Broadband Internet
access, often shortened to "broadband Internet" or just
"broadband", is a high data-transmission rate internet
connection. DSL and cable modem, both popular consumer
broadband technologies, are typically capable of
transmitting 256 kilobits per second or more, starting at
approximately four times the speed of a modem using a
standard digital telephone line.
Broadband Internet access became a rapidly
developing market in many areas in the early 2000s; one
study found that broadband Internet usage in the United
States grew from 6% in June 2000 to over 30% in 2003.
Modern consumer broadband implementations, up to 30
Mbit/s, are several hundred times faster than those
available at the time of the popularization of the
Internet (such as ISDN and 56 kbit/s) while costing
less than ISDN and sometimes no more than 56 kbit/s;
though performance and costs vary widely between
countries. |
Broadband
is often called high-speed Internet, because it
usually has a high rate of data. In general, any
connection to the customer of 256 kbit/s (0.256 Mbit/s)
or more is considered broadband Internet. The
International Telecommunication Union
Standardization Sector (ITU-T) recommendation I.113
has defined broadband as a transmission capacity
that is faster than primary rate ISDN, at 1.5 to 2
Mbit/s. The FCC definition of broadband is 200 kbit/s
(0.2 Mbit/s) in one direction, and advanced
broadband is at least 200 kbit/s in both directions.
The OECD has defined broadband as 256 kbit/s in at
least one direction and this bit rate is the most
common baseline that is marketed as "broadband"
around the world. There is no specific bitrate
defined by the industry, however, and "broadband"
can mean lower-bitrate transmission methods. Some
Internet Service Providers (ISPs) use this to their
advantage in marketing lower-bitrate connections as
broadband. |
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An Internet service provider
(abbr. ISP, also called Internet access provider or IAP)
is a business or organization that sells to consumers
access to the Internet and related services. In the past,
most ISP's were run by the phone company. Now, ISPs can be
started by just about any individual or group with
sufficient money and expertise. In addition to Internet
access via various technologies such as dial-up and DSL,
they may provide a combination of services including
Internet transit, domain name registration and hosting,
web hosting, and collocation.
ISP connection options
ISPs employ a range of technologies to enable customers to
connect to their network. For "home users", the most
popular options include dial-up, DSL (typically ADSL),
Broadband wireless access, Cable modem, and ISDN
(typically BRI). For customers who have more demanding
requirements, such as medium-to-large businesses, or other
ISPs, DSL (often SHDSL), Ethernet, Metro Ethernet, Gigabit
Ethernet, Frame Relay, ISDN (BRI or PRI), ATM and SONET
are more likely.
With the increasing popularity of file sharing and
downloading music and the general demand for faster page
loads, higher bandwidth connections are becoming more
popular.
How ISPs connect to the Internet
Just as their customers pay them for Internet access, ISPs
themselves pay upstream ISPs for Internet access. In the
simplest case, a single connection is established to an
upstream ISP using one of the technologies described
earlier in this article, and the ISP uses this connection
to send or receive any data to or from parts of the
Internet beyond its own network; in turn, the upstream ISP
uses its own upstream connections, or connections to its
other customers to allow the data to travel from source to
destination.
In reality, the situation is often more complicated. For
example, ISPs with more than one Point of Presence (PoP)
may have separate connections to an upstream ISP at
multiple PoPs, or they may be customers of multiple
upstream ISPs and have connections to each one at one or
more of their PoPs. ISPs may engage in peering, where
multiple ISPs interconnect with one another at a "peering
point" or "Internet exchange" (IX), allowing the routing
of data between their networks, without charging one
another for that data - data that would otherwise have
passed through their upstream ISPs, incurring charges from
the upstream ISP. ISPs who require no upstream, and have
only customers and/or peers, are called Tier 1 ISPs,
indicating their status as ISPs at the top of the Internet
hierarchy. Routers, switches, Internet routing protocols,
and the expertise of network administrators all have a
role to play in ensuring that data follows the best available
route and that ISPs can "see" one another on the Internet.
Virtual ISP
A Virtual ISP (vISP) purchases services from another ISP
(sometimes called a wholesale ISP or similar within this
context) that allow the vISP's customers to access the
Internet via one or more Points of Prescence (PoPs) that
are owned and operated by the wholesale ISP. There are
various models for the delivery of this type of service,
for example, the wholesale ISP could provide network
access to end users via its dial-up modem PoPs or DSLAMs
installed in telephone exchanges, and route, switch,
and/or tunnel the end user traffic to the vISP's network,
whereupon they may route the traffic toward its
destination. In another model, the wholesale ISP does not
route any end user traffic, and needs only provide AAA
(Authentication, Authorization and Accounting) functions,
as well as any "value-add" services like email or web
hosting. Any given ISP may use their own PoPs to deliver
one service, and use a vISP model to deliver another
service, or, use a combination to deliver a service in
different areas. The service provided by a wholesale ISP
in a vISP model is distinct from that of an upstream ISP,
even though in some cases, they may both be one and the
same company. The former provides connectivity from the
end user's premises to the Internet or to the end user's
ISP, the latter provides connectivity from the end user's
ISP to all or parts of the rest of the Internet.
A vISP can also refer to a completely automated white
label service offered to anyone at no cost or for a
minimal set-up fee. The actual ISP providing the service
generates revenue from the calls and may also share a
percentage of that revenue with the owner of the vISP. All
technical aspects are dealt with leaving the owner of vISP
with the task of promoting the service. This sort of
service is however declining due to the popularity of
unmetered internet access. |
