pengantar teknologi informasi
DESCRIPTION
Pengantar Teknologi Informasi. 7.1. Layer Fisik. Fakultas Ekonomi UNPAR. Sebelumnya. Standard Protocol Layer. Layer Fisik. Sinyal digital dan analog Contoh alat: modem Media transmisi. 1. Layer Fisik: sinyal. Masalah pe-sinyal-an: Sinyal digital Sinyal analog. VOLTAGE LEVEL. - PowerPoint PPT PresentationTRANSCRIPT
Sebelumnya Standard Protocol Layer
OSI LAYER TCP/IPApplication (7) 5. ApplicationPresentation (6)
Session (5)
Transport (4) 4. TransportNetwork (3) 3. InternetData link (2) 2. Data linkPhysical (1) 1. Physical
1. Layer Fisik: sinyal Masalah pe-sinyal-an:
Sinyal digital Sinyal analog
VOLTAGE LEVEL
1 CLOCK CYCLE
1. Layer Fisik Masalah pe-sinyal-an:
Komputer memahami digital (biner) Media ‘hanya’ menghantarkan sinyal
analog
Komputer A
Komputer B
Modem Modem
Sistem Perteleponan
Sinyal digital
Sinyal digital
Sinyal analog
Sinyal analog
1. Modulasi Sinyal dikirimkan dalam
perubahan modus Jenis modulasi:
AM : amplitude FM : frequency PM : phase CM : complex
AM
FM
PM
Carrier
1. Modem Modulator: ubah sinyal digital ke
analog Demodulator: ubah sinyal analog ke
digital (biasa) digunakan menghubungkan
komputer melalui line telepon (analog)
Modem komputer PC
1. Modem Modem:
Modulator - Demodulator Modem komputer PC:
External Internal PCMCIA Port: serial / com, usb, …
Standard: ITU-T
1. Komunikasi Komunikasi: mengirim data dari
sumber ke tujuan. Transmiter: alat untuk mengirim Receiver: alat untuk menerima
DestinationSource
PC 1
transmitter receiver
Destination receiver transmitter Source
PC 2
1. Arah Transmisi Simplex
Contoh: siaran radio
Duplex: Half duplex Full duplex
Pc-1 Pc-2
iBook
trans
mit
recv
Rec
eive
Pc-1 Pc-2
RX
TX
TX
RX
Duplex: full-duplex
simplex
Pc-1 Pc-2
TX
RX
TX
RXmedia
Half duplex
2. Media Transmisi Jenis media
Kabel, wire, guided Nirkabel, wireless, unguided
Karakteristik Topologi Jarak
Kabel Twisted Pair
Shielded twisted pair (stp) Unshielded twisted pair (utp)
Coaxial cable Optical fiber
Hubungan 2 komputer Hubungkan 2 komputer:
serial-to-serial: terminal, null modem network card, UTP cable Network card, coaxial cable
PC-1PC-2
Berbeda: hubungan
komputer dengan external device
(printer, keyboard, …)
Hubungan 2 komputer Hubungkan 2 komputer melalui PSTN
PC-1 PC-2Modem
Modem
USBCOM
Telephone
PSTNPublic Service
TelephoneNetwork
Telephone
Hubungan 2 komputer Hubungkan komputer ke ISP
Internet Service Provider
PC-1Modem
COM
Telephone
PSTNPublic Service
TelephoneNetwork
T1: 32 lines
Rack modem Router
Internet
Twisted Pair Jenis:
STP UTP
Speed autosensing
RJ-45JackRJ-45
Connector
4 pairs (8 lembar)No metal shielding
Fiber Optic Serat lensa
LightSource(LED orLaser)
LightSource(LED orLaser)
Cladding
Core
LightRay
Reflection at Core/Cladding Boundary
Service band service band = pita layanan Setiap service band dibagi
dalam beberapa chanel Bandwidth: lebar pita Makin lebar pita, makin
cepat sinyal Broadband: wide bandwidth Narowband: small
bandwidth
Channel 4
Channel 3
Channel 5
Channel 2
Channel 1
ServiceBand
0 Hz
FrequencySpectrum
(0 Hzto infinity)
Radio Modem Frekuensi radio: 30 – 300
MHz Max data rate: 100 Kbps Jarak tergantung amplifier Radio amatir
waveLAN Standard: 802.11 Unlicensed frequency: 2,4 GHz dan 5,8 GHz
industrial, scientific and medical devices (ISM) Hubungan antar gedung, maks: 5 km; amplifier->60km Digunakan oleh: warnet, sekolah, isp Wired Equivalent Privacy (WEP)
WiFi Wireless Local Area Network based
on IEEE 802.11 specification 802.11b: 11 mbps; 2.4 GHz 802.11g: 50 mbps ; 2.4 GHz 802.11a: 50 mbps; 5 GHz
connecting mobile data devices and Wi-Fi access points to wired network
Wireless Protected Access hotspot
Satellite
Point-to-PointUplink
BroadcastDownlink
Earth Station A
Earth Station B
GeosynchronousSatellite