Pengantar Teknologi Informasi Jaringan (Layer Fisik)
Sebelumnya
Standard Protocol Layer
OSI LAYER
TCP/IP
Application (7)
5. Application
Presentation (6) Session (5)
Transport (4)
4. Transport
Network (3)
3. Internet
Data link (2)
2. Data link
Physical (1)
1. Physical
Layer Fisik Sinyal digital dan analog
1.
2.
Contoh alat: modem
Media transmisi
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 Sistem Perteleponan Modem
Modem
Komputer A Sinyal digital
Sinyal analog
Sinyal analog
Komputer B
Sinyal digital
1. Modulasi
Sinyal dikirimkan dalam perubahan modus Jenis modulasi:
AM : amplitude FM : frequency PM : phase CM : complex
Carrier
AM
FM
PM
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
Source
transmitter
receiver
PC 1
Destination
Destination
PC 2
receiver
transmitter
Source
1. Arah Transmisi Simplex
Pc-2
Pc-1
Contoh: siaran radio
Duplex: full-duplex
Duplex:
RX
Half duplex Full duplex
TX
simplex iBook
TX
Receive
TX
transmit
TX
recv
RX
Pc-1
Pc-2
media RX
RX Half duplex
Pc-1
Pc-2
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
Berbeda: hubungan komputer dengan external device (printer, keyboard, …) PC-1
PC-2
Hubungan 2 komputer
Hubungkan 2 komputer melalui PSTN
Telephone
Telephone
COM
PC-1
USB
Modem
PSTN Public Service Telephone Network
Modem
PC-2
Hubungan 2 komputer
Hubungkan komputer ke ISP
Telephone
Internet
COM
PC-1
Modem
PSTN Public Service Telephone Network
e T1: 32 lin
s
Rack modem
Router
Internet Service Provider
UTP, banyak komputer
1 hub: beberapa komputer jumlah port di hub
Jaringan UTP
Hubungan antar hub
Twisted Pair
Jenis:
STP UTP
4 pairs (8 lembar) No metal shielding
Speed autosensing
RJ-45 Connector
RJ-45 Jack
UTP
Coaxial
cabel TV (CATV) LAN
Fiber Optic
Serat lensa
Cladding Light Source (LED or Laser)
Core Light Ray
Reflection at Core/Cladding Boundary
Wireless
Radio modem waveLAN Access Point WiFi VSAT PAN: bluetooth, IrDA
Service band Frequency Spectrum (0 Hz to infinity)
Channel 5 Channel 4
Service Band
Channel 3 Channel 2 Channel 1 0 Hz
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
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)
Access Point
Penghubung dari wireless ke LAN
Access Point
UTP Switch Or Hub
Server
RJ-45 Port
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
Bluetooth
connecting between mobile data devices PAN: personal area network Frekuensi: 2.4 GHz
IrDA
Infrared Data Association
Satellite Geosynchronous Satellite Point-to-Point Uplink
Broadcast Downlink
Earth Station A
Earth Station B
Topology
Star Bus Ring Bus
Switch, hub, repeater
Jarak
LAN: jarak dekat, area terbatas WAN: jarak jauh, melalui area publik
