Glossary Terms
This is a glossary of terms commonly used in discussions about community broadband. Many of these terms, and any terms that we have not included, most likely have definitions available on Wikipedia as well.
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astroturf
Definition from Wikipedia: A form of advocacy often in support of a political or corporate agenda designed to give the appearance of a “grassroots” movement. The goal of such campaigns is to disguise the efforts of a political and/or commercial entity as an independent public reaction to some political entity—a politician, political group, product, service or event.
asymmetrical
Internet connections have two components – a downstream and upstream. When the two speeds are not comparable, the connection is termed asymmetric. Typically, phone and cable companies offer much slower upload speeds than download, in part because the Internet tended to be a download-centric system in the 90’s and early 00’s. However, users increasingly need faster upstream connections to take full advantage of modern applications.
backhaul
A general term for the segment of a network between the core and the edge. An example: the connection from a community network hub in a small town to a carrier hotel where it connects to the Internet backbone.
bandwidth
The rate at which the network can transmit information across it. Generally, higher bandwidth is desirable. The amount of bandwidth available to you can determine whether you download a photo in 2 seconds or 2 minutes.
bit
The base unit of information in computing. For our purposes, also the base unit of measuring network speeds. 1 bit is a single piece of information. Network speeds tend to be measured by bits per second – using kilo (1,000), mega (1,000,000), and giga (1,000,000,000). A bit is a part of byte, they are not synonyms. Bit is generally abbreviated with a lower case b.
BTOP
Broadband Technology Opportunities Program – established by the 2009 stimulus legislation, a program to disburse $4.7 billion to improve broadband access and literacy throughout the country.
byte
The base unit for file storage. Comprised of 8 bits (just to confuse you – if you don’t like powers of 2, stay away from computer science). A 1MB (megabyte) file is made of 8 million bits. Bytes generally refer to the size of storage whereas bits are used frequently when discussing how rapidly files may be moved. Byte is generally abbreviated with a capital B.
cable modem system
Cable television companies have offered Internet access via their cable system for more than a decade. The network architecture uses a loop that connects each subscriber in a given neighborhood, meaning they all share one big connection to the Internet.Over time, needs have increased faster than capacity on these networks. Because the cable network shares the last mile connection among hundreds of subscribers, a few bandwidth hogs can slow everyone’s experience.
cloud
Some refer to the entire Internet as a cloud – the idea being that all the information is just out there and it does not matter where. More commonly now, cloud computing refers to services such as Amazon’s S3 where users pay a fee to store information on Amazon’s servers without ever really knowing the physical location. As we gain access to faster Internet connections (particularly on the upstream) cloud services may offer cheaper means of accomplishing tasks and more reliable back ups.
conduit
A reinforced tube through which cabling runs. Conduit is useful both to protect fiber-optic cables in the ground and because one can place the conduit underground when convenient and later “blow” or “pull” the fiber cabling through the conduit.
CPE
Customer Premises Equipment – typically describes the box on the side of a house that receives and sends the signal from the network, connecting the subscriber.
DOCSIS 3
This is a technical specification that allows modern cable networks to offer considerably faster speeds than those used by earlier DOCSIS specifications. Comcast rolled out DOCSIS 3 in Minneapolis/St. Paul in early 2008, offering an”up to”50 downstream/5 upstream connection for $150/month. Note the slow upstream connection and the high price. The greatest flaw with DOCSIS 3 remains the shared nature of the last mile, meaning a few bandwidth hogs can slow everyone’s connection on that loop.
downstream
Internet connections have two components – a downstream and upstream. Downstream refers to the rate at which the user’s computer can receive data from the Internet.
Synonyms: download
DSL
Digital Subscriber Line – or Internet access offered over the phone lines. DSL allows users to use the Internet at speeds greater than dial-up while also using the phone line for telephone conversations. DSL uses frequencies not used by human voices. Unfortunately, these frequencies degrade quickly over distance, meaning customers must live within a mile of the central office to get the fastest speeds.
duopoly
A situation in which two companies own all or nearly all of the market for a given type of product or service.
fiber-optic
A system that uses glass (or plastic) to carry light which is used to transmit information. Typically, each side of the fiber is attached to a laser that send the light signals. When the connection reaches capacity, the lasers may be upgraded to send much more information along the same strand of fiber. This technology has been used for decades and will remain the dominant method of transmitting information for the foreseeable future.
