ISTM 643 Ch. 16
What did former FCC chair Tom Wheeler say about 5G?
"5G may be the last physical network overhaul in generations as upgrades will now be only a matter of replacing software and low-cost, commodity components'
What does the following URL really say? http://www.nytimes.com/tech/index.html
"Use the Web (http://) to find a host server named 'www' in the 'nytimes.com' network, look in the 'tech' directory, and access the 'index.html' file"
What service has O3b begun to provide?
"fiber-quality" wireless service to undeserved portions of the developing world, as well as others needing connectivity outside traditional cell networks (cruise ships and US Navy)
Web hosting services
A firm that provides hardware and services to run the Web sites of others.
ICANN (Internet Corporation for Assigned Names and Numbers)
A nonprofit governance and standards-setting body that accredits registrars throughout the world
Bluetooth
A standard for short-range wireless connectivity, typically meant to eliminate cabling used for things like speakers, printers, cameras, and other devices
What is the point of shielding?
Allows the cable signals to travel longer distances without degrading and with less chance of interference
hypertext transfer protocol (http)
Application transfer protocol that allows Web browsers and Web servers to communicate with each other.
FTP
Application transfer protocol that is used to copy files from one computer to another.
Fiber to the home (FTTH)
Broadband service provided via light-transmitting fiber-optic cables.
digital subscriber line (DSL)
Broadband technology that uses the wires of a local telephone network.
load balancing
Distributing a computing or networking workload across multiple systems to avoid congestion and slow performance.
wireless spectrum
Electromagnetic frequencies used for wireless communication
protocol
Enables communication by defining the format of data and rules for exchange
What does cache poisoning do?
Exploits a hole in DNS software, redirecting users to sites they didn't request
Mobile phone services usually have a number, followed by a _________
G
broadband
High-speed Internet connections
Internet backone
High-speed data lines that interconnect and collectively form the core of the Internet
URL (uniform resource locator)
Identifies resources on the internet along with the application protocol needed to retrieve it. Often used interchangeably with "Web address"
domain name service (DNS)
Internet directory service that allows devices and services to be named and discoverable
Why are there few broadband over power line (BPL) deployments, despite it having been available for years?
It is considered to be pricier and less practical than alternatives
What is the winner in 4G technologies?
LTE (long-term evolution)
What are some attributes of net neutrality?
- Access providers have wanted to offer varying coverage, depending on the service used and bandwidth consumed - Internet content providers worry that without strong neutrality rules, ISPs may block content or favor their own offerings above rivals - If network providers move away from flat-rate pricing toward usage-based pricing, this may limit innovation
What are some attributes of Traceroute?
- Builds our the path that packets take to their destination - Built into all major desktop operating systems - Several Web sites will run it between locations - Neat way to explore how the Internet works
What are some attributes of IP addresses?
- Can be used to identify a user's physical location - The still widely used format is IPv4 and is expressed as four numbers (from 0-255), separated by periods: 216.3.128.12
What are some attributes of domain name services (DNSs)?
- Distributed database that looks up host and domain names and returns the actual IP address for them - Likened to a big, hierarchical set of phone books capable of finding Web and email servers and more - The system also remembers what it's done
What is an attribute of FTTH?
- Fastest last-mile technology and works easily over long distances
What are some attributes of NATs (network address translations)?
- Helps delay the impact of the IP address drought - Only long-term solution is to shift to a new IP scheme: IPv6 increases the possible address space from the addresses used in the current system
What are some attributes of IPv6?
- IPv6 is not backward compatible with IPv4 and transition has been very slow - When IPv6 is deployed, some of the benefits may include potentially improving speed, reliability, and security of the Internet
What are some attributes of wireless spectrum?
- Mobile wireless service providers require a wireless spectrum - Most mobile cell phone services have to license spectrum - High-stakes regional bidding wars whenever governments put new spectrum up for license
What are some limitations of FTTH?
- Need to build fiber infrastructure from scratch - Cost of buildout is enormous
What are some attributes of 5G networks?
- New 5G networks offering gigabit-plus speeds will provide a credible rival to home television and data packages offered by cable firms - Infrastructure and devices need to be upgraded - 5G may be a catalyst for all sorts of applications, including self-driving automobiles, emergency response communication, telemedicine, "bespoke" network offerings for VR, AR, and high-speed game streaming, and smart city sensors for things like traffic routing, air and water monitoring, and community safety
What are some attributes of claiming a domain name in cyberspace using a domain name registrar?
- Pay a registrar for the right to use a given name - The right is renewable over time - Some simply register domain names while others are able to run a website on their Internet-connected servers for a fee (web hosting service)
What are some attributes of Wi-Fi?
- Stands for wireless fidelity - Wi-Fi antennas are built into their chipsets - To connect to the Internet, a device needs to be within range of a base station or hotspot - Wi-Fi base stations used in the home are usually bought by end users - They are then connected to a cable, DSL, or fiber provider - Wi-Fi equipped mobile devices also offer an opportunity to act as a personal hotspot
What are some attributes of cable broadband?
- coaxial cable - Has shielding that reduces electrical interference
What are some examples of what equipment connecting in colocation facilities could be?
