Case study
Software pricing: issues of client billing
Infosys, one of the major IT companies in India, has developed a new method of pricing software maintenance project. The new method is called as ‘ticket – based pricing. The customer payment will be based on three types of client request or ticket. First, customer may request for small enhancement in the software application. Second, customer may request for big enhancement in the software application and third, request may be for a bug fix. Earlier the methods used for pricing were ‘fixed price’ and ‘time and material-based pricing’. Under the ‘time and material based pricing’, customers are billed based on the number of man-hours spent on a project, while under the fixed price, the customer pays an agreed price that doesn’t vary with the manpower deployed on the project.
Infosys developed this new pricing strategy after examining the current pricing methods. Software application methods become more stable after some time. If the client opted for fixed pricing and his request for software maintenance reduced, still has to pay fixed maintenance charges. Ticket based pricing will provide flexibility to the client. Many IT majors have been trying to decrease the dependence of revenue growth on manpower addition. But this is for the first time such an attempt has been made to bring a transaction-based pricing model. The new move is expected to increase the revenue without a proportional increase in the number of employees. Contrary to this view many industry observers still feel that fixed price or time and material based pricing provide continuous revenue. The excess revenue available from these two methods can be used for reserves or hedging. In case of ticket based pricing client has to negotiate with the company every time.
a. Do you think ticket based pricing will provide continuous revenue to Infosys in the long term? Comment
Answer: Since Infosys may have two type of client that is Big & Small.
a) General small kind of client prefers to outsource their project to avoid the expenditure incurred on the installation of software and maintenance. But because of the ticket based pricing strategy the small client will also think to install the software on the basis of requirement. I think ticket based pricing is one of the best strategy adopted by the Infosys which will definitely a source of continuous revenue in the long run because of the following reason, because now they know that they are able to upgrade or may fix the problem on the basis of demand arise end have to pay accordingly. They need not to pay the fix amount of money regardless of the work alone through which the share of market for Infosys will increase amazingly.
b) Due to the fearness of fix maintenance charged occurred while the fixing of problem any big or small enhancement the big client will generally install the software of which some of its feature may not be useful for the company at all. It may unnecessary become the capital burden for the company and Infosys may not get the business of after sales and service but because of this strategy the company will install the software according to the need and utility. Further the need will arise, the company will be required for the big enhancement or small enhancement of the software end the company have to pay accordingly.
In case of any troubleshoot in the software the company is asked to pay the large fix amount on the basis of installed software
b. Compare three pricing strategies discussed here and choose any one as your choice
Answer: In case of fix price the big client will prefer to purchase new software because the amount to pay for its fixing might have purchase the new one with the enhanced technology this will further shrink the market share and attract the new entrants in the market.
In case of time any material based pricing the company may not incurred profit because The Resource involved in the fixing of problem may be the greater than the actual cost received from the client. But now the company can decides the resource factor to oversee due problem and same the cost.
Tuesday, June 23, 2009
Psychographic Segmentation
In Psychographic segmentation, buyers are classified into different groups on the basis of lifestyle or personality and values. People within the same demographic group can exhibit very different psychographic profiles.
a) Lifestyle:
People exhibit different lifestyles and goods they consume express their lifestyles.
Many companies seek opportunities in lifestyle segmentation. But lifestyle segmentation does not always work.
a) Lifestyle:
People exhibit different lifestyles and goods they consume express their lifestyles.
Many companies seek opportunities in lifestyle segmentation. But lifestyle segmentation does not always work.
example
For example, HUL launched ‘pepsodent kids’ for small children.
b) Gender: Gender segmentation has long been applied in clothing, hairstyling, cosmetics and magazines. For example, Emami segmented its personal care business on the basis of gender. For women, it is having Emami naturally fair, and for men it is fair and handsome.
c) Income: Income segmentation is a longstanding practice in such product and service categories as automobiles, clothing, cosmetics and travel. However, income does not always predict the best customers for a given product.
