Download Introduction to Mobile Systems

By:
Seyed Mohammad Makki
In :
Mofid High School
LAN and Ethernet
Global network and Internet
Internet Service Providers (ISPs)
Hosts: Servers and Clients
Transmission Control Protocol (TCP)
Internet Protocol (IP)
What is a protocol?
Access Networks
 Dial up
 DSL (Digital Subscriber Line)
 Cable
 FTTH (Fiber to the Home)
 Ethernet
 WiFi (Wireless LAN)
 Wide Area Wireless Access
 WiMAX
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Physical Media
 Twisted Pair Copper Wire
 Coaxial Cable
 Fiber Optics
 Terrestrial Radio Channels
 Satellite Radio Channels
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Circuit Switching & Packet
Switching
 Differences
 Advantages of Packet Switching
 Disadvantages of packet switching:
 Delay
 Loss
 Throughput
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Architecture of computer networks
 Layered architecture
1. Application Layer
2. Transport Layer
3. Network Layer
4. Link Layer
5. Physical Layer
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Networks Under Attack
 Attack to different layers
 Security of networks
 firewall
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Application Layer Protocols
 WEB and HTTP (Hyper Text Transfer Protocol)
 Cookies
 Proxy Server or Web Caching
 FTP (File Transfer Protocol)
 SMTP (Simple Mail Transfer Protocol)
 DNS (Domain Name System)
 Socket Programming
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Transport Layer
 TCP vs. UDP
 Transmission Control Protocol
 User Datagram Protocol
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The Network Layer
 What is inside a router?
1.
2.
3.
4.
Input ports
Output ports
Switching fabric
Routing processor
 Routing algorithms
 Differences between hub & router
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The Link Layer & LAN
 Different kinds of detection and correction codes such
as:
 Error detection & correction codes
 Parity checks
 Cyclic Redundancy Check (CRC)
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Wireless and Mobile Networks
 Elements of wireless networks:
1. Wireless hosts
2. Wireless links
3. Base station
 Mobility and Doppler effect
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Differences of Wired & Wireless
Links
Decreasing signal strength (path loss)
2. Interference from other sources
3. Multipath propagation (fading in mobiles)
1.
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WiFi:802.11 Wireless LANs
 Mobility in the same IP subnet
 Power management
 Bluetooth
 WiMax
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Bluetooth
 Less than 100 meters
 2.4 GHz
 TDM with time slots of 625 microseconds
 79 channels
 FHSS (Frequency Hopping Spread Spectrum)
 Data rate: 4 Mbps
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WiMAX
 Interoperability for Microwave Access
 FDM
 Power management
 Hand off
 QoS support
 security
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Cellular Internet Access
 GSM (Global System for Mobile Communications)
 200 KHz frequency bands
 Each band supporting 8 TDM calls
 Speech encoding rate : 13 kbps
 CDMA
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Thank you !
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