FiOS
Verizon is the only large carrier building a ftth network. This network is called FiOS. Though FiOS is similar technologically to community fiber networks, we believe communities should have a strong voice in how the network is run and Verizon does not offer this.
franchise
A cable company wishing to provide television services in a community historically signed a franchise agreement with the municipal government. The agreement would specify what the community would receive from the cable company in return for access to rights of way (such as telephone poles). However, this arrangement has changed in many states recently, where states have preempted local control. Cities now are not permitted to offer exclusive franchises.
FTTH
Fiber-to-the-home. As most telecommunications networks use fiber in some part of it, FTTH is used to specify those that use fiber to connect the subscriber. Some claim they have a fiber-optic network because they use fiber to the node even when they use phone lines or a cable network over the last mile. FTTH may be more expensive to install currently, but offers significant savings in terms of maintenance when compared to copper alternatives.
FTTU
Fiber-to-the-User is used somewhat interchangeably with FTTH to describe full fiber networks.
Gbps
Gigabits per second – or one billion bits per second. 8 Gbps means that 8 billion bits are transferred each second. Using an 8 Gbps connection, it would take 1 second to transfer a 1 GB (Gigabyte) file – a compressed 90 min movie, for instance. 1 Kbps (Kilobits)<1 Mbps (Megabits)<1 Gbps
greenfield
A plot of land that will soon become a residential development. Building a broadband network is cheap in greenfields because roads, sidewalks, lawns, and buildings are not yet impediments to running the necessary wires.
HFC
Hybrid Fiber-Coax – a network that combines some fiber-optic elements (typically from the head end to a node in the field) and coaxial cable (typically the loop that connects the node to subscribers).
I-Net
Short for Institutional Network. This is the network a municipal government requires to carry out its duties. I-Net frequently refers specifically to a network built for city uses (connecting schools, for instance) by the cable company as part of the franchise agreement with the city. Cities are increasingly seeing the value of owning their own network.
Synonyms: Institutional Network
Kbps
Kilobits per second – a measure of speed. 8 Kbps means that 8 thousand bits are transferred each second. Using an 8 Kbps connection, it would take 1 second to transfer a 1 KB (Kilobyte) file – a text file, for instance. Don’t get lost in the details – when it comes to Kbps, more is faster – but anyone on the modern internet better measure their connection in Mbps. 1 Kbps<1 Mbps (Megabits)<1 Gbps (Gigabits)
last mile
Describes the final leg of a connection between a service provider and the customer. In DSL and cable systems, this is the most frequent bottleneck and the most expensive to resolve. The service provider may run a faster fiber-optic network into the neighborhood but deliver the last mile (which could be considerably less than a mile -“last”is the operative term) with a phone lines that cannot sustain fast speeds.
Synonyms: first mile
latency
The amount of time it takes for a bit to get from point A to point B. In the words of Dr. Stuart Cheshire: “If you want to transfer a large file over your modem it might take several seconds, or even minutes. The less data you send, the less time it takes, but there’s a limit. No matter how small the amount of data, for any particular network device there’s always a minimum time that you can never beat. That’s called the latency of the device.”
Mbps
Megabits per second – a measure of speed. 8 Mbps means that 8 million bits are transferred each second. Using an 8 Mbps connection, it would take 1 second to transfer an 1 MB (Megabyte) file – a photo, for instance. Don’t get lost in the details – when it comes to Mbps, more is faster. 1 Kbps (Kilobits)<1 Mbps<1 Gbps (Gigabits)
MDU
Multiple dwelling unit – most frequently apartment buildings. MDUs can offer a challenge when building a ftth network due to the need to negotiate with building owners and rewiring that may be necessary to bring fast speeds to each unit.
middle mile
Middle mile is a term most often referring to the network connection between the last mile and greater Internet. For instance, in a rural area, the middle mile would likely connect the town’s network to a larger metropolitan area where it interconnects with major carriers.
NATOA
National Association of Telecommunications Officers and Advisers. NATOA is comprised of local government officials and employees that work on cable and broadband issues – from public access television to managing the community’s rights-of-way.