For example, Baja Auto limited, a leading automobile company, different bikes for different commuters. For entry level (less than Rs35000) it is Bajaj CT 100, for mid segment (greater than Rs35000 but less than Rs60000) it is pulsar and for the upper segment greater than Rs
60000 Avenger and Eliminator is positioned.
b) Gender: Gender segmentation has long been applied in clothing, hairstyling, cosmetics and magazines. For example, Emami segmented its personal care business on the basis of gender. For women, it is having Emami naturally fair, and for men it is fair and handsome.
c) Income: Income segmentation is a longstanding practice in such product and service categories as automobiles, clothing, cosmetics and travel. However, income does not always predict the best customers for a given product.
For example, Baja Auto limited, a leading automobile company, different bikes for different commuters. For entry level (less than Rs35000) it is Bajaj CT 100, for mid segment (greater than Rs35000 but less than Rs60000) it is pulsar and for the upper segment greater than Rs
60000 Avenger and Eliminator is positioned.
Demographic Segmentation
: In demographic segmentation the market is divided into groups on the basis of variable such as age, family size, family lifecycle, gender, income, occupation, education, religion, race, generation, nationality and social class. Demographic variables are the most popular bases for distinguishing customer groups. One reason is that consumers’ wants, preferences and usage rates are often associated with demographic variables. Demographic variables are easy to measure. Even when the target market is described in nondemographic terms, the link back to demographic characteristics is needed in order to estimate the size of the target market and the media that should be used to reach it efficiently. Some of the demographic variables used are :
a) Age and LifeCycle Stage: Consumers’ wants and abilities change with age. On the basis of age, a market can be divided into four parts viz., children, young, adults and old. For consumers of different age groups, different types of products are produced. For instance, different types of readymade garments are produced for consumers of different age groups. A successful marketing manager should understand the age group for which the product would be most suited and determine his marketing policy, pricing policy, advertising policy
etc., accordingly.
a) Age and LifeCycle Stage: Consumers’ wants and abilities change with age. On the basis of age, a market can be divided into four parts viz., children, young, adults and old. For consumers of different age groups, different types of products are produced. For instance, different types of readymade garments are produced for consumers of different age groups. A successful marketing manager should understand the age group for which the product would be most suited and determine his marketing policy, pricing policy, advertising policy
etc., accordingly.
Geographic segmentation
Dividing the market into different geographical units such as nations, states, regions, cities or neighborhoods. The company can operate in one or a few
Geographic areas or operate in all but pay attention to local variations. For example, Bennett, Coleman and co Ltd divided markets according to geographical units for their tabloids. In Bangalore the tabloid is known as Bangalore Mirror where as it is Mumbai Mirror in Mumbai.
Geographic areas or operate in all but pay attention to local variations. For example, Bennett, Coleman and co Ltd divided markets according to geographical units for their tabloids. In Bangalore the tabloid is known as Bangalore Mirror where as it is Mumbai Mirror in Mumbai.
Habitual buying behavior
The low involvement between the brands and few differences between the brands leads to the habitual buying behavior. For example spice powder marketed by MDH, Everest or MTR have very few difference between them and customer do not search the information to purchase particular product. Marketers whose customer represents this category should follow below listed strategies
a. Use price and sales promotions to stimulate product trial.
b. Use more visual aspects than the wordings in the advertisements
c. Television is the better media for this type of products.
d. Use classical conditioning theory to create advertisements.
a. Use price and sales promotions to stimulate product trial.
b. Use more visual aspects than the wordings in the advertisements
c. Television is the better media for this type of products.
d. Use classical conditioning theory to create advertisements.
