Posts Tagged ‘stp’
July 28th, 2008 | 
Author: Physical Layer Protocols and Services:
L1 controls how data is placed on the media.
It has to encode bits into signals and Tx/Rx these signals across the physical media.
The delivery of frames across media requires.
Physical media and connectors.
A representation of bits – code.
Encoding of data and control information.
Tx and Rx circuitry on devices.
The purpose of L1 is to create the electrical, optical, or radio signal that reqresents the bits in each frame.
It also must retrieve signals from media, restore them to bit representations, and pass them to L2 as a complete frame.
The type of signal – depends on the type of media.
Copper = electrical pulses.
Fiber = patterns of light.
Wireless = patterns of radio transmissions.
Tags: wan, 802.1q, guides, cisco, vlan, router
Bitmindframes Study guides
Spanning Tree Protocol & Layer 2 Redundency.
Layer 2 redundency improves network availability with alternative network paths.
A simple path can be disrupted with little impact.
Redundency is achieved at the distribution & core through additional hardware & alternate paths.
Each Access Layer switch is connected to 2 different Distribution Layer switches.
Each Distribution Layer switch is connected to 2 Core Layer switches.
Spanning Tree Protocol is enabled by default.
Spanning Tree Protocol puts some ports into forwarding & others in blocking.
This prevents Layer 2 switching loops. Spanning Tree Protocol uses a redundant link if the primary fails.
Tags: vtp, cisco, switch, router, ip, guides