Module five day two Flashcards
Why would I use non-routable space for internal IP addresses
IP addresses are scarce and expensive, non-routable space is secure.
NAT
Network address translation. A way to map many private addresses inside a local network to a public IP address Before trans frame the information onto the internet
who uses nat?
organizations that won multiple devices to employ single IP address, and most home routers.
What makes network configuration easier?
configuring local DNS and DHCP server
Is non-routable address space intended to access the internte?
no, unless you use Network Address Translation to translate non-routable IP addresses to public ones, allowing them to access the internet.
what network layer does NAT operate at?
3, the Network layer.
What reserves an alias IP address for a device in routable range?
NAT
What allows a private network to connect with the internet through the translated public IP?
NAT
WAN
Acts like a single network, but spans across multiple physical locations
What do WAN usually require?
I contract a link across the internet with my internet service provider
What handles sending data from one site to another?
ISP
Where does each LAN network end?
a demarcation point where the ISP network takes over.
what is the area between each demarcation point and an ISPs actual core network?
local loop
What is an example of a local loop?
something like a T carrier line, high speed optical connection to the provider’s regional office.
What would connect to the ISP’s core network and the internet at large?
WAN
What is a physical Connection that leaks a customer’s premises to a telecommunication service providers network?
local loop, local tale, subscriber line, last mile
How do WAN work?
busing different protocols at the data link layer to transport data from one site to another.
WAN protocols are sometimes at work
at the core of the internet itself.
What can be connected Through the internet with connections provided by internet service providers in each locale?
WAN
What can be formed by connecting multiple LAN sites using equipment and cables leased from a regional internet service provider?
WAN
what can be configured through virtual private networks
security for WAN across the public internet
what are hardware devices that act as intermediate systems to route data amongst the LAN member groups of a WAN using a private connection? they also facilitate and organization’s access to a carrier network. they also have a digital modem interface for the WAN, which works at the OsI link layer, and an ethernet interface for the LAN
WAN router, border router, edge router.
what is software developed to address the unique needs of cloud based WAN environments? they can be used alone or in conjunction with a traditional WAN, simplify how WAN are implemented, managed, maintained. the overall cost to operate them is less than the overall cost of equipping and maintaining a traditional WAN.
SD-WAN, software defined WAN.
Why do SD-WAN replace lines leased from an internet service provider by linking regional LAN together to build a WAN?
to reduce operational costs
what are four techniques available to optimize network traffic and data storage on a WAN?
compression, deduplication, protocol optimization, local caching, traffic shaping
what technique involves reducing file size to improve network traffic efficiency? it has algorithms available for text, image, video, etc. also the center and receiver will need apps that offer the same algorithm to encode and decode files.
compression
what technique prevents files from being stored multiple times within a network to avoid wasting expensive hard drive space? one copy of a file is kept in a central location and all other copies are file pointers to the single copy of the file, n which saves hard drive space, makes performing data backup efficient, reduces the amount of time to recover data from data lost disasters
deduplication
what technique improves the efficiency of network protocols for applications that need higher bandwidth low latency
protocol optimization
what are three techniques in traffic shaping
bandwidths throttling, rate limiting, use of complex algorithms
what technique on a WAN stores local copies of network and internet files on a usual computer to reduce the need to resend the same information across the network every time the file is accessed?
local cashing
what’s an example of local caching
WAN optimization products storing shared files at a physical LAN location when groups of employees at the location tend to request the same set of files frequently.
what technique involves optimizing network performance by controlling the flow of network traffic?
traffic shaping
what traffic shaping technique involves controlling network traffic volume during peak use times?
throttling bandwidth
what traffic shaping technique involves capping maximum data rates and speeds
rate limiting
what traffic shaping technique involves classifying and prioritizing data to give preference to more important traffic?
use of complex algorithms
would are used in conjunction with WAN routers to perform the task of distinguishing between a private LAN and the related public WAN?
WAN protocols
what are examples of WAN protocols and techniques?
packet switching, frame relay, asynchronous transfer mode (ATM), high level data control HLDC), packet over synchronous optical network (SONET) or synchronous digital hierarchy (SDH), multi protocol label switching (MPLS)
what method of data transmission involves breaking messages down into multiple packets? with each packet having a header that includes information on how to reassemble the packet as well as the intended destination of the packets.
