Network Implementations Flashcards
describes a network’s physical wiring layout or shape
Physical Topology
network topology in which the nodes are arranged in a linear format, and a T-connector connects each node directly to the network cable. Signals can reflect off the ends of the cable, so you must install 50 ohm terminators to prevent reflection. Using 10Base-2 coaxial cable (ThinNet) to connect computers is a classic example of a
physical bus topology
network topology in which each node is connected to the two nearest nodes: the upstream and downstream neighbors. The flow of data in is unidirectional to avoid collisions. are potentially unreliable, as the failure of a single node can bring down the entire network.
Physical Ring Topology
A variant of the ring topology which allows the use of two counter-rotating rings, in which each ring carries data in the opposite direction. Faster, as data can be sent through the shortest path between a sender and the receiver.
Dual Ring Topology
a network topology that uses a central connectivity device, such as a switch, with individual physical connections to each node. The individual nodes send data to the connectivity device, and the device then forwards data to the appropriate destination node. Reliable and easy to maintain, as a single failed node does not bring down the whole network. However, if the central connectivity device fails, the entire network fails.
Physical Star Topology
a network topology in which each node is directly connected to every other node.
Physical Mesh Topology
any topology that exhibits the characteristics of more than one standard topology.
Hybrid Topology
Logical topology where one node transmits, all nodes hear it as if they were connected by a bus regardless of the physical topology.
Logical Bus Topology
a network topology in which each node receives data only from its upstream neighbor and re-transmits data only to its downstream neighbor, regardless of the physical layout of the network. In the days of token ring, a central device (multistation access unit or MAU/MSAU) would connect the devices in a star shape, but the wiring was such that the electrical path was actually a never-ending loop, passing from the device to a node, back to the device, to another node, back to the device, and so forth.
Logical Ring Topology
this logical topology only works on a physical bus topology where all nodes are wired onto the same bus cable and a central device polls each node to see if it needs to transmit data. Usually managed by a multiplexer or MUX.
Logical Star Topology
a device that serves as an interface between a network node and the network. To connect to a network, whether wired or wireless, a node must have this installed. Some feature two or more LED indicator lights. These are generally green and amber, indicating connectivity and activity, respectively.
Network Adapters (NICs)
this standard describes Layer 1 and Layer 2 specifications for wireless LANs in the 2.4, 3.6, 5, and 60 GHz frequency bands.
802.11
this standard provides a framework to make wireless networks more secure. It makes use of existing protocols that enable the user to be authenticated by a central authority. Tied to AUTHENTICATION.
802.1x
this standard is used to support Ethernet-based virtual LANs. It specifies how Ethernet frames are tagged for handling over the network. Tied to VLAN TAGGING.
802.1q
this standard describes Power over Ethernet (PoE) technology, which enables networks to deliver electrical power and standard data over Ethernet cabling.
How much power is supplied?
802.3af
Up to 15.4 W of DC power can be supplied to each powered device, with 12.95 W being ensured to the powered device due to power dissipation during delivery.
