Internet Box - All about

ADSL (Asymmetric Digital Subscriber Line) is currently the most widely used technology for Internet access by individuals.
ADSL (Asymmetric Digital Subscriber Line) is currently the most widely used technology for Internet access by individuals.

Internet box

ADSL is a technology developed to be able to pass computer data through telephone lines.

The high frequency bands of ADSL are those not used by the telephone (300 - 3400 Hz), multiplexing and modulation techniques are implemented.
However, using the high frequencies of the telephone line implies the use of a filter on both sides of the line so that there is no disturbance.
The streams are asymmetric, which means that in ADSL, a subscriber can send data (uplink) at a lower rate than it can receive (downlink).
ADSL has made it possible to obtain speeds 10 to 500 times higher than previous Internet access techniques, thus offering providers the possibility of offering services other than Internet access, as is the case with Triple-Play offers.

Subscribers whose telephone line is not unbundled can, at best, only benefit from a speed of 2 Mbps, which is not enough to pass audio/video streams.
The speeds proposed by ADSL are ideal rates, because ADSL is very sensitive to the attenuation of telephone lines.
Thus, the longer a line will be between a subscriber and his telephone exchange, the less the speed he will be able to obtain via ADSL will be. Similarly if the line is damaged, or if it has electronic devices.
The Set-Top Box (STB) is a device provides subscribers to be able to benefit from the special offers Triple Play.
The Set-Top Box (STB) is a device provides subscribers to be able to benefit from the special offers Triple Play.

The Set-Top-Box

The Set-Top Box (STB) is a device that the ADSL ISP (sometimes free) provide their subscribers to qualify for the Triple Play offers.
It is a box that connects to the telephone line, and who has at least a TV
Digital terrestrial TV
Two major types of broadcasting exist for television; the so-called analogue and digital television. The analogue television appeared the first. This is widely spread around the world. However, this type of diffusion is ageing and not very innovative.
For this reason analogue television is currently tending to disappear to give way to digital television. Digital television is largely based on analogue televisio......
output (SCART
The Peritel
PERITEL refers to a coupling device and an audio/video connector that has been mainly used in Europe. It simply plugs in devices (TVs) that have analog audio/video functions using a 21~pin connector.
There are three types of connectors : the socket on the devices, the male/male cord and the extension cord. Peritel connectors are more often found on equipment marketed in Europe. Today analogue television is b......
or RCA
RCA
An RCA connector, sometimes called Cinch, is a type of electrical connector commonly used to transmit audio and video signals. The RCA name from the Radio Corporation of America, who designed it in the early 1940s for the internal connection of the reading head of the phonographs.
It has a simple design and low cost. The connecting plug is called RCA plug or Jack to phono, phonograph or C......
), a telephone connector (RJ11
RJ11
RJ11 – Regitered Jack 11 – is used for the landline. It is an international standard for connecting the fixed telephone to the telecommunications network.
RJ11 uses a 6-slot connector. In this one RJ11 has 6 slots (positions) and two drivers, the standard is written 6P2C. The information transmitted on the line can be digital (DSL) or analog. The telephone cable that arrives at the subscriber has 4 cond......
or phone jack), and an Internet Connector (RJ45
RJ45
RJ45 - Registered Jack - is the wired standard that allows the network connection for example to the Internet via a box. This type of cable has 8 pins of electrical connections.
This cable is also called ETHERNET cable its connector is called 8P8C connector (8 positions and 8 electrical contacts). This connector is physically compatible with the RJ11 connector if an adapter is used. On RJ45 computer cabling in......
, USB
USB
The USB bus is also said to \Hot pluggable\, that is to say that you can connect and disconnect a USB with the PC on. The system installed on the PC (Windows, linux...) recognizes it immediately. The USB has a very interesting feature : it's the mode standby when not using the device. Also known as \Power conservation\ : Indeed the USB bus gets suspended after 3 ms if it is no longer used. During this mode, the co......
, WiFi
WiFi
In the family of networks 'Wireless', are those which are built according to the 802.11 standards family networks WiFi. The most common fields of application are : - in the personal environment, the deployment of a small network, mainly intended to share an internet connection broadband.
- in-house, to allow easy connection of mobile workstations (laptop) to the network or a part of the network of the compa......
, etc.).

The STB is somehow a mini-computer capable to communicate via ADSL with the ISP, and offer services to subscribers.
Some STB have extra services (sometimes paying) and features (Routing IP/NAT) Internet connection sharing, Media Player (destined for television), streaming multipost (i.e., receive more than one TV
Digital terrestrial TV
Two major types of broadcasting exist for television; the so-called analogue and digital television. The analogue television appeared the first. This is widely spread around the world. However, this type of diffusion is ageing and not very innovative.
For this reason analogue television is currently tending to disappear to give way to digital television. Digital television is largely based on analogue televisio......
channel), etc...

Access to the Internet
Access to Internet is the first type of service offered through ADSL. Other services of a Triple Play by being dependent on one, ADSL offer
We will focus on the operation of this service initially.