Packet switching
in packet switching, why are packets triplicated?
to prevent data corruption
what is done with triplicated packets?
they are sent separately over optimal routes, then reassembled when they reach their destination.
what happens to triplicated copies of a packet when they reach their destination
they are reassembles and the copies are compared with each other to detect and correct data corruption. at least to of the three copy should match.
what happens of the data from packet switching cannot be reassembled or data corruption is evident in all three copies?
the destination makes a request to the origin to resend the packet
Which method of data transmission is an older technology originally designed for use and integrated services digital network lines?
Frame Relay
which method of data transmission is no used transmitting data between end points of WAN through a pocket switching method that works at the OSI data link and physical layers?
Frame Relay
what data communications network is used to transport data packets and frames, with the reliability minimizing the need for error checking?
a frame relay network
in frame relay what circuits are used for long term data connections and stay open even when data are not being transmitted
permanent virtual circuits
in frame relay what circuits are used in temporary session connections for sporadic communications
switched virtual circuits
put etc the frames and frame relay include?
routing address information for the destination
what is an older technology that encodes data using asynchronous time division multiplexing?
asynchronous transfer mode, ATM.
in asynchronous transfer mode how is data sent?
encoded data is packaged into small fix size cells. it can be sent over long distances which makes it useful for WAN communication.
how does ATM use routers?
as end points between ATM networks and other networks
what has ATM technology been replaced by?
internet protocol, IP
what WAN protocol involves the encapsulation or data link protocol that delivers data frames through a network, with frames including multiple fields that can hold information about start and end flags, controls, frames check sequence, and protocol use?
HLDC, High Level Data Control
What was developed to use multiple protocols to replace SLDC, Synchronous Data Link control?
HLDC
What protocol includes error correction, flow control, and data transmission through polling?
HLDC
What protocol has three modes to define the relationship between two devices, or nodes, during communications?
HLDC
What are the three modes of the HLDC protocol?
Normal response mode, asynchronous response mode, asynchronous balanced mode.
in high level data control, what is a normal response mode?
primary node must give permission to the secondary node to transmit
in high level data control, what is asynchronous response mode
the primary node allows the secondary node to initiate communication
what is asynchronist balanced mode in high level data control
both nodes can act as etc the primary or secondary nodes. they can initiate communications without permission.
what communication protocol is used for WAN transport, defining how point to point links communicate over fiber optics?
Packet over synchronous obstacle network (SONET) or synchronous digital hierarchy (SDH)
what technique for optimizing network routing replaces inefficient table lookups for long network addresses with short path labels, with labels directing data from node to node?
n multi protocol label switching MPLS
What are a popular alternative to WAN technologies
point to point vpn
Where a WAN technologies best?
when you need to transport large amounts of dataAcross lots of sites.
WAN technologies are built to be
superfast
Business cable or direct service line dsl maybe cheaper, but
it can’t handle the load required when you need to transport large amounts of data across lots of sits
what lets companies outsource all or part of their different pieces of infrastructure to other companies to manage?
the cloud
what typically hosts emails these days?
the cloud
what can a company do with their email?
they can have a cloud hosting provider host the email server, or even use an email as a service provider.
what do lots of businesses no longer require between their sites?
extreme high speed connections, WAN expense
what does a point A point VPN do
make sure different sites of a company can communicate with each other, by establishing a VPN tunnel between them.
for site to site VPN, what handles the tunneling logic?
network devices at either side
What does WAN stand for
wide area network
In a WAN what is the area between a demarcation point and the internet service provider’s core network known as
local loop
A point to point virtual private network is also known as
site to site virtual private network vpn
Who handles sending data from one site to another
internet service provider
In today’s world what are fewer devices weighed down by
physical cables
what type of networking is on the rise?
wireless networking
Where are the most common specifications for how wireless networking devices should communicate defined by?
the IEEE 802.11 standards.
what set of specifications makes up the set of technologies we call wifi?
801.11
how do wireless networking devices communicate with each other?
radio waves