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Baris 6:
Negara dengan penetrasi penggunaan jalurlebar tertinggi di dunia adalah [[Korea Selatan]], di mana 23,17% (data Desember [[2003]]) penduduknya memanfaatkan koneksi jenis ini.
== Sekilas ==
<div style="float: right; margin: 0 0 1em 1em;">
{| class="wikitable"
|+''Broadband transmission rates''
!Connection!!Transmission Speed
|-
|[[DS-1]] (Tier 1)|| 1.544 Mbit/s
|-
|[[E-carrier|E-1]]||2.048 Mbit/s
|-
|[[DS-3]] (Tier 3)|| 44.736 Mbit/s
|-
|[[OC-3]]|| 155.52 Mbit/s
|-
|[[OC-12]]|| 622.08 Mbit/s
|-
|[[OC-48]]|| 2.488 Gbit/s
|-
|[[OC-192]]|| 9.953 Gbit/s
|-
|[[OC-768]]|| 39.813 Gbit/s
|-
|[[OC-1536]]|| 79.6 Gbit/s
|-
|[[OC-3072]]|| 159.2 Gbit/s
|}
</div>
Jalur lebar sering dipanggil '''internet kecepatan-tinggi''', karena biasanya memiliki kecepatan aliran data yang tinggi. Umumnya, hubungan ke pelanggan dengan kecepatan 256 kbit/d (0,256Mbit/d) atau lebih dianggap sebagai internet jalur lebar. [[International Telecommunication Union]] Sektor Standarisasi ([[ITU-T]]) rekomendasi I.113 mendefinisikan jalur lebar sebagai kapasitas pengiriman yang lebih cepat dari kecepatan utama [[ISDN]] pada 1,5 sampai 2 Mbit/d. Definisi [[Federal Communication Commissiona|FCC]] dari broadband sekitar 200 kbit/d dalam satu arah, dan jalur lebar canggih paling tidak 200 kbit/d dalam dua arah. [[OECD]] mendefinisikan jalur lebar sebagai 256 kbit/d dalam paling tidak satu arah dan kecepatan ini yang paling diterima di seluruh dunia.
Dalam praktek, jalur yang diiklankan tidak selalu tersedia bagi pelanggan; ISP seringkali memiliki jumlah pelanggan yang lebih banyak dari hubungan yang bisa ditangani, dengan anggapan bahwa seluruh pelanggan tidak menggunakan internet dengan kapasitas penuh dalam waktu yang sama. Strategi ini dapat diterima, namun dengan berkembangnya sistem [[pembagian file]] [[rekan-ke-rekan]], seringkali membuat masalah bagi ISP yang memiliki pelanggan lebih dari kapasitas peralatan mereka.
Karena [[lebar jalur]] yang diberikan kepada pelanggan terus meningkat, pasar dapat mengharapkan bahwa pelayanan [[video atas permintaan]] dapat disalurkan melalui internet akan menjadi semakin populer, meskipun begitu saat ini pelayanan tersebut masih membutuhkan jaringan yang khusus. Kecepatan data dalam kebanyakan jasa jalur lebar masih tidak mencukupi untuk menyediakan video berkualitas bagus, karena [[MPEG-2]] masih membutuhkan 6 Mbit/d untuk hasil yang bagus. Format [[MPEG-4]] menghantarkan video kualitas-tinggi pada 2 Mbit/d, di penghujung akhir kemampuan [[modem kabel]] dan [[ADSL]] sekarang ini. Format [[Ogg Tarkin]] diharapkan dapat menghantarkan performa yang setanding.
== Teknologi ==
Teknologi standar di banyak tempat adalah [[DSL]], diikuti oleh [[modem kabel]]. Teknologi yang lebih baru untuk jalur telepon [[twisted pair]] seperti [[VDSL]] dan hubungan [[optik fiber]]. Untuk wilayah yang tidak dicakup oleh layanan kabel, banyak komunitas telah memulai memasang jaringan [[Wi-Fi]].
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[[ISDN]] is an older telephone data service that can operate at speeds of up to 128 kbit/s. It is therefore not really considered a true form of broadband, but it does have the advantage that it can share an existing phone line, and it has no distance limitations like DSL. When a phone call occurs, some of the bandwidth is allocated to the call, reducing the connection speed. When the call ends, the connection increases speed again. ISDN is a relatively low-cost option for rural users with otherwise terrible dialup access speeds, but it is starting to be phased out and is no longer available in some areas.
One of the great challenges of broadband is to provide service to potential customers in areas of low [[population density]], such as to farmers and ranchers. In cities where the population density is high, it is easy for a service provider to recover equipment costs, but each rural customer may require thousands of dollars of equipment to get connected. A similar problem existed a century ago when electrical power was invented. Cities were the first to receive electric lighting, as early as 1880, while in the [[United States]] some remote rural areas were still not electrified until the 1940's, and even then only with the help of federally-funded programs like the [[Tennessee Valley Authority]] (TVA).
Several rural broadband solutions exist, though each has its own pitfalls and limitations. Some choices are better than others, but depend on how proactive the local phone company is about upgrading their rural technology.
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=== Internet satelit ===
{{utama|Internet satelit}}
Hubungan ini menggunakan sebuah [[satelit]] di [[orbit geostationary]] untuk meneruskan data dari perusahaan satelit ke setiap pelanggan. Internet satelit merupakan salah satu cara paling mahal untuk mendapatkan akses internet jalur lebar, namun di daerah pedesaan cara ini mungkin adalah satu-satunya cara. Namun biaya terus menurun dalam waktu-waktu belakangan ini dan dapat bersaing dengan pilihan kecepatan tinggi lainnya.
