COMM 280- EXAM 2

Landline limitations (voice network)

1. Bandwidth length 2. Traffic patterns: Voice traffic tended to be symmetrical. In addition, voice demand patterns were fairly consistent and easy to predict. Conversely, internet traffic was asymmetrical, with somewhat unpredictable patterns and bursts of demand. 3. Geography: The concepts of LATA, Local Loop, and the Telephone Switch Hierarchy did not align well with the global reach of the internet.

5G Deployments

3 flavors of atat, version ultra wideband, tmobile fast internet speeds

Why was the voice network not good for data

Bandwidth- not enough to send over large data loads Traffic patterns- busier at certain times of day but not predictable Geography-

Cloud-based products

Big three are google, aws, Microsoft. Partnering with them

Early wireless considerations

Cell towers on campus- by creamery parking deck look up, nittany deck by shrine

LTE Advanced and channel aggregation

Channel aggregation- acheves faster data rates, think about it like lanes on a highway, more lanes faster speeds, channel ag can have 5 using 20 megahertz per channel, 100 in total

What the underlying tech with 4G? Why such a big change

Everyone on the same tech- ofdma - one tech based doesnt matter lte wifimax

Duplex system gets more complicated as it goes

Half duplex simplest and multi most complicated

tower handoff

Handoffs- signal is handoff from towers

The difference between HSPA+ and OFDMA

High speed package access- 3g tech / do not get 4g unitl ofdma/ there was dishonest marketing claiming it was 4g

IaaS

Infrastructure as a Service. A cloud computing technology useful for heavily utilized systems and networks. Organizations can limit their hardware footprint and personnel costs by renting access to hardware such as servers. AWS, microsoft, and google

4G technologies - WiMAX and LTE

LTE & WiMAX emerged as two possible 4G technologies. While AT&T and T-Mobile initially marketed their HSPA+ networks as 4G, the reality was that the underlying network technology was still 3G (until they deployed LTE)

4G vs 5G

Latency for 5G is very low, robot balancing a ball 5G had it quick but took 4G a little time

Legacy software development

New version comes out what would be some challenges - Microsoft has multiple programs/software - Long drawn out process - Development can be impacted by the greater good - Keep what you have or have to go to a brick and mortar store

How can signal get diminished by quality

Propagation delayed, reflection in the line gives you echo

How does a wireless device connect to a network?

Turn on phone and looks for closest wireless tower, do you belong on my network, mobile number what links you to your carrier and serial number (elements of handset), now we see you are in LA lets change your tower and now handset has info via control channel not voice channel

VoIP - benefits, use cases, limitations

VoIP- where voice became data, 1 and 0s Benefits- you can take it anywhere you want, scalability (it is very simple to add/remove additional devices to the network), lower costs- different prices for nights and weekends not anymore 1. save money 2. simplified network 3. scalability, portability, global Limits- voice quality dropped packets, 911 may take that extra second to get 911 to you because diff area code, power lines down no longer phones work, national secrutity hacking 1. voice quality, power requirement, 911, national security

T-mobile and sprint merger in april 2020

Who might come up as a carrier now - Dish and amazon Do we need a fourth carrier

cloud benefits and privacy implications

Yahoo and msn there is an opportunity here, get online however you want but then we will give you a free email, email does not download to desktop all within the cloud, no downloading during the cloud, benefits anywhere in the world access, device irrelevant, make updates faster if they wanted

Voice over lte-

voice on ip network but mobiltoty to it

Wireless transition from analog to digital

voice only to voice AND data (Sprint PCS, Motorola/iDEN, Nextel)

Who is responsible for allocating that spectrum

- FCC- spectrum is allocated by auctions - Us treasury gets the $$$ - Downsides (Easiest for big companies to stay big, possible monopoly)

Bandwidth

- More bandwidth more data can be travel, number of up and down signal in a second, absorption- weakening of the signal - Lower frequency long distance but Can't carry as much data - High frequency can carry a lot of data but not long distances

