Lesson 4 Flashcards
Physical diagrams describe what
wiring layouts
Logical Diagram
describes that paths through which data moves
Which diagram describes how data moves
Logic diagram
Common physical topologies are
Star
Bus
Ring
Mesh
Physical Bus Description
Nodes are connecged in a linear fashion
T connector connecst each node to the network cable
Signal can reflect off the ends of the cable
Signal bounce
signals that reflect off the ends of the network cable
What can alleviate signal bounce
Terminators
Termination
Applying a resistor or other device at the end of a cable
Impedance Mismatch does what
impeded signal flow
Ring Topology
Each node is connected to the two nearest nodes
Why is signal flow in a ring unidirectional
To avoid collisions
Each node in a ring acts like a
Repeater
Are Rings reliable
No
Dual Ring Topology
More reliable and data moves in opposite directions
Does a star use a central connectivity device
Yes
What is a star central connectivity device
Hub
Switch
Will a fail node bring down a bus, ring or star
Ring
What will bring down a star topology
Failed central connectivity device
Are star nodes aware of one another
No
Are mesh nodes aware of one another
Yes
They are actually connected to one another
Mesh networks do not experience congestion and are very fast True or False
True
Is the mesh network reliable
Yes
What is a full mesh
When all nodes are connected to all nodesl the opposite is called a partial mesh
A partial mesh is sometimes referred to as what
redundant star
Is the internet a mesh or partial mesh
partial mesh
What’s a hybrid technology
exhibits more than one standard topology
Name some hybrid topologies
Star-bus
Extended Star
Star-Ring
Star Rings are commonly found in
MANs
Extended start topologies are commonly found in
LANs
Star Bus topologies are commonly found in local area networks
LANs
Do all nodes get the data in a logical bus?
Yes
In this logical topology, each node receives dat only from its upstream neighbor and retransmits data only to its downstream neighbor
Logical Ring
Logical Ring equals a physical
Star
Logical Bus equals a physical
Star
Topic B
Topic B
What info does logical topologies provide that physical topologies do not
Data transmission path
Data converges and diverges
Most popular wired network type
Ethernet because of simplicity and wide applicability
What serves as an interface between a network node and the network
NIC
Where are NIC cards located
Built into the motherboard
Located in an expansion slot
Externally connected to the computer
NICs operate in which modes
Half duplex
Full duplex
What is a transceiver
a device that has both a transmitter and receiver integrated into it
NICs have an auto negotiation feature that allows
device to perform self configuration to achieve the best possible mode of operation across a link
GBIC
Gigabit Interface Converter
Transceiver used to convert electrical signals into optical signals and vice versa
SFP
Small Form Pluggable
Transceiver is most commonly used in the 2Gbps and 4 Gbps
MAC Transceiver
Ethernet transceiver o AUO to Ethernet transceiver is a passive device that connects a 15 pin AUI Ethernet connector
Name the 802.x standards
- 2
- 3
- 3af
- 3at
- 11
What is Ethernet (802.3)
Technology and media access methods specified for LANs
Also called 802.3
Ethernet deals with which layers
Layer 1 and 2
Is Ethernet limited to ThinNet and ThihckNet
No
What is ThinNet
Ethernet that uses RG58/U
What is ThickNet
EtherNet that uses RG8
What’s an Ethernet frame
Data packet that has been encoded at the Data Link Layer (Layer 2)
The basic Ethernet frame contains how many fields
Seven
Name the Ethernet Frame Fields
Preamble Start of Frame Delimiter Destination Address Source Address Frame Type Data Frame Check Sequence
Describe a MAC address
6 Bytes long
3 Bytes belong to Org Unique Identifier
3 Bytes belong to Universal LANMAC address
Uses hexadecimal
Pg 152-154
Pg 152-154
Which standard covers Power over Ethernet
IEEE 802.3af
Why is power over Ethernet good
It allows you to deliver power to the devices via the Ethernet cable
What are AAA services for
Authentication
Authorization
Accounting
What are the two types of switches
Managed and Unmanaged
Describes a router
Works at Layer 3
Uses IP addressing
Can strip off Layer 2 info
Can routers work with non routable protocols
No
Routers only work with
Routable protocols
Name the categories of routers
Access Routers
Distribution Routers
Core Routers
Which type of router is used in a SOHO environment
Access routers
Which type of router collects data from multiple access routers
Distribution Routers
Purpose of a core router
Located at the center of network backbones
Used to connect multiple distribution routers located in different builidngs