NTIA
National Telecommunications and Information Administration – a division of the Department of Commerce in Washington, DC.
open access
An arrangement in which the network is open to independent service providers to offer services. In many cases, the network owner only sells wholesale access to the service providers who offer all retail services (ie: triple play of internet, phone, tv). Open access provides much more competition from which potential subscribers can choose.
overbuild
To create a network that goes into competition with an incumbent provider.
passed
Residences or businesses that have access to the network. As a ftth network is constructed, it will generally be built through a neighborhood before individual houses or businesses are connected via a drop cable (which is also a fiber-optic cable). When a house or businesses is”passed,”it means they are eligible to sign up for services (which may require a technician to hook up the drop cable).
peer-to-peer
This is a type of network that allows computers to connect directly to each other rather than organizing them via hierarchical connections. This term is most often used to describe a type of file sharing that has greatly increased bandwidth usage and allow faster downloading of the same file from multiple computers. Peer to peer technologies, such as BitTorrent, can greatly reduce the cost of distributing content to a large audience but also have been used to exchange copyrighted materials without permission. P2P connections generate a lot of traffic and are often throttled or denied access by broadband providers.
Synonyms: p2p
PEG
PEG is an acronym for Public Access, Educational, and Government video programs. These are common programming options made available to the community by the cable company in return for access to the community’s rights of way.
quadruple play
Triple-play with cell phone service. Only a few companies are starting to offer this – combining the now standard triple-play (television, phone, and Internet access) with a cell phone plan.
RUS
Rural Utilities Service – a branch of the US Department of Agriculture. RUS offers loans to entities deploying broadband in rural areas.
symmetrical
Internet connections have two components – a downstream and upstream. When the two speeds are comparable, the connection is termed symmetric. Fiber-optic networks more readily offer symmetrical connections than DSL and cable, which are inherently asymmetrical. Ultimately, purely symmetrical connections are less important than connections which offer robust connections in both ways. However, modern asymmetrical connections via DSL and cable networks offer upload speeds that are too slow to take advantage of modern applications.
T1
A data circuit that transmits at 1.544 Mbps.
Synonyms: T-1, T.1
take rate
The number of subscribers to a service – typically expressed in a percentage of those taking the service divided by the total number of people who could take the service. If a community fiber network passes 10,000 people and 6,000 people subscribe, it has a take rate of 60%. When planning the network, it will be built to be profitable at or above a certain take rate as defined in the business plan. Generally, networks require a few years to achieve take rates due to the long time it takes to connect each customer.
telco
Telephone company – a provider of telecommunications services such as voice (telephony) and data services. Also called common carriers or LECs (Local Exchange Carriers); ILECs are incumbent providers, often AT&T or Verizon.
telepresence
This term refers to a variety of attempts to use modern technology to make it seem like a person in a remote location is in the room. The more bandwidth available, the more realistic the remote person will appear. Modern telepresence applications are impressive, using sophisticated algorithms with multiple video cameras and microphones to go far beyond video-telephone systems.
triple-play
The three main services offered over these networks – television, phone services, and Internet access. Turns out that many people like to get all three from the same service provider on the same bill. Service providers frequently offer deals that will lower the cost on these packages. Typically, television breaks even or loses money whereas the service provider makes the most profits from phone and Internet access.
upstream
Internet connections have two components – a downstream and upstream. Upstream refers to the rate at which the user’s computer can send data to the Internet. DSL and cable networks frequently offer upload speeds at only 1/10 of the downstream speeds. This is one of the main reasons DSL and cable networks are insufficient for the modern Internet.
Synonyms: upload
USF
Universal Service Fund – a federal program with four programs: high cost (subsidizes the high cost of services in rural areas), low income (includes Lifeline and Link Up discounts to those in poverty), rural health care (reduced rates to rural health care providers to ensure they have access to similar services as urban counterparts), and schools and libraries (E-Rate subsidizes telecommunication services to schools and libraries).
Wi-Fi
This is a suite of protocols that allow wireless devices to exchange information using unlicensed frequencies. Equipment carrying the Wi-Fi brand is interoperable. Recently, a number of cities and some private companies attempted to blanket their cities with Wi-Fi but the technology is not well suited to such large scale efforts. Wi-Fi has proved tremendously successful in homes and businesses on small cities.