How phone knows correct time

- Reach out to closest tower to make sure phone belongs- authentication - Sends back via control channel - Updates handheld device and the time

Local/long distance calling

- Telephone calls can be Local (same LATA), Local Long Distance (Intra-LATA), Long Distance (Inter-LATA). Other terms: - LATA - Local access and transport area (long distance is lata) - Local Loop - the physical link from the customer to the carrier (also called "Last Mile") (infrequent connection upgrades) - Trunk Line - connection point between equipment (not homes) - P.O.P - point of presence (a connection point) - C.O. - central office (a switching point) - Inter-eXchange Carrier - provides connection to a different LATA (long distance carriers

Voice over ip

-Voice is broken into 1 and 0s -Transition to landline to voice over internet -Benefits- save money: if you are on the internet you are just on the internet, scalability: infinitely scalable, portable: can go anywhere with that phone # -Limitations- lose power than phone wont work, voice quality not as good, national security- could be hacked, 911

**Unlicensed Spectrum**

-Wi-Fi networks have emerged as a critical element of in-home and enterprise connectivity. Unfortunately, unprotected Wi-Fi networks have proved to be an easy entry point for hackers to compromise networks and obtain valuable consumer/enterprise data. -Examples Walkie talkies, house alarm systems, car tolls, microwave ovens, invisible fences, garage door openers -Do all spectrums need to be licensed -Microwaves, walkie talkies, wifi, dog fences, garage doors, ezpass

Telephone switch hierarchy

1 is international and 5 is dial tone there are 5 levels to improve network performance and provide economies of scale, a telephone switch hierarchy was developed

*Turning on a phone after plane*

1. Reach out to closest tower to make sure phone belongs- authentication 2. Sends back via control channel 3. Updates handheld device and the time Powering on a wireless device Tower approves you then can send data Airplane mode- phone still working but no longer reaching out to a wireless network so time would not update

*Six Main Benefits of Cloud Computing with Amazon Web Services*

1. Trade Capital Expense for Variable Expense - pay as you consume resources 2. Lower Variable Expense - companies are unable to match AWS' prices due to their scale 3. Capacity When Needed - taking the guesswork out of scaling a business, scale up or down as needed 4. Dramatically Increase Speed & Agility - from 6-20 weeks to add a single server to provisioning hundred/thousands of servers in minutes. This leads to greater experimentation and innovation. 5. Resource Utilization - spend resources on developing differentiated products and services, not infrastructure 6. Global - provide a global solution in minutes with 9 AWS regions all over the world

The technology shift from 3G to 4G

4g doesn't use cdma or others now uses OFDMA, ltwe was selected in end lead to development Vacuum, Video, screen sizes, device types

Switch hierarchy

5 classes, 1 is international and 5 is dial tone

Channel aggregation

5 megahetz channel- to create faster speeds

IP

ALL ONES AND ZEROS

Legacy landline telephones - elements and architecture

Anatomy Microphone- (transmitter) moveable speaker diaphragm that is sensitive to amplitude and frequency. Converts human voice and sends analog electrical signals out into the voice network Earphone- (receiver) receives the electrical signal produced by the transmitter. The varying levels of electricity produce varying levels of magnetism. The magnetic variance causes the diaphragm to produce sound that corresponds with the transmitter

Difference between FDMA/TDMA/CDMA networks

Fdma- classroom is only for this class no other class can use it ever (not efficent) TDMA- have it for a period of time then class comes in after (More efficient- all of europe said tdma) CDMA- ten classes in here at once but can only hear your class, (Very very efficient- get more out of network)

What purpose for 4 W circuit

For long distance call

Half/Full Duplex and Multiplex communication

Full- 1 to 1 calls half- walkie talkeis multi- zoom and group conferences half is simpliest and multi is most complicated

The impact Smartphones have had on application development

IOS and android- ios is apple sole owner, ios is a closed operating system, apples primary rev model come from iphones or selling devices in general, android by google that is an open system, with open there is multiple handset providers like Samsung, so android is more popular around the world, direct to consumer- like app development, people just switched to get an iphone now on at&T, itunes came out with ipod and that needed to be successful

How does Apple make their money?