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Satellite Internet also has a high [[Latency (engineering)|latency]] problem caused by the signal having to travel 22,000 miles (35,000 km) out into space to the satellite and back to Earth again. The signal delay can be as much as 500 [[millisecond]]s to 900 milliseconds, which makes this service unsuitable for applications such as [[multiplayer]] Internet gaming or live [[interactive]] access to a distant computer, but tolerable for just basic email access and web browsing.
There is no simple way to get around this problem. The delay is primarily due to the [[speed of light]] being only 186,000 miles per second (300,000 km/second). Even if all other signalling delays could be eliminated it still takes the electromagnetic wave 233 milliseconds to travel from ground to the satellite and back to the ground, a total of 44,000 miles (70,000 km) to travel from you to the satellite company.
Since the satellite is being used for two-way communications, the total distance increases to 88,000 miles (140,000 km), which takes a radio wave 466 ms to travel. Factoring in normal delays from other network sources gives a typical connection latency of 500-700 ms. This is far worse latency than even most dialup modem users experience, at typically only 150-200 ms total latency.
=== DSL remot ===
This allows a service provider to set up DSL hardware out in the country in a weatherproof enclosure. However, setup costs can be quite high since the service provider may need to install fiberoptic cable to the remote location, using [[horizontal boring]] equipment at a cost of $1 million per mile ($600/m). Also, the remote site has the same distance limits as the metropolitan service, and can only serve an island of customers along the [[trunk line]] within a radius of about 7000 feet (2 km).
Remote DSL access is becoming a sore point for many rural customers, as the technology has been available for some time now and phone companies keep promoting its availability, but at the same time the phone companies keep dragging their feet and are not doing anything to install the remote services. In the United States, this is particularly a problem with the very large multistate conglomerates that serve mostly rural areas.
=== DSL repeater ===
This is a very new technology which allow DSL to travel longer distances to remote customers. One version of the repeater is installed every 10,000 feet (3 km) or so along the trunk line, and strengthens and cleans up the DSL signal so it can travel another 10,000 feet (3 km).
=== Power-Line Internet ===
This is a new service still in its infancy that may eventually permit broadband Internet data to travel down standard high-voltage [[power lines]]. However, the system has a number of complex issues, the primary one being that power lines are inherently a very noisy environment. Every time a device turns on or off, it introduces a pop or click into the line. Energy-saving devices often introduce noisy [[harmonics]] into the line. The system must be designed to deal with these natural signaling disruptions and work around them.
Broadband over power lines (BPL) has developed faster in Europe than in the US due to
a historical difference in power system design philosophies. Nearly all large power
grids transmit power at high voltages in order to reduce transmission losses, then
near the customer use step-down transformers to reduce the voltage. Since BPL
signals cannot readily pass through transformers, repeaters must be attached to
the transformers. In the US, it is common for a small transformer hung from a
utility pole to service a single house. In Europe, it is more common for a somewhat
larger transformer to service 10 or 100 houses. For delivering power to customers,
this difference in design makes little difference, but it means delivering BPL over
the power grid of a typical US city will require an order of magnitude more
repeaters than would be required in a comparable European city.
The second major issue is [[signal strength]] and operating [[frequency]]. The system is expected to use frequencies in the 10 to 30 [[Megahertz|MHz]] range, which has been used for decades by [[ham radio]] operators, as well as international [[shortwave]] broadcasters and a variety of communications systems (military, aeronautical, etc.). Power lines are unshielded and will act as transmitters for the signals they carry, and have the potential to completely wipe out the usefulness of the 10 to 30 MHz range for [[shortwave]] communications purposes.
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=== ISP tanpa kabel ===
Koneksi ini biasanya menggunakan sistem radio [[Wi-Fi]] [[IEEE 802.11]] untuk menghubungkan titik yang berjauhan, tetapi juga dapat menggunakan sistem komunikasi radio tenaga-tinggi lainnya.
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Traditional 802.11b was licensed for omnidirectional service spanning only 300 to 500 feet. By focusing the signal down to a narrow beam with a [[yagi antenna]] it can instead operate reliably over a distance of many miles.
Rural Wireless-ISP installations are typically not commercial in nature and are instead a patchwork of systems built up by hobbyists mounting antennas on [[radio masts and towers]], agricultural [[storage silo]]s, very tall trees, or whatever other tall objects are available.-->
=== T-1/DS-1 ===
[[T-1]]/[[DS-1]] adalah satu jenis hubungan yang memungkinkan bagi pelanggan di pedesaan yang menginginkan kecepatan jalur lebar, tetapi biayanya sangat tinggi tergantung jarak ke penyedia.
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These are highly-regulated services traditionally intended for businesses, that are managed through Public Service Commissions in each state, must be fully defined in PSC [[tariff documents]], and have management rules dating back to the early 1980s which still refer to [[teletypes]] as potential connection devices. As such, T-1 services have very strict and rigid service requirements which drive up the provider's maintenance costs and may require them to have a technician on standby 24 hours a day to repair the line if it malfunctions. (In comparison, ISDN and DSL are not regulated by the PSCs at all.)
People attempting to establish rural service via a Wireless ISP, ISDN, or T-1 will run into an additional cost issue, where the physical connection (or [[local loop]]) is considered separate from the actual Internet service provided from a [[Point of Presence]] (POP). This is as if you had to pay the water utility to rent the water main in the ground, in addition to paying to get water delivered through the main from the tower. For a T-1, for example, in the US the loop alone may cost $1200 per month, and the 1.5 megabit per second business-class Internet service (with fixed a [[IP address]] and a [[subnetwork|subnet]]) may cost an additional $1000 per month. Attempting to reduce monthly costs by establishing your own non-profit Wi-Fi network and sharing the T-1 connection costs has an additional pitfall: your service provider may want to charge you an additional "ISP reseller's fee" of $800 per month.
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== Pranala luar ==
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