CompTIA A+ (Anki) 2 Flashcards
What are the seven layers of the OSI model
Physical Data Link Transport Session Presentation Application
operate at the (lowest layer), layer 1 of the OSI model. This is the physical layer
There is no progoramming or intelligence built into it
It is a device that is used to connect several computers together
Any signal that is received on it is copied to all other ports
Hubs
The two types of Hubs are
active and passive
Acronym to remember the OSI model
People Do Not Touch Sexy Pamela Anderson
_ hubs include the ability to regenerate and boost the signal (repeating) before sending to other ports
can be used to extend the length of a network
Active
__ hubs are simply a physical connection point for computers
not responsible for amplifying or regenerating signals
cannot be used to extend the length of a network
Passive
operate at layer 2 of the OSI model
They are aware of address but only physical ones
ex. Mac Address
Bridges
The key functions of __ are
join similar topologies (ex. connect 2 ethernet connections)
Divide network segments into multiple collision domains
Isolate network traffic
Bridges
examine layer 2 header information from incoming packets
Based on this information, they forward the packets to a specific port
-this improves performance and reduces overhead
Switches
The advantages of __
Increases available network bandwith (becuase there are fewer packets on the network)
Increases network performance
-helps regulate the flow of traffic
-reduces collisions
Increases security (aware of address, packets that are not intended for it do not go there)
Switches
The disadvantages of __ are
Cost
-more expensive
can be difficult to troubleshoot (have to identify which ports, if two systems cannot communicate
Devices can be spoofed
Proper design and configuration is needed
Switches
The two categories of switches are __
managed and unmanaged
The __ Switch category is
often reffered to as an “intelligent switch”
has its own IP address and configuration interface
typically connected using special software or a dedicated management port
managed
the __ Switch category is
a device that performs switching without any user intervention
cannot control the functions of this type of switch
can often be more cost effective for smaller deployments
Unmanaged
__ are intelligent devices used to determie the best path for transmitting data between networks
Routing tables are used to store network addresses
Network addresses represent the routes that are available
Can transmit data across multiple networks
-large networks can be divided into smaller IP subnet
-each subnet is still a different network
Routers
__ operate at layer 3 (network layer) of the OSI model
Can support various network types
LAN
WAN
copper
fiber
can route the traffic appropriately as long as its run on TCP/IP
Routers
__ connect multiple networks together, unlike a swich or hub
do not forward broadcasts
-Broadcaset domains are broken up
Determine the best route to the destination based on
-distance (how many routers will be crossed)
-congestion (how much traffic is on given on a route)
Routers
__ are any point that enables users to access a network
commonly used when referencing a wireless access point
-eg. an access point that enables users to connect over wireless
Access points
___ and ___ operate at the physical layer (layer 1) of the OSI model
designed to improve signal range and strength by amplifying any signal they recieve
-can extend range of wifi signal on router
-can operate wirelessly or with wire
eg. used at airports
Repeaters and extenders
__ is how PCs connect to a swith via a NIC
Can be wired or wireless
PC Network Interface Card (NIC)
Network devices require at least one interface
__ is your interface
can be hard wired or modular
-modular is a card and can be replaced in motherboard easily
-hardwired means it is physically soldered onto the motherboard
NIC
__ are hardware devices used to connect to a remote network or the internet
Sends and recieve data
-telephone line
-cable line
Modems