Network Redundancy: STP, EtherChannel, and Inter-VLAN Routing

Network Redundancy Technologies

MAC Database Instability

  • If there is more than one path for a frame to be forwarded, an endless loop can result.

Broadcast Storms

  • Switches forward broadcast frames to all ports except the port the broadcast frame first entered.
  • If a Layer 2 loop is formed, broadcast frames are forwarded endlessly, creating a broadcast storm.

Issues with Layer 1 Redundancy: Duplicate Unicast Frames

  • Most upper-layer protocols are not designed to recognize or cope with duplicate transmissions.
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Social Networks, Web 2.0, Telecoms, and Mobile Technology

Social Networks and Web 2.0

A social network is a community of people related by some kind of interest, affinity, or anything else they have in common.

Web 2.0 is a set of sites where the user is not a mere recipient of content but participates in its development and diffusion.

Telecommunications Fundamentals

Telecoms: Media broadcasting, transmitting, and receiving messages using electrical or electromagnetic signals.

Components of a telecommunication system: Transmitter, transmission channel, and receiver.

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Ethernet Network Fundamentals and Operations

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Refer to the Exhibit: Full-Duplex Operation

Refer to the exhibit. The switch and workstation are administratively configured for full-duplex operation. Which of the following statements accurately reflects the operation of this link?

There will be no collisions in this type of link.

Random Delay in Ethernet Collisions

Why does a host on an Ethernet segment that experiences a collision use a random delay before attempting to transmit a frame?

A random delay helps prevent the stations from experiencing

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Understanding Computer Networks: LAN, WAN, Topologies & Protocols

Understanding Computer Networks

Network Types

  • LAN (Local Area Network): Limited geographically, greater capacity, higher transmission speeds, lower error rate.
  • WAN (Wide Area Network): Wide geographical area, lower capacity, higher error rate.

Other Network Types

  • Metropolitan (MAN)
  • Personal Area (PAN)
  • Wireless LAN (WLAN)

MAN (Metropolitan Area Network)

Limited to areas like a city population.

PAN (Personal Area Network)

Home networks are simple and small, using wireless or cable connections, with small costs.

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Circuit Switching, Virtual Circuits, and Multiplexing Techniques

A circuit-switched network is made of a set of switches connected by physical links, in which each link is divided into n channels. Figure 8.3 illustrates a trivial circuit-switched network. In circuit switching, resources need to be reserved during the setup phase; the resources remain dedicated for the entire duration of data transfer until the teardown phase. 

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Virtual-Circuit Networks

A virtual-circuit network is a cross between a circuit-switched network and a datagram network, exhibiting characteristics

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Networking Essentials: Dial-Up, Servers, and Active Directory

Networking Essentials

Dial-Up Networking Parameters

The necessary parameters include transmission lines, communication power, and telephone terminals.

SMTP Server Explained

An SMTP (Simple Mail Transfer Protocol) server is responsible for transferring email between different servers and moving messages from clients to servers.

PPTP Server Defined

PPTP (Point-to-Point Tunneling Protocol) encapsulates packets from local area networks, making them transparent to the network procedures used in data transmission

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