OSI Data Link Layer: MAC Techniques Flashcards
Methods of Shared MAC Media
- Controlled Access
- Contention-based Access
A method of Shared MAC media wherein only one device transmits at a time; devices wanting to transmit must wait for their turn
Controlled Access
A method of Shared MAC media wherein devices can transmit at the same time
Contention-based Access
Mechanisms that resolve contention
- CSMA/CD for Ethernet Networks
- CSMA/CD for 802.11 Wireless Networks
Contention-based Access for Shared Media uses what process to first detect whether the media is carrying a signal
Carrier Sense Multiple Access (CSMA)
Other name for Controlled Access for Shared Media
Scheduled Access or Deterministic
Other name for Contention-Based Access for Shared Media
- Non-deterministic
What is CSMA/CD
Contention-Based Access for Shared Media/Collision Detect
It is a CSMA method that monitors the media for the presence of a data signal
CSMA/CD
What is CSMA/CA
Contention-Based Access for Shared Media/Collision Avoid
It refers to an arrangement of the nodes and the physical connections between them
Physical Topology
It is a CSMA method that examines the media for the presence of a data signal (?)
CSMA/Collision Avoid
It refers to the way a network transfers frames from one node to the next
Logical Topology
How is MAC implemented in a point-to- point topology
It connects two nodes directly so MAC protocol can be very simple; all frames on the mediacan only travel to or from two nodes
How is MAC implemented in a Multiaccess Topology
It enables a number of nodes to communicate by using the same shared media
How is MAC implemented in a Ring topology
Each node in turn receives a frame and uses a controlled MAC technique token passing
Three Parts of a Frame
Header
Data
Trailer
Device addresses in layer 2 are referred to as what?
Physical Addresses
Frame header fields
Start of Frame Field
Source and Destination address fields
Priority/Quality of Service Field
Type Field
Logical Connection control field
Physical link control field
Flow control field
Congestion Control Field
Frame trailer fields
Frame Check Sequence Fields
Stop Field
Process that refers to the determination of whether the frame arrived without error
Error Detection
It refers to creation of a logical summary contents of the frame by the transmitting node
Cyclic Redundancy Check
Ethernet Frame fields
Preamble
Destination Address
Source Address
Type
Data or Payload
Frame Check Sequence (FCS)
Options that PPP can make within a session
- Authentication:
- Compression
- Multilink
