1). Multi processor. PU-1. PU-2. MEMORY. I/O. Adresbus databus besturingsbus. Tightly coupled.
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Datacommunicatie? Datacommunicatie ? Communications men string telephone wire on an Enewetok tree. National Park Service (USA)
Datacommunicatie (1) Multi processor PU-1 PU-2 MEMORY I/O Adresbus databus besturingsbus Tightly coupled
Datacommunicatie (2) datacommunicatie kanaal Systeem 1 Systeem 2 loosely coupled, via (extern) netwerk
Communicatiekanaal A B Simplex A B Half-duplex A B Full-duplex
Parallel versus serieel • Bits per second (bps) vs. Bytes per second (Bps) • Baud rate: symbols/sec • bps = baud . 2log n (n: number of signal levels)
Baud rate The number of signaling elements that occur each second. The term is named after J.M.E. Baudot, the inventor of the Baudot telegraph code. bijvoorbeeld 4 niveaus 00 01 10 11 element twee bits bit rate = 2 x baud rate
Multiplexing Multiplexer Demultiplexer
TDM versus FDM Time Division Multiplexing Frequency Division Multiplexing
Shift (transmit) clock Tc Shift register Serial data • Bipolar encoding • Manchester encoding Data buffer Parallel data Clock extracting receiver PLL Serieel (bit-synchroon)
Shift register Serial data Data buffer Parallel data Start bit data bit data bit Par bit Stop bit samples trigger Serieel (asynchroon)
data data ready ready Parallel (strobe) Een strobe is een opgaande of neergaande flank
data REQ ACK Parallel (handshake)
data data ready Ack ready Ack data valid Parallel (handshake)data staat klaar
V.21: 300 bps duplex V.22: 1200 bps duplex V.22bis: 2400 bps duplex V.24: interchange DTE – DCE (RS232) V.32: 9600 bps duplex V32bis: 14.400 bps duplex V.34: 28.800 bps duplex V.90: 56.600 bps duplex X.25: The most popular packet-switching protocol for WANs X.400: The universal protocol for e-mail. V(oiceband) en X - normen ComitéConsultatifInternationalTélégraphiqueetTéléphonique (CCITT) Nu: International TelecommunicationUnion (ITU)
V.24 - RS-232 (25-polig) Recommended Standard => EIA-232-DElectronic Industries Alliance
RI = Ring Indicator 9-polige RS-232 connector
Null Modem DTE DTE Data Terminal Equipment
RS-232 signaal Single-ended
Openbare ‘analoge’ netwerken Spraak 4 kHz bandbreedte (300 - 3400 Hz)
DTE DTE DCE DCE Data Terminal Equipment Data Communication Equipment V24 of RS 232 V21 … V34 Modem (modulator/demodulator)
(Asymmetric) Digital Subscriber Link Splitter Modem Computer
DSL DigitalSubscriberLink 5460 m
ADSL Spectrum Fritz!box Image: Wikipedia
CMTS CableModemTerminationSystem
Opdrachten • Bestudeer hfdst. 10.1 t/m 10.6 • Maak opgaven 10.1 t/m 10.4 en 10.6