- high-speed lines from ISPs - telecom lines from large private data centers - servers hosted in a colo to be closer to high-speed Internet connections
What are some attributes of DSL?
- speeds vary depending on the technology deployed - Limitation - uses standard copper telephone wiring that lacks the shielding used by cable
iPads use an estimated ______ GB/month
1
Conventional mobile phones use an estimated ______ MB/month
100
Internet2 organizations have collectively set up a high-performance network running at speeds of up to _______ gigabits per second to support and experiment with demanding applications
100
What is the average demand usage for YouTube?
200-400 MB/hr
What is the average demand usage for voice calls?
4 MB/hr
What is the average demand usage for iPhone browsing?
40-60 MB/hr
US average download speeds above ________ Mbps and upload speeds near _______ Mbps are now common
40; 20
iPhones use an estimated ______ MB/month
560
How is 5G better than 4G?
5G is faster, more reliable, and has higher overall capacity than 4G networks
What is the average demand usage for net radio?
60 MB/hr
Less than a decade ago, __________ was acceptably low latency, but now trading firms are pushing below _____________ into microseconds, and soon, nanoseconds
80 milliseconds; 1 millisecond
___________ uses thick copper wire to offer broadband access
Cable broadband
NAT (network address translation)
Conserves IP addresses by mapping devices on a private network to single Internet-connected devices that acts on their behalf
bandwidth
Network transmission speeds that are expressed in some form of bits per second (bps)
Are host and domain names case sensitive?
No
How do internet service providers (ISPs) interact with one another?
Providers connect to one another, exchanging traffic and ensuring that messages can get to any other computer that's online and willing to communicate
What was the internet designed to be?
Redundant and fault-tolerant - if one network, connecting wire, or server stops working, everything else should keep on running
What is a limitation of cable broadband?
Requires customers to share bandwidth with neighbors
IP (internet protocol)
Routing protocol that is in charge of forwarding packets on the internet
Amdahl's Law
System's speed is determined by its slowest component
fault tolerance
Systems that are capable of continuing operation even if a component fails
last mile
Technologies that connect end users to the Internet
__________ wireless are provided by earth-bound base stations like cell phone towers (possible via satellite)
Terrestrial
IP address
Value used to identify a device that is connected to the Internet
What is Internet2?
a research network created by a consortium of research, academic, industry, and government firms
SMTP (simple mail transfer protocol)
a server to hold e-mail
____________ repeatedly sends a cluster of three packets starting at the first router connected to a computer
Traceroute
VolP
Transmission technologies that enable voice communications to take place over the Internet and private packet-switched networks
When do DNSs normally get hacked?
Usually happens when system security updates are not installed correctly or in a timely manner
TCP slices up the _________ into smaller chunks
Web page
peering
When separate ISPs link their networks to swap traffic on the Internet
Wi-Fi
Wireless local-area networking devices
How are routers connected?
Wirelessly or by cables
colocation facility
provides a place where the gear from multiple firms can come together and where the peering of Internet traffic can take place
In the following web address, what does "http://" represent? http://www.nytimes.com/tech/index.html
application transfer protocol
Where does peering take place?
at neutral sites called Internet exchange points (IXPs)
The host is the ___________ that you're looking for on that network
computer
routers
computing devices that connect networks and exchange data between them
In the following web address, what does "nytimes" represent? http://www.nytimes.com/tech/index.html
domain name
To stake your domain name claim in cyberspace, a firm called a _____________ can be used
domain name registrar
First residential satellite services were only used for _____________
downloads
In the following web address, what does "index.html" represent? http://www.nytimes.com/tech/index.html
file
GEO
geosynchronous earth orbit, that some later services were based on
What are fiber-optic lines?
glass lined cables that transmit light
In the following web address, what does "www." represent? http://www.nytimes.com/tech/index.html
host name
Many domains have lots of different _______
hosts
coaxial cable
insulated copper cable used by television providers
What are the "phone books" that domain name services (DNSs) are likened to called?
nameservers
The Internet is a ____________ of networks
network
UDP (user datagram protocol)
operates instead of a TCP in applications where delivery speed is important and quality can be sacrificed
internet service provider (ISP)
organization or firm that provides access to the internet
In the following web address, what does "tech" represent? http://www.nytimes.com/tech/index.html
path
What does the last-mile problem refer to?
the fact that these connections are usually the slowest part of the network
The domain name is the name of _________________
the network you're trying to connect to (usually represents an organization)
What is net neutrality?
the principal that all Internet traffic should be treated equally
How does a domain name system (DNS) remember what it's done?
through cache
Where are many users redirected in cache poisoning?
to imposter sites for the purpose of harvesting passwords and credit card data
In the following web address, what does ".com" represent? http://www.nytimes.com/tech/index.html
top-level domain
packets (or datagrams)
unit of data forwarded by a network. All internet transmissions are divided into packets
How are transmissions sent through with copper cables?
via electricity
How is the relay work done in internet protocol (IP)?
via routers
TCP (transmission control protocol)
works at both ends of internet communication to ensure a perfect copy of a message is sent
