Module 6.2 - Physical and Logical Topologies Flashcards
2 types of topology
Physical and logical topology
physical topology
Identifies the physical connections and how end devices and intermediary devices are interconnected.
Logical Topology
Identifies virtual connections using device interfaces and layer 3 IP addressing schemes
it influences the type of network framing and media access control used
Logical Topology
most common WAN topology
point-to-point
Hub and spoke
Interconnects branch sites through the use of point-to-point links. Branch sites cannot exchange data with other branch sites without going through the central site.
Mesh
provides high availability but requires that every end system is interconnected to every other system. Each link is essentially a point-to-point link to the other node.
end systems are chained to each other and terminated in some form on each end.
BUS
End systems are connected to their respective neighbor forming a ring
Ring
refers to the direction of data transmission between two devices
duplex communication
both devices can transmit and receive on the media but cannot do so simultaneously
Half-Duplex communication
Both devices can simultaneously transmit and receive on the shared media.
Full-duplex communication
two basic access control methods for shared media
contention-based access
controlled access
contention-based access
all nodes are operating in half-duplex, competing for the use of the medium.
methods of contention-based access
-Carrier sense multiple access with collision detection (CSMA/CD) used on legacy bus-topology Ethernet LANs
-Carrier sense multiple access with collision avoidance (CSMA/CA) used on Wireless LANs
controlled access
each node has its own time to use the medium
multiaccess networks that use controlled access
Legacy Token Ring
Legacy ARCNET
These networks operate in half-duplex mode
Wireless LAN (CSMA/CA), Legacy bus-topology Ethernet LAN (CSMA/CD), Legacy Ethernet LAN using a hub (CSMA/CD)
The NIC compares data transmitted with data received, or by recognizing that ___ ___ is higher than normal on the media. The data sent by both devices will be corrupted and will need to be resent.
signal amplitude
Ethernet hub is also known as
Multiport repeater
CSMA/CA
In wireless environments it attempts to avoid them by waiting before transmitting.
