Systems Security Certified Practitioner – SSCP – Question0951

Which of the following is a LAN transmission method?

A.
Broadcast
B. Carrier-sense multiple access with collision detection (CSMA/CD)
C. Token ring
D. Fiber Distributed Data Interface (FDDI)

Correct Answer: A

Explanation:

LAN transmission methods refer to the way packets are sent on the network and are either unicast, multicast or broadcast.
CSMA/CD is a common LAN media access method. Token ring is a LAN Topology. LAN transmission protocols are the rules for communicating between computers on a LAN. Common LAN transmission protocols are: polling and token-passing. A LAN topology defines the manner in which the network devices are organized to facilitate communications. Common LAN topologies are: bus, ring, star or meshed.
LAN transmission methods refer to the way packets are sent on the network and are either unicast, multicast or broadcast. LAN media access methods control the use of a network (physical and data link layers). They can be Ethernet, ARCnet, Token ring and FDDI.
Source: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, John Wiley & Sons, 2001, Chapter 3: Telecommunications and Network Security (page 103).
HERE IS A NICE OVERVIEW FROM CISCO: LAN Transmission Methods
LAN data transmissions fall into three classifications: unicast, multicast, and broadcast. In each type of transmission, a single packet is sent to one or more nodes.
In a unicast transmission, a single packet is sent from the source to a destination on a network. First, the source node addresses the packet by using the address of the destination node. The package is then sent onto the network, and finally, the network passes the packet to its destination.
A multicast transmission consists of a single data packet that is copied and sent to a specific subset of nodes on the network.
First, the source node addresses the packet by using a multicast address. The packet is then sent into the network, which makes copies of the packet and sends a copy to each node that is part of the multicast address.
A broadcast transmission consists of a single data packet that is copied and sent to all nodes on the network. In these types of transmissions, the source node addresses the packet by using the broadcast address. The packet is then sent on to the network, which makes copies of the packet and sends a copy to every node on the network. LAN Topologies LAN topologies define the manner in which network devices are organized. Four common LAN topologies exist: bus, ring, star, and tree. These topologies are logical architectures, but the actual devices need not be physically organized in these configurations. Logical bus and ring topologies, for example, are commonly organized physically as a star. A bus topology is a linear LAN architecture in which transmissions from network stations propagate the length of the medium and are received by all other stations. Of the three most widely used LAN implementations, Ethernet/IEEE 802.3 networks—including 100BaseT—implement a bus topology
Sources: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, John Wiley & Sons, 2001, Chapter 3: Telecommunications and Network Security (page 104). http://www.cisco.com/univercd/cc/td/doc/cisintwk/ito_doc/introlan.htm