Purpose of a Gateway
Any device or software that translates one network protocol to another
Gateways work a which layer
Layer 3
What is a firewall
software or hardware to protect a device or network
What’s an Analog modem
device that modulates signals to encode them into a digital format
Modems are classified by
Bps
Baud rate
Name some legacy network devices
Repeater
Hub
Bridge
What is a collision domain
Nodes contend for access to the same physical medium because all nodes hear all transmissions
Name two collision domains
Single hub domains
Buses
Does each port on a switch become its own collision domain
Yes
24 Port switch has 24 collision domains
If a 24 port switch is placed in full duplex mode, will any collisions occur
No
Broadcast Domain
Network segment on which broadcasts occur
Can micro segmentation stop broadcasts
No
What do switches do with broadcasts by default
It sends it out to all ports
What do routers do with broadcasts by default
They block broadcasts by default
If a router has two Ethernet interfaces, does it has two broadcast domains
Yes
Micro segmentation
A switch separates all nodes from each other logically until there is a need to connect them
MAC Table
A switch learns the address of all nodes connected to its ports and places those addresses into a table.
A MAC table is also called a CAM table
Managed switch are sometimes called
Intelligent switches
How do you connect to a managed switch
via a web browser or management port
Name some switch types
Multilayer
Content
Name some switch modes
Cut Through
Fragment Free
Store and Forward
Describe Spanning Tree Protocol
Layer 2 protocol
Used to prevent routing loops
Do switches send broadcasts and multicast out all ports
Yes
Switching Loops
Redundant paths between switches
Two switches connected using two different links
Ring of switches connected to each other
Broadcast Storm
d
Rapid Spanning Tree Protocol
Replaced STP
Usually takes about 20 seconds
Shortest Path Bridging
Replaces STP
Enables multiple path routing
Blocking
User data is not sent or received
Listening
BPDUs are processed by the switch. It does not forward frames. It waits for information to determine if it should return to the blocked state. It does not update MAC tables
Learning
Learns source addresses from received frames. Addresses are added to the switching database. MAC address table is updated. No frames are forwarded
Forwarding
Data is sent and received on a port in this state. BPDUs are monitored to determine if the port should return to the blocked state
Disabled
A port that has been manually disabled
Topic E
Topic E
What is a primary benefit of using switches and VLANs
To implement the concept of VLANs to segment a network
What is a VLAN
logical grouping of ports on the switch
Who determines which ports are grouped together
Admin
Nodes that plug into a VLAN switch can only communicate with the nodes that belong to the same VLAN
T
What is tagging
When a VLAN port group is extended to another device
What is a native VLAN
A VLAN that handles traffic that is not tagged
Name some uses for VLANs
- Traffic management
- It can be used to isolate a group of computers on their one VLAN
- To separate nodes based on traffic type and the need for quality ofservice
Can VLANs be extended beyond a single switch
t
Can VLAN tagging keep different customer’s traffic separate
Y
Can VLANs communicate with one another
Only if you use a router to send packets between them; otherwise. VLANs can only communicate with nodes located within that VLAN
How can ports be assigned on a VLAN
Manually configuring each port on a switch to belong to a particular VLAN
Associating a VLAN with a node’s MAC address
What is the advantage of assigning a port on a VLAN
If a user moves between locations, pligging a device into different ports the node always stays in the same VLAN
What is port mirroring
The practice of duplicating all traffic on one port in a switch to a second port
What are the types of port mirroring
Local port mirroring
Remote port mirroring
What is trunking
Linkd]s can be combined to increase bandwidth and reliabiity
Link Aggregation Control Protocol
a method to control the bundling of several physical ports
What is the primary purpose of link aggregation
is to allow redundant links to combine their bandwidth together without causing spanning tree loops
VLAN Pooling
mechanism whereby WAPs can choose among several different VLANs to assign to incoming Cleats connections
VLAN Trunking Protocol
messaging protocol that switches use to update each other’s VLAN database
Name three VTP modes
Server Mode
Client Mode
Transparent Mode
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