Cable Internet uses coaxial cable media as a media access. Origin of this coaxial cable is only used to distribute TV signals only. In some systems, coaxial cable to distribute signals only media. In other systems, fiber optic cable is pulled from the company's cable TV service provider to various major areas. In place of the fiber optic signal is converted to flow using a coaxial cable to the homes of customers. Technology that combines fiber optic and coaxial cable for customer distribution technology, known as HFC (Hybrid Fiber-Coaxial). HFC network is a platform technology that provides three channels at once, among others, TV channels, fast internet access and telephony.
Bandwidth is transmitted over the cable TV network is divided into many channels (channel). The width of each channel is made of 6 MHz. This is because the TV signal using frequency allocation 6MHz (NTSC standard) or 7 or 8MHz (PAL standard), to conform with the standard video bandwidth of 4.2 MHz, and bandwidth HDTV (high definition TV), which has been compressed into a 6 MHz. Typically each channel used to send a broadcast., So the cables can be routed in a TV broadcast for decades. Generally, the frequency spectrum used for TV signals range between 111Mhz - 450 Mhz, whereas the coaxial cable is capable of carrying up to 1000 Mhz frequency. If initially all the channels used to transmit television broadcasts, now some of the channels used to access the Internet using a channel on an unused frequency that is then used to carry the data signal, and is usually taken at a frequency of 550 MHz and above.
Some of the canal serves as a downstream path (from the Internet to the customer), and the other serves as a pathway upstream (from customer to the Internet). Wide bandwidth or number of channels that functioned for less than the channel downstream to upstream because most customers do more download than upload. Traffic happens to cable modem subscribers are generally asymmetric. Downstream traffic is greater than upstream traffic, it is common in Internet traffic. Downstream of the traffic using that frequency of 6 MHz of bandwidth available in about 27Mbps. Bandwidth of this dishared (divided) together with the user or customer is other cable TV internet. While on the upstream side, the frequency of use varies between 200kHz, 400, Khz, 800 Khz, 1600 Khz, 3200 Khz and. If 800Khz used the large bandwidth available in about 2700 Kbps. This of course resulted in the time it takes to upload (send data from users to the Internet) much longer than the time to send data from the Internet to the customer (download).
For the Internet data transmission in both upstream and downstream, the channel is shared by all users of the service. For the narrow upstream bandwidth is divided in units of time, namely in the millisecond (1/1000 second), which is in units of time a customer can perform all "spray" the data to the Internet.
So that customers can access the Internet, cable TV operators have two choices. The first option is to build own and operate its Internet service. That is, the operator serves as a broadband server. He can provide Internet service standards, such as surfing websites, e-mail box, and chat. Or other services such as providing space for storing data files, audio, and video belongs to the customer. This way customers do not need to subscribe to an ISP (Internet Service Provider) other. That is, he had no choice other than the ISP cable TV operator in question. The second option, the cable TV operators to work with another ISP. This cooperation in the operation of the ISP license and bandwidth. Operators can work together with one or more ISPs so that more customers have a choice, although still limited. In Indonesia, of the three cable TV operators, it seems only one operator that has been providing Internet services in the form of cooperation with two ISPs.
INTERNET CABLE PROPERTIES
A. The advantages possessed
Internet via cable TV networks have several advantages over the Internet via the telephone network. One of them is Internet access for 24 hours. This can happen because the cable TV operators to enable network and service for 24 hours straight.
If customers add Internet facilities, cable TV operators will attract additional monthly subscription fee. These additional costs "fall" is cheaper than the cost to be paid when using the media for 24 hour phone line for one month.
Moreover, with cable Internet there is no need to dialing process as you would on the telephone network. No more answers to a busy tone (busy tone) when all phone lines to the ISP is solid. And, no more missed phone calls because we are busy surfing-ria.
Data transmission rates (upstream and downstream) were also higher than the transmission of data on a standard telephone network or ISDN / Integrated Service Digital Network. If the maximum data transmission speed on a standard phone line at 28.8 kbps (kilo bits per second), and by ISDN at 128 kbps, then on cable TV networks can reach 38 Mbps (Mega bits per second). Performance of data transmission speed is not affected much, close the distance between customers and service providers.
With such a high speed, we can accept audio video stream (audio video stream) is much smoother, not frozen (freeze). Thus, live video teleconference with the partners it works with audio-or video-audio chat with a family in distant places can be done with ease.
Speeds are very high-speed can be achieved if the cable is usually used in the trunk and distribution system is a fiber optic cable. Coaxial cable is only used as a drop cable, the cable link between the customer and the distribution tap ..
