Digital Subscriber Lines
Fast and affordable Internet access has become a big issue for private users and small businesses. Today users have many different options concerning Internet access. One can use a 56k/28k modem, cable modem, wireless, Ethernet, an ISDN connection, a T1 or T3 connection, or a DSL connection. Each method of connection has advantages and disadvantages concerning security, cost, and speed. A newer technology for users is DSL or a Digital Subscriber Line. DSL uses existing phone lines to send info. Unlike a dial up analog modem, a DSL connection allows voice and data to be sent at the same time on the same phone line, the bit rate is faster and the connection is continuous (no need to dial up).
DSL Technology
DSL is a technology for pushing high bit rates through "last mile" telephone connections (small gage copper less that 18,000 ft.). For most people, point A will be their home and point B will be the substation of the local phone company.
DSL modems, unlike conventional modems, establish a connection from one end of a copper wire to the other end of that copper wire: the signal does not pass into the telephone switching system. DSL modems are not limited to using only the voice frequencies passed by the standard telephone system (usually 0-4kHz), DSL modems typically use more than 100kHhz. (Day 1999)
When the local loop carrying the voice/data reaches the local phone company the loop first goes to a splitter which separates the voice from the data. The voice frequencies are sent to the traditional telephone switching network used for voice transfer. The data frequencies are wired into a DSL modem at the central office (CO) end. The resulting high-speed digital data stream coming from (or going to) the consumer is handled as digital data (not analog voice) and may be hooked into a number of networks connection to the data's destination. The data never enters the standard telephone switching system. (Day 1999)
When you connect to the ISP (Internet Service Provider) you are not connecting to the ISP over its standard modem bank, instead you are coming in over some sort of LAN/WAN (Local/Wide Area Network) data connection that the ISP has arranged with your local phone company. This is the only way an ISP can provide DSL-connected ISP service for customers. Because of the connection to the area network the DSL connection is always on, there is no need to dial up and connect to a modem.
In today's world a person should be able to pick up his phone and dial to almost anywhere in the world. Without knowing anything about switching, one would think that there phone would have to have a separate line to everyone other phone in the world. This would be quite a lot of lines into just one phone and know that this is an impossible scenario. This is why the switched network was developed. A switched network brings each subscriber line into a centralized switching system, where connections are made for each call.
The major savings were planned through the convergence of the voice traffic over the IP data network. The first step in that plan was to build a global network that supports the Quality of Service (QoS) necessary for VoIP traffic. Since the primary partner in this project is Cisco System, which supports VoIP through their range of products called Architecture for Voice, Video, and integrated Data (AVVID), the design is largely reliant on this technology (Cisco AVVID, 2002). The network consists of a switched core that delivers multiple megabytes of bandwidth to a ...
Until recently, small businesses could not afford T-1 service to connect to the network. The recent advent of cable modems has provided a cheaper alternative to this problem. Cable operators have primarily targeted consumers in their initial cable modem rollouts. Multiple System Operators (MSOs) are now selling higher priced broadband Internet services to the corporate customer. The question is, does cable modem technology provide the optimum service for a medium sized company that is dependent on the Internet for data computing and research? To answer this question, we have to evaluate the price, bandwidth, and reliability in the business network.
Leland, Eric (October 18, 2001). Voice Over IP. Is your telephone system outdated? [Electronic version]. TechSoup. Retrieved on May 20, 2004, from http://www.techsoup.org/howto/articlepage.cfm?ArticleId=334&topicid=5
There are four methods of data transmission on Internet: DSL, cable, wireless (wireless), and fiber optics. DSL is an existing copper wire of a phone line to deliver high speed internet access. Cable is to utilize a coaxial cable that connects to a television set. WIFI represents wireless that are used for Internet connection without wire. Fiber optic offers many advantages over conventional copper cable lines. It is able to transmit data much faster over greater distances and because the cable is smaller in diameter and weighs less, it makes an ideal alternative for a wide variety of cabling solutions.
First up, the Internet. The Internet is a vast collection of different networks that use certain common protocols and provide certain common services. In this section, they go into great detail about the history, like how it started as a military project, and even talk about how users gain access to the modern version through ISPs (Internet Service Providers). For our second example, the author writes about third-generation mobile phone networks, or 3G. Initially deployed in 2001, this systems offers both digital voice and broadband digital data services. One benefit to this system is mobility which comes from the ability of data to be handed off from one cell tower to
The phone system at AMS is what I would consider as your average phone and paging system. All of the phones have their own extension that can either be dialed as an extension or used as the last four numbers of the phone number. Within the network only the extension needs to be dialed with no previous number keying. I find this pretty handy when needing to contact other individuals within the company. Also, the equipment we test has multiple types of modems. Some of the baud rates we run them at are ranging everywhere from 8400 to 33600.
