Network Topologies and Technologies

What is a physical topology?

The arrangement of cabling and how cables connect devices.

What is a logical topology?

The path that data travels between computers.

What is a physical bus topology?

Devices connect along one continuous cable with no central device.

What are four key weaknesses of physical bus topology?

30-device limit, 185 m max cable, termination required, and one break can shut down the network.

Why are terminators used in a bus topology?

They absorb signals and prevent signal bounce/reflection.

What is a physical star topology?

Devices connect individually to a central hub or switch.

What is the main disadvantage of a physical star?

The central device is a single point of failure.

What is an extended star topology?

A star of stars where switches or hubs connect to a central device.

What is a physical ring topology?

Devices form a daisy chain with the last device connected to the first.

What is a point-to-point topology?

A direct physical link between two devices.

What is a point-to-multipoint topology?

A central device communicates with two or more other devices.

What is a mesh topology?

Each device connects to every other device, providing multiple paths.

What is a network backbone?

Cabling that communicates between LANs or hubs/switches.

Which logical topology is used by switched Ethernet?

Switched logical topology.

What physical topology does switched Ethernet commonly use?

Star.

What is UTP?

Unshielded twisted pair; the most common LAN media type.

What is the maximum typical UTP cable length?

100 meters.

What is fiber-optic cabling used for?

Long-distance, high-speed connections, especially between switches and routers.

What is coaxial cable commonly used for today?

Cable Internet access; it is obsolete as a LAN medium.

What is baseband signaling?

Uses the medium's entire bandwidth at a single fixed frequency.

What is broadband signaling?

Uses different frequencies as channels for multiple data streams.

What are Ethernet's major advantages?

Easy installation, scalability, media support, and low cost.

What is an Ethernet frame?

The unit of network information that NICs and switches work with.

What are the three main parts of an Ethernet frame?

14-byte header, 46–1500-byte data field, and 4-byte FCS trailer.

What does CSMA/CD do?

Detects whether the medium is in use and handles detected collisions.

What is a collision?

Two or more devices transmit simultaneously on the same medium.

What is a collision domain?

The extent to which Ethernet signals are propagated.

What does CRC check for?

Whether frame data was altered during transmission.

What is half-duplex communication?

A device can transmit and receive, but not simultaneously.

What is full-duplex communication?

A device can transmit and receive simultaneously.