B. The drawback is owned
However this use has the effect of a single channel for cable modem users. When you are first connected to the Internet via a channel that is empty, then you can utilize the entire bandwidth just for you. But along with the addition of new customers, especially customers who are wasteful of bandwidth, you have to share bandwidth with it and you will experience a significant decrease in performance. This is because the use of the internet channel is allocated to be used jointly by all customers.
Possible, at the time of a full connection, the performance will be far below the theoretical. The good news, this decline in performance can be overcome by adding a new channel and the average number of users sharing each channel that is used for data transmission over the Internet.
TOOLS AND EQUIPMENT REQUIRED FOR INTERNET CABLE
A. On the customer side: Cable Modem
One of the support device is a cable Internet modem (modulator-demodulator) cable. He connects the customer with a PC computer cable TV channel. Its function is as an interface between computers and communications standard format standard format cable TV network communications.
Cable Modem is a device that enables high-speed data access (eg, internet) via cable TV networks (do not use the phone line as the modem usually). Cable modems generally have 2 (two) connectors, the one to be connected to the cable network TV outlet and the other connected to a computer (PC). Most cable modems are external devices that connect to a PC using a network card (10Base-T Ethernet) and a special cable (twisted-pair wiring). External USB (Universal Serial Bus) cable modem and cable modem internal PCI card currently under development. Sometimes people like to misunderstand the meaning of the word "Cable Modem" because it works more like a Cable modem with network equipment (LAN) rather than modem.
Speed cable modem is very varied, depending on the system applied to the modem itself, the architecture of the network cable, and the level of activity data path. In the downstream direction (from network to a computer) can reach speeds of up to 27 Mbps which is divided by a user according to the bandwidth. Some computers can connect at high speed to between 1 to 2 Mbps. However in general the manufacturer of the cable modem is set at a speed of 500 Kbps to 2.5 Mbps.
The problem, communications cable TV networks do not have a standardized communication standard. Therefore, should the cable modem supplied by cable TV operators. The selection of modems that do not correspond to the network format clearly prevents us from enjoying the Internet 24 hours. However, if the regulations have been agreed by the competent bodies, we can buy a modem with more model choices. The agencies usually issue a regulation of which is: Federal Communications Commission (FCC), International Telecommunication Union (ITU), and the Institute of Electrical and Electronics Engineers (IEEE).
In general, cable modem can not be purchased separately, this is because if the company's cable network providers to use a particular brand of networking equipment, cable modem then the only brand that can be used. For this reason in general, users of cable modem service can rent the equipment (cable modem), so it does not have to face the risk of an outdated product (generally the problems faced by computer users).
B. On the Cable TV service providers: CMTS and other supplies
Cable Modem Termination System (CMTS) located at the headend cable TV network. CMTS takes the data stream sent a number of customers through the upstream, and then sent to the ISP or the Internet connection. At the headend, cable TV operators also need to have (or lease from the ISP) some equipment (hardware and software) to Internet facilities.
Equipment-equipment are: multiple server computers for accounting and logging. Dynamic Host Configuration Protocol (DHCP) for assigning and administration of IP addresses (Internet Protocol) for its customers. Also server control to the protocol that epithet: Data Over Cable Service Interface Specifications (DOCSIS). DOCSIS is the main standard used for the implementation of the United States for Internet access cable TV subscribers.
Data is passed downstream flow to all customers (who are currently connected) with a mechanism such as the ethernet network, the network system that is widely used on a Local Area Network (LAN). On this mechanism, a block of data intended for a customer can receive and read by the customer in question.
When a customer sends data to the CMTS via upstream path, the data will not be readable by other customers. In order to be multi-access, the narrower upstream bandwidth is divided into chunks of time (in the order of milliseconds).
In each period will be delivered some time pieces, each containing one data from one customer. Or in other words, these customers are on-line, alternately use upstream channels in the order of milliseconds. The way this time sharing may work well if: the number of customers connected (line) are few and most of the subscribers to send short commands.
A CMTS is able to handle 1,000 customers connected to the Internet through a single channel width of 6 MHz. Because a single channel can be passed 30 Mbps to 40 Mbps, it is clear that the data transfer speed is higher than the data transfer speed telephone networks.
However, speed is not always achievable due to the cable TV network consists of the branches. All customers in the branches using the same bandwidth. As a result, when the number of customers who access the Internet increases, the speed of data transfer decreases. This is because Internet bandwidth to be used interchangeably, as in the LAN.
Picture the Internet over cable TV lines:
To maintain a high-speed access, it is appropriate if the cable TV operators perform remediation efforts. For example, the addition of channels to the Internet, the use of optical fibers with higher bandwidth and faster server with more capacity. Or other efforts to maintain and even improve customer satisfaction
Bandwidth is transmitted over the cable TV network is divided into many channels (channel). The width of each channel is made of 6 MHz. This is because the TV signal using frequency allocation 6MHz (NTSC standard) or 7 or 8MHz (PAL standard), to conform with the standard video bandwidth of 4.2 MHz, and bandwidth HDTV (high definition TV), which has been compressed into a 6 MHz. Typically each channel used to send a broadcast., So the cables can be routed in a TV broadcast for decades. Generally, the frequency spectrum used for TV signals range between 111Mhz - 450 Mhz, whereas the coaxial cable is capable of carrying up to 1000 Mhz frequency. If initially all the channels used to transmit television broadcasts, now some of the channels used to access the Internet using a channel on an unused frequency that is then used to carry the data signal, and is usually taken at a frequency of 550 MHz and above.
Some of the canal serves as a downstream path (from the Internet to the customer), and the other serves as a pathway upstream (from customer to the Internet). Wide bandwidth or number of channels that functioned for less than the channel downstream to upstream because most customers do more download than upload. Traffic happens to cable modem subscribers are generally asymmetric. Downstream traffic is greater than upstream traffic, it is common in Internet traffic. Downstream of the traffic using that frequency of 6 MHz of bandwidth available in about 27Mbps. Bandwidth of this dishared (divided) together with the user or customer is other cable TV internet. While on the upstream side, the frequency of use varies between 200kHz, 400, Khz, 800 Khz, 1600 Khz, 3200 Khz and. If 800Khz used the large bandwidth available in about 2700 Kbps. This of course resulted in the time it takes to upload (send data from users to the Internet) much longer than the time to send data from the Internet to the customer (download).
For the Internet data transmission in both upstream and downstream, the channel is shared by all users of the service. For the narrow upstream bandwidth is divided in units of time, namely in the millisecond (1/1000 second), which is in units of time a customer can perform all "spray" the data to the Internet.
So that customers can access the Internet, cable TV operators have two choices. The first option is to build own and operate its Internet service. That is, the operator serves as a broadband server. He can provide Internet service standards, such as surfing websites, e-mail box, and chat. Or other services such as providing space for storing data files, audio, and video belongs to the customer. This way customers do not need to subscribe to an ISP (Internet Service Provider) other. That is, he had no choice other than the ISP cable TV operator in question. The second option, the cable TV operators to work with another ISP. This cooperation in the operation of the ISP license and bandwidth. Operators can work together with one or more ISPs so that more customers have a choice, although still limited. In Indonesia, of the three cable TV operators, it seems only one operator that has been providing Internet services in the form of cooperation with two ISPs.
INTERNET CABLE PROPERTIES
A. The advantages possessed
Internet via cable TV networks have several advantages over the Internet via the telephone network. One of them is Internet access for 24 hours. This can happen because the cable TV operators to enable network and service for 24 hours straight.
If customers add Internet facilities, cable TV operators will attract additional monthly subscription fee. These additional costs "fall" is cheaper than the cost to be paid when using the media for 24 hour phone line for one month.
Moreover, with cable Internet there is no need to dialing process as you would on the telephone network. No more answers to a busy tone (busy tone) when all phone lines to the ISP is solid. And, no more missed phone calls because we are busy surfing-ria.
Data transmission rates (upstream and downstream) were also higher than the transmission of data on a standard telephone network or ISDN / Integrated Service Digital Network. If the maximum data transmission speed on a standard phone line at 28.8 kbps (kilo bits per second), and by ISDN at 128 kbps, then on cable TV networks can reach 38 Mbps (Mega bits per second). Performance of data transmission speed is not affected much, close the distance between customers and service providers.
With such a high speed, we can accept audio video stream (audio video stream) is much smoother, not frozen (freeze). Thus, live video teleconference with the partners it works with audio-or video-audio chat with a family in distant places can be done with ease.
Speeds are very high-speed can be achieved if the cable is usually used in the trunk and distribution system is a fiber optic cable. Coaxial cable is only used as a drop cable, the cable link between the customer and the distribution tap ..
B. The drawback is owned
However this use has the effect of a single channel for cable modem users. When you are first connected to the Internet via a channel that is empty, then you can utilize the entire bandwidth just for you. But along with the addition of new customers, especially customers who are wasteful of bandwidth, you have to share bandwidth with it and you will experience a significant decrease in performance. This is because the use of the internet channel is allocated to be used jointly by all customers.
Possible, at the time of a full connection, the performance will be far below the theoretical. The good news, this decline in performance can be overcome by adding a new channel and the average number of users sharing each channel that is used for data transmission over the Internet.
TOOLS AND EQUIPMENT REQUIRED FOR INTERNET CABLE
A. On the customer side: Cable Modem
One of the support device is a cable Internet modem (modulator-demodulator) cable. He connects the customer with a PC computer cable TV channel. Its function is as an interface between computers and communications standard format standard format cable TV network communications.
Cable Modem is a device that enables high-speed data access (eg, internet) via cable TV networks (do not use the phone line as the modem usually). Cable modems generally have 2 (two) connectors, the one to be connected to the cable network TV outlet and the other connected to a computer (PC). Most cable modems are external devices that connect to a PC using a network card (10Base-T Ethernet) and a special cable (twisted-pair wiring). External USB (Universal Serial Bus) cable modem and cable modem internal PCI card currently under development. Sometimes people like to misunderstand the meaning of the word "Cable Modem" because it works more like a Cable modem with network equipment (LAN) rather than modem.
Speed cable modem is very varied, depending on the system applied to the modem itself, the architecture of the network cable, and the level of activity data path. In the downstream direction (from network to a computer) can reach speeds of up to 27 Mbps which is divided by a user according to the bandwidth. Some computers can connect at high speed to between 1 to 2 Mbps. However in general the manufacturer of the cable modem is set at a speed of 500 Kbps to 2.5 Mbps.
The problem, communications cable TV networks do not have a standardized communication standard. Therefore, should the cable modem supplied by cable TV operators. The selection of modems that do not correspond to the network format clearly prevents us from enjoying the Internet 24 hours. However, if the regulations have been agreed by the competent bodies, we can buy a modem with more model choices. The agencies usually issue a regulation of which is: Federal Communications Commission (FCC), International Telecommunication Union (ITU), and the Institute of Electrical and Electronics Engineers (IEEE).
In general, cable modem can not be purchased separately, this is because if the company's cable network providers to use a particular brand of networking equipment, cable modem then the only brand that can be used. For this reason in general, users of cable modem service can rent the equipment (cable modem), so it does not have to face the risk of an outdated product (generally the problems faced by computer users).
B. On the Cable TV service providers: CMTS and other supplies
Cable Modem Termination System (CMTS) located at the headend cable TV network. CMTS takes the data stream sent a number of customers through the upstream, and then sent to the ISP or the Internet connection. At the headend, cable TV operators also need to have (or lease from the ISP) some equipment (hardware and software) to Internet facilities.
Equipment-equipment are: multiple server computers for accounting and logging. Dynamic Host Configuration Protocol (DHCP) for assigning and administration of IP addresses (Internet Protocol) for its customers. Also server control to the protocol that epithet: Data Over Cable Service Interface Specifications (DOCSIS). DOCSIS is the main standard used for the implementation of the United States for Internet access cable TV subscribers.
Data is passed downstream flow to all customers (who are currently connected) with a mechanism such as the ethernet network, the network system that is widely used on a Local Area Network (LAN). On this mechanism, a block of data intended for a customer can receive and read by the customer in question.
When a customer sends data to the CMTS via upstream path, the data will not be readable by other customers. In order to be multi-access, the narrower upstream bandwidth is divided into chunks of time (in the order of milliseconds).
In each period will be delivered some time pieces, each containing one data from one customer. Or in other words, these customers are on-line, alternately use upstream channels in the order of milliseconds. The way this time sharing may work well if: the number of customers connected (line) are few and most of the subscribers to send short commands.
A CMTS is able to handle 1,000 customers connected to the Internet through a single channel width of 6 MHz. Because a single channel can be passed 30 Mbps to 40 Mbps, it is clear that the data transfer speed is higher than the data transfer speed telephone networks.
However, speed is not always achievable due to the cable TV network consists of the branches. All customers in the branches using the same bandwidth. As a result, when the number of customers who access the Internet increases, the speed of data transfer decreases. This is because Internet bandwidth to be used interchangeably, as in the LAN.
Picture the Internet over cable TV lines:
To maintain a high-speed access, it is appropriate if the cable TV operators perform remediation efforts. For example, the addition of channels to the Internet, the use of optical fibers with higher bandwidth and faster server with more capacity. Or other efforts to maintain and even improve customer satisfaction
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