A modem (modulate demodulate) is a network device that both modulates and demodulates analog carrier signals (called sine waves) for encoding and decoding digital information for processing (Janssen C 2014). The most common use of modems is both for sending and receiving digital information between personal computers and for connecting to the internet. Modem is considered as an important hardware of computer and most computers in the past came with a built in modem, but now many manufacturers are not including it because of the increased popularity of broadband connections. This essay will concisely discuss the history of the modem and highlight the key developments of this technology. It will also throw light on the factors that influenced this technology and outline its current features.
Dial-up remote access is when a client uses the telecommunications infrastructure to create a physical connection with a remote access server, which is attached to a Local Area Network (LAN). The physical or logical connection between the remote access server and the remote access client is made possible through dial-up equipment. Dial-up remote access is considered a private communication portal. The nature of the dial-up equipment and WAN infrastructure varies, depending on the type of connection. There are several telecommunications technologies can make up the WAN infrastructure used in dial-up remote access. These technologies include Plain Old Telephone Service (POTS), T-carriers, Integrated Services Digital Network (ISDN), Asynchronous Transfer Mode (ATM), and Digital Subscriber Line (DSL). The remote access software dials in...
Digital Subscriber Line new technology that takes advantage of standard copper telephone line to provide secure, reliable, high-speed Internet access. DSL refers to the family of digital subscriber line technologies, such as ADSL, HDSL, and RADSL. Connection speed for DSL ranges from 1.44 Mbps to 512 Kbps downstream and around 128 Kbps upstream. Unlike traditional connections DSL such as analog modems and IDSN, DSL deliver continuous “always on” access. That means multimedia-rich websites, e-mail, and other online applications are available anytime. DSL makes it possible for you to remain online even while you’re talking on the telephone-without jeopardizing the quality of either connection. DSL is available in a spectrum of speeds. Some are best home use, while others are designed to accommodate rigorous business demands. Whether for business or the home, DSL, offers unsurpassed price/performance value compared to other online options. There are the five facts that one should know about DSL. It is remarkably fast. With DSL service, you can benefit from Internet speeds that are up to 12 minutes faster than a typical ISDN connection and 50 times faster than traditional 28.8 Kbps modems. This means that in the 12 seconds it takes to read this information, you could have downloaded a 2 megabyte presentation file or web photograph. It would take 10 more minutes (600 more seconds!) to download the same with a traditional 28.8 Kbps. It’s highly reliable. One can depend on DSL because its proven technology takes full advantage of the existing telecommunications infrastructure. It’s inherently secure. DSL network provides a dedicated Internet connection via private telephone wires, you can bypass dial-up intruders or shared network hackers. Unlike traditional dial-upp modems or cable modems. DSL protects your valuable data with the most secure connection available. It’s surprising affordable. DSL is widely recognized as the most cost-effective connectivity solution for small buisness. DSL delivers industrial- strength like speed to multiple users at only 25% of typical TI costs. There is no better price option available. DSL is also an exceptional value for home users. At about $2 a day for services that meets the needs of most people. The connection is always on. It’s ready to run every minute of the day. There’s no more logging on and off. No more busy signals or disconnects. This gives you the freedom to focus on what you want to accomplish on line rather than focusing on trying to get connected.
The world is becoming digitalised. Analogue systems in many fields of technology are being replaced by a modern digital alternative. One of the main improvements when compared to the first generation cellular systems is that GSM is a digital system. We shall take a closer look in this module what it means that the system is digital, and what benefits it offers.
Since its inception, the telephone has become one of the most important inventions of all time. Although some were skeptical about its replacement over telegrams, in the end the advent of this fine communication equipment has won the hearts of many. As a matter of fact, the telephone system had come to numerous facelifts that it literally connected the world before the internet was born. Because of its importance, homes and businesses can not live without it. In the U.S. alone, most if not all have a phone in the house.
ADSL routers : There are four Belkin ADSL modems with built in routers, the routing capabilities are simple designed for home based usage, offering minimum security features and network address translation, dynamic host control protocol (DHCP) services.
Over time the different means of receiving the internet have changed several years ago, a phone line would proved a slow connection to the internet, but would not be useful when storing and...
Making a telephone call no longer should conjure up visions of operators connecting cables by hand or even of electrical signals causing relays to click into place and effect connections during dialing. The telephone system now is just a multilevel computer network with software switches in the network nodes to route calls get through much more quickly and reliably than they did in the past. A disadvantage is the potential for dramatic and widespread failures; for as has happened.