Iphones sales- device sales business

Frequency shit

Low freq is good because it goes further distances and can pass though objects but cant carry a lot of data High freq can carry a lot of data short range and cant pass though shit FCC is responsible for allocating spectrum, auction to the highest bidder, money goes to the us treasury

T-Mobile/Sprint merger

Merger changed because 4 to 3 carriers now, amazon and dish potential new carriers at first spring tried to get tmobile but ended up the other way

Legacy software development/limitations

Microsoft best buy dell limitations, software development schedule Microsoft was in charge, had to make a decision to go to best buy by the update and update at home

Concept of spectrum reuse

Not adjacent cells you are able to reuse that spectrum over and over as long as not adjacent, hexagon shape, carriers don't have to but more spectrum

VoLTE and its unique product capabilities

Now there was a mobilty elements to VoIP Routing voice traffic over an IP network, similar to VoIP but with a mobility element. Lower Power Consumption, Interactive Services, HD Voice, Video Calling, call switching

Authentication

Providers with prepaid phones they will shut you off immediately no matter what

Spectrum piece- reusing spectrum- very expensive so

Resume spectrum as long as non adjacent cells

Exam question

State college to altoona - local State college to LA - long distance

AWS Virtuous Circle

Trade Capital Expense for Variable Expense - pay as you consume resources Lower Variable Expense - companies are unable to match AWS' prices due to their scale Capacity When Needed - taking the guesswork out of scaling a business, scale up or down as needed Dramatically Increase Speed & Agility - from 6-20 weeks to add a single server to provisioning hundred/thousands of servers in minutes. This leads to greater experimentation and innovation. Resource Utilization - spend resources on developing differentiated products and services, not infrastructure Global - provide a global solution in minutes with 9 AWS regions all over the world

Verizon stands out for 5G by calling it ultrawideband

Verizon thinks they are doing 5G the right way

What is a modem and why is it important

combination of MOdulator and DEModulator, wanted to send data through landline, everything with data is 1s and 0s

Behind the scene channel

control channel

Wireless handphone

first company for portable call- Motorola

Verizon different but at&T and tmobile same - all ended up on the same tech

for odfma and hspa+

T Mobile has been doing the best financially consistently and verizon had more people leaving than coming on to their service

lab shit

Wireless spectrum and network elements

wireless - Base Station (cell site) - provides a wireless signal by utilizing a transceiver and antenna. The base station transmits/receives wireless signals for a carrier. Base stations operate from 869 MHz to 894 MHz. - Mobile Device - receives signal base station signal and transmits from 824 MHz to 849 MHz. - Channel - the pair of transmit signals (base station and mobile device) form the channel. Why do you think transmit/receive pairs are needed Network elements - TSO - Mobile Telephone Switching Office. Behaves similar to the the Central Office in a PSTN. As such, the MTSO is the heart of the cellular network. MSC - Mobile Switching Center. Responsible for routing the mobile calls (mobile to mobile and mobile to landline). Billing information is typically captured by the MSC. Control Channel - only carries cellular system data. Primarily responsible for call setup. There is a forward and reverse control path between the base station and handset to set up the call. Voice Channel - paired frequencies that handle the call traffic (voice and data). Similar to the control channel, the voice channel has a forward and reverse path. Triangulation Carrier is looking at the overlapping of signal

Origin of cloud

yahoo, msn - Microsoft and yahoo don't want to be in the internet service industry just free email products - Email lives in the cloud never on the device - Can switch internet service providers as much as you want - Not geographically bound - Device irrelevant - Rapid development cycles, don't need to go to a physical store just automatically updated on the cloud Gmail - Google did this to gain more data to serve better ads