Osi physical layer
1 / 10

OSI Physical Layer - PowerPoint PPT Presentation

  • Uploaded on

OSI Physical Layer. Network Fundamentals – Chapter 8. Fiber Media. Copper uses electrical voltage to represent data. Fiber-optic cable uses light pulses conducted through special glass conductors to carry data .

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about ' OSI Physical Layer' - wylie

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Osi physical layer

OSI Physical Layer

Network Fundamentals – Chapter 8

Fiber media
Fiber Media

  • Copper uses electrical voltage to represent data.

  • Fiber-optic cable uses light pulses conducted through special glass conductors to carry data.

  • Fiber has greater bandwidth and can run much farther than cable without needing a signal enhanced,

  • but the higher cost of fiber-optic cable and connectors, + special training required for installing + handling fiber.

Fiber media1
Fiber Media

  • Because fiber does not carry voltage and current = immune to the earth ground and lightning concerns.

  • Usually considered the best choice for backbone connections between floors and wiring closets in large buildings and for connections between buildings on a campus.

Fiber media2
Fiber Media

  • Fiber-optic cable starts with a core strand of glass or special plastic on which the light signal travels.

  • Around the glass is cladding, a special material that reflects escaping light into the core.

  • Outer layers protect and strengthen the vulnerable center core from moisture and damage.

Fiber media3
Fiber Media

  • There are two basic types of fiber-optic cable:

    • single-mode - most commonly used by telephone companies and in data installations as backbone cable.

    • multimode - usually the fiber-optic cable used with networking applications such as FDDI and ATM

Wireless media
Wireless Media

  • Wireless media carry electromagnetic radio signals that represent the binary data of the data-link frame.

  • Transmit and receive signals through the medium of the open atmosphere = open areas are best

  • Within buildings, interference occurs from physical objects such as

    • walls, metal air ducts,

    • and floors and

    • machinery.

    • + subject to degradation

    • microwave ovens,

    • fluorescent lighting,

    • phones and Bluetooth devices.

Wireless media1
Wireless Media

  • Four common data communications standards that apply to wireless media:

    • ■ Standard IEEE 802.11: Commonly referred to as Wi-Fi, 802.11 is a wireless LAN (WLAN) technology that uses a contention or nondeterministic system with a carrier sense multiple access/collision avoid (CSMA/CA) media access process.

    • ■ Standard IEEE 802.15:Wireless Personal-Area Network (WPAN): Commonly known as Bluetooth, 802.15 uses a device-pairing process to communicate over distances from 1 to 100 meters.

    • ■ Standard IEEE 802.16: Commonly known as WiMAX (Worldwide Interoperability for Microwave Access), 802.16 uses a point-to-multipoint topology to provide wireless broadband access.

    • ■ Global System for Mobile Communication (GSM): Includes physical layer specifications that enable the implementation of the Layer 2 General Packet Radio Service (GPRS) protocol to provide data transfer over mobile cellular telephony networks.