Variety seeking buying behavior
When there are significant difference between the brands existing but customer will not involve more while purchasing, marketer identify this behavior as variety seeking buying behavior. Let us discuss the purchasing behavior of customer for biscuits. There are many varieties of biscuits available. One can purchase salt biscuits, cream biscuits, Marie biscuits, and milk biscuits of Britannia, Parle, ITC sun feast and others. The customer who purchased Britannia tiger earlier may purchase Sun feast cream biscuit next time. This doesn’t mean that quality of Britannia tiger is inferior to other brands but customer would like to try the varieties available in the market. In this situations marketer should undertake following steps
a. The market leader should encourage customers to buy repeatedly.
b. Make the product available and visible to the customer in the shopping places.
c. The firm who are not market leader should come out with sales promotion techniques to encourage customer to purchase the product.
a. The market leader should encourage customers to buy repeatedly.
b. Make the product available and visible to the customer in the shopping places.
c. The firm who are not market leader should come out with sales promotion techniques to encourage customer to purchase the product.
Dissonance reducing buying behavior
The behavior exhibited by the customer when product purchase requires high involvement but only few differences exist. For example, customers who want to purchase CTV will not find many differences between the brands but the price of the product and its technicality makes customer to involve more. One of the major disadvantages of this type of behavior is customer will show post purchase dissonance which is very difficult to control.
Analytical Marketing Systems
Also known as Marketing Decision Support systems (MDSS), this is a coordinate collection of data, systems, tools and techniques with supporting software and hardware by which an organization gathers and interprets relevant information from business and environment and turns it into a basis for marketing action. All the data which is generated through the other three systems described above are stored in a data base. The storage and retrieval capability of decision support system allows the collection and use of a wide variety of data throughout the company. Senior managers can access the data base and continually and monitor sales, markets, performance of the sales people and other marketing systems as well.
Marketing Research System
This is the third component of MIS. Marketing Research provides information to marketing manager when he/she encounters marketing problems. This may involve conducting Marketing Research survey by collecting primary data. These surveys may be conducted by the marketing department itself or a it can hire services of an external marketing research agency.
Marketing Intelligence System
This is a set of procedures and sources used by managers to obtain everyday information about developments in the marketing environment. This system supplies ‘happenings’ data unlike Internal Records System which supplies ‘results’ data. Marketing managers collect data from published sources like books, magazines and journals; by talking to customers, intermediaries and sales personnel. Some companies appoint specialists to gather consumer and competitor information, who does mystery shopping to monitor the performance of their own or competitor’s dealers. Competitor information can also be obtained by buying their product, attending their press conferences, trade shows and reading their annual reports. Companies purchase commercial information from outside suppliers and market research agencies like IMRB, ORG – MARG to obtain competitive data on their sales, advertising expenditures etc., besides their own.
Order to payment cycle
This includes information on (i) Order to payment cycle and (ii) sales information systems.
Order to payment cycle has a system which records, the timing and size of orders placed by consumers, the payment cycle followed by consumers and the time taken to fulfill the orders, in the shortest possible time. Customers place order through sales people and companies dispatch the goods and receive payments directly or through bank. A proper record system pertaining to order – to – payment cycle management helps mangers to decide on production and dispatch schedule, inventory and accounts receivable schedule and also logistics and distribution management schedules,
Sales Information Systems record everything in the sales Department, starting from Sales Call
Reports to prospects history to Sales territory and quota information for better sales planning and forecasting purpose.
Order to payment cycle has a system which records, the timing and size of orders placed by consumers, the payment cycle followed by consumers and the time taken to fulfill the orders, in the shortest possible time. Customers place order through sales people and companies dispatch the goods and receive payments directly or through bank. A proper record system pertaining to order – to – payment cycle management helps mangers to decide on production and dispatch schedule, inventory and accounts receivable schedule and also logistics and distribution management schedules,
Sales Information Systems record everything in the sales Department, starting from Sales Call
Reports to prospects history to Sales territory and quota information for better sales planning and forecasting purpose.
Age structure of the population
from the following table you can generalize that India is having 48% population who are aged less than 21 and 28% of the population are in the bracket of 2125.
Many marketing companies are focusing on these two segments. For example, Radio Indigo, FM radio station from Jupiter capital venture operates in Bangalore and Goa, plays international music.
Radio indigo targets youth segment who like western music.
Many marketing companies are focusing on these two segments. For example, Radio Indigo, FM radio station from Jupiter capital venture operates in Bangalore and Goa, plays international music.
Radio indigo targets youth segment who like western music.
Demographic Environment.
Demography: The study of population characteristics like size, density, location, gender composition, age structure, occupation and religion.
Demography statistics helps companies to develop their products in better way. These statistics are also used in developing proper supply chain, communicating product information and changing the product attributes. Demographic environment is analyzed on the basis of the following factors.
1. Age structure of the population
2. Marital status of the population
3. Geographic distribution of the population
4. Education level
5. Migration
6. Occupation.
Demography statistics helps companies to develop their products in better way. These statistics are also used in developing proper supply chain, communicating product information and changing the product attributes. Demographic environment is analyzed on the basis of the following factors.
1. Age structure of the population
2. Marital status of the population
3. Geographic distribution of the population
4. Education level
5. Migration
6. Occupation.
Invest strategy
In this position SBU
a. Should receive ample resources
b. Should support by well financed marketing efforts.
3 Protect strategy: SBU’s in this position should
a. Allocate the resources selectively.
b. Develop strategies which help in maintain its market position.
c. Generate cash needed by other SBU’s.
a. Should receive ample resources
b. Should support by well financed marketing efforts.
3 Protect strategy: SBU’s in this position should
a. Allocate the resources selectively.
b. Develop strategies which help in maintain its market position.
c. Generate cash needed by other SBU’s.
GE matrix:
1 Management can use the GE business matrix to classify SBU’s on the basis of two factors
a. Market attractiveness: Market size, entry barriers, competitors, technology and profit margin are some factors used to analyze the market attractiveness.
b. Business position can be determined on the basis of market share, SBU size, R&D capabilities and cost controls
Each cell in the model represented by the particular strategy namely, invest strategy, protect strategy, harvest strategy and divest strategy
a. Market attractiveness: Market size, entry barriers, competitors, technology and profit margin are some factors used to analyze the market attractiveness.
b. Business position can be determined on the basis of market share, SBU size, R&D capabilities and cost controls
Each cell in the model represented by the particular strategy namely, invest strategy, protect strategy, harvest strategy and divest strategy
Dogs:
SBU’s in this category generates less cash for the company as it operates in low growth and low market share. Usually companies will not invest in this category and try to liquidate or divest.
BCG matrix for ITC
1. SBU: FMCG
Industry growth rate: 24% (AC Nielson retail audit report 2007)
Company growth rate: 50% (the Hindu business line 19 th January 2008)
Company’s market share : 8% (outlook business)
Largest competitor share: HUL: 54% (outlook business)
Relative market share= 0.14
2. SBU: Paper board
Industry growth rate: 7.2% (the Hindu business line 27 th May 2007)
Company growth rate: 11% (the Hindu business line 19 th January 2008)
Company’s market share: 55%
Largest competitors share: BILT 35%
ITC’s FMCG segment analysis shows that though it is market leader in some categories their overall relative market share is 0.14. Company is in the high growth low relative market share area i.e. question mark position. ITC should invest heavily to convert its SBU position into star.
ITC’s Paperboard industry is in low growth and high market share category i.e. in cash cow segment. It should plan for investing the cash generated from this position into other businesses.
BCG matrix for ITC
1. SBU: FMCG
Industry growth rate: 24% (AC Nielson retail audit report 2007)
Company growth rate: 50% (the Hindu business line 19 th January 2008)
Company’s market share : 8% (outlook business)
Largest competitor share: HUL: 54% (outlook business)
Relative market share= 0.14
2. SBU: Paper board
Industry growth rate: 7.2% (the Hindu business line 27 th May 2007)
Company growth rate: 11% (the Hindu business line 19 th January 2008)
Company’s market share: 55%
Largest competitors share: BILT 35%
ITC’s FMCG segment analysis shows that though it is market leader in some categories their overall relative market share is 0.14. Company is in the high growth low relative market share area i.e. question mark position. ITC should invest heavily to convert its SBU position into star.
ITC’s Paperboard industry is in low growth and high market share category i.e. in cash cow segment. It should plan for investing the cash generated from this position into other businesses.
Question Mark
This category represents high market growth and low market share. SBU’s in this category has two options, either to invest heavily and bring them to star position or divest / liquidate from that position.
Model components:
Star: This category represents the high market share and high industry growth. SBU’s in this category require large investment to defend their position. SBU will turn as cash cow after some time.
Cash cows: This category represents the low growth rate and high market share which is the characteristic of SBU operating in mature industry. Here company needs less investment to hold their position. Hence it generates more cash or in management terms we say cash cow can be milked.
Cash cows: This category represents the low growth rate and high market share which is the characteristic of SBU operating in mature industry. Here company needs less investment to hold their position. Hence it generates more cash or in management terms we say cash cow can be milked.
Axis components:
1. Market growth rate: The rate at which market is growing
2. Relative market share: Market share of the SBU divided by the market share of the largest competitor.
2. Relative market share: Market share of the SBU divided by the market share of the largest competitor.
business portfolio of any one company using BCG matrix, GE matrix, and Ans off model
BCG matrix: This model is used to identify company’s SBU’s position in the market. This model identifies the SBU’s strength, weaknesses, opportunities and threats on the basis of market growth rate and relative market share. This model is also known as growth share matrix
Wednesday, April 1, 2009
The Netgear FS105 5-port Key Features
The Netgear FS105 5-port Key Features
• 5 switched 10/100 Ethernet ports
• Auto-speed and duplex mode sensing
• Vista jacks with built-in LEDs
• Versatile and compatible
• Compact and easy to install
• Plug and play, no software configuration required
• Quiet operation, no fan
• Protocol independent, compatible with TCP/IP, NetWare, Microsoft Windows
• Switch-selectable uplink port
• 12v Plug-pack power supply
• 5 year warranty for switch, 1 year for power supply
• 5 switched 10/100 Ethernet ports
• Auto-speed and duplex mode sensing
• Vista jacks with built-in LEDs
• Versatile and compatible
• Compact and easy to install
• Plug and play, no software configuration required
• Quiet operation, no fan
• Protocol independent, compatible with TCP/IP, NetWare, Microsoft Windows
• Switch-selectable uplink port
• 12v Plug-pack power supply
• 5 year warranty for switch, 1 year for power supply
The Netgear FS105 5-port
The Netgear FS105 5-port 10/100 Fast Ethernet switch brings 100 Mbps switching technology to the home and small office marketplace. The FS105 provides a cost effective way to instantaneously boost network performance while preserving your network infrastructure, including installed cabling and desktop software and hardware. Since each port is auto-speed- sensing, installation is plug and play and each connected device can easily be upgraded from 10 to 100 Mbps at any convenient time.
Netgear's workgroup switch range also includes the 8-port FS108 and the 16-port FS116. All are compact, robust, reliable and fast.
Netgear's workgroup switch range also includes the 8-port FS108 and the 16-port FS116. All are compact, robust, reliable and fast.
Netgear's non-blocking FSM726S and FSM750S Key Features
• Complete Layer 2 management- SNMP, RMON, VLAN, QoS, port trunking, and more
• 24 10/100 Mbps auto-sensing front ports (FSM726S)
• 48 10/100 Mbps auto-sensing front ports *FSM750S)
• 2 built-in front gigabit uplinks for 1000BASE-T or GBIC module
• 2 rear stacking ports- stack up to 6 units
• Friendly, intuitive browser-based interface for easy observation and control
• 24 10/100 Mbps auto-sensing front ports (FSM726S)
• 48 10/100 Mbps auto-sensing front ports *FSM750S)
• 2 built-in front gigabit uplinks for 1000BASE-T or GBIC module
• 2 rear stacking ports- stack up to 6 units
• Friendly, intuitive browser-based interface for easy observation and control
Netgear's non-blocking FSM726S
Netgear's non-blocking FSM726S and FSM750S are Layer 2 managed switch that are ideal for medium to large business with arequirement for managed switching and looking for a price/performance solution. The FSM726S has 24 10