The connection between the user and the STB can usually be done in three different ways :

- USB
USB
The USB bus is also said to \Hot pluggable\, that is to say that you can connect and disconnect a USB with the PC on. The system installed on the PC (Windows, linux...) recognizes it immediately. The USB has a very interesting feature : it's the mode standby when not using the device. Also known as \Power conservation\ : Indeed the USB bus gets suspended after 3 ms if it is no longer used. During this mode, the co......
connection : he is a serial link that allows the user to directly connect his computer to the STB. It does not specify any particular communication protocol to use. However, communication with the STB is done, most of the time, using either the ATM protocol, Ethernet protocol. It can also be that the STB works only as a classic ADSL modem using this type of connection, then forcing the use of the PPP protocol over ATM (PPPoA) or Ethernet (PPPoE) in this case.
- Ethernet connection : it is in fact a Fast Ethernet (100 Mbps) connection that allows the user to connect to the STB with a network card.
- WiFi
WiFi
In the family of networks 'Wireless', are those which are built according to the 802.11 standards family networks WiFi. The most common fields of application are : - in the personal environment, the deployment of a small network, mainly intended to share an internet connection broadband.
- in-house, to allow easy connection of mobile workstations (laptop) to the network or a part of the network of the compa......
connection : most of the time, this is an optional module paying that allows the user to connect to the STB using a wireless connection, type 802 .11b/g.
Of course, network used here is the IP protocol. His level of the user's computer configuration is performed using a DHCP server,
implemented in the STB, either within the premises of the ISP.

In general, the suppliers provide only a single IP address per subscriber (subscriber can however get more by paying, but it is not common with all suppliers). The latter can also change in time (dynamic IP),
but given the nature almost permanent dynamic ADSL, IP connections offer no benefit to providers.
To share the connection Internet between different computers, there are usually two solutions :

If we want to be able to connect Ethernet to the Internet, please then allow sharing the link Ethernet (hub or switch) devices. In WiFi
WiFi
In the family of networks 'Wireless', are those which are built according to the 802.11 standards family networks WiFi. The most common fields of application are : - in the personal environment, the deployment of a small network, mainly intended to share an internet connection broadband.
- in-house, to allow easy connection of mobile workstations (laptop) to the network or a part of the network of the compa......
the link is naturally shared. Finally, using the USB
USB
The USB bus is also said to \Hot pluggable\, that is to say that you can connect and disconnect a USB with the PC on. The system installed on the PC (Windows, linux...) recognizes it immediately. The USB has a very interesting feature : it's the mode standby when not using the device. Also known as \Power conservation\ : Indeed the USB bus gets suspended after 3 ms if it is no longer used. During this mode, the co......
connection.
There must be a device that makes the bridge between the USB
USB
The USB bus is also said to \Hot pluggable\, that is to say that you can connect and disconnect a USB with the PC on. The system installed on the PC (Windows, linux...) recognizes it immediately. The USB has a very interesting feature : it's the mode standby when not using the device. Also known as \Power conservation\ : Indeed the USB bus gets suspended after 3 ms if it is no longer used. During this mode, the co......
link and a link (mainly Ethernet) network, and is compatible with the STB USB
USB
The USB bus is also said to \Hot pluggable\, that is to say that you can connect and disconnect a USB with the PC on. The system installed on the PC (Windows, linux...) recognizes it immediately. The USB has a very interesting feature : it's the mode standby when not using the device. Also known as \Power conservation\ : Indeed the USB bus gets suspended after 3 ms if it is no longer used. During this mode, the co......
drivers.
This course does not work if the connection to the Internet depends on the Protocol PPP.
This type of connection sharing allows to use the three types of access to the STB at the same time to connect to the Internet.
connection of a subscriber to its STB.
connection of a subscriber to its STB.

Connection to the Set-Top-Box

The STB is connected to the telephone line from the user. At the other end of the phone line is DSLAM 8, which has the task to make the bridge between the equipment of the users
(via the STB) and the service provider's network. The DSLAM at the level of the local telephone exchange (more technically known as the node of the Subscriber connection), and can be equipment belonging to the supplier or to the historical operator,
(it depends on the level of unbundling of the Subscriber). A same DSLAM is connected to a set of subscribers (from the same ISP).
The number of subscribers by DSLAM Depending on the manufacturer.

The communication between the STB and the DSLAM is performed using ADSL technology. This technology from telecommunications, it almost always involves the use of the ATM protocol at the top,
the latter being simple enough to be implemented easily in telecommunication devices and offering very good management of the 9QoS.
In the case of an offer Triple Play, it may also be an extension of the ATM that is used (RFC 2684) Protocol to allow the transport of several streams (protocols) different via ATM.

These flows are usually four in number :
- one audio (telephony)
- one for the video data (TV
Digital terrestrial TV
Two major types of broadcasting exist for television; the so-called analogue and digital television. The analogue television appeared the first. This is widely spread around the world. However, this type of diffusion is ageing and not very innovative.
For this reason analogue television is currently tending to disappear to give way to digital television. Digital television is largely based on analogue televisio......
)
- one for Internet data
- a final for the three previous flow control data.
The ADSL throughput depends on the contract of the Subscriber, of the distance between the installation and the central office where the DSLAM to which it is connected.
The ADSL throughput depends on the contract of the Subscriber, of the distance between the installation and the central office where the DSLAM to which it is connected.

IP flow

The ADSL throughput depends on the subscriber contract, but above all, the distance between the installation of the user and the central office where the DSLAM to which it is connected.
Currently, this will of 128 kbit/s to 25 Mbit/s (ADSL2 +) for the stream down (download), and 128 Kbps to 1 Mbps (ADSL2 +) for the flow amount (upload), knowing that only users living near their central office can benefit from the best rates.
The limits of flow rates per user are carried out at the level of the DSLAM.
Thus, in ADSL, sold flow is only seldom guaranteed. Moreover, it is specified by a debit ATM, which does not match the IP flow, and, indeed, still less useful flow available to the user.

Finally, it should be noted that all of the sold DSL speed is not totally dedicated to Internet access in a Triple Play offer. Indeed, this flow is shared between the flow of data (Internet),
Audio (telephony) and the video stream (television), knowing that the latter is extremely greedy.

However, this share is adaptive, that is to say that while a stream is to use the connection, it can enjoy all of the flow (that is specific to ATM).

contact@instrumentic.info         
© 20016-2021 instrumentic.info

www.instrumentic.info
is an ad-free site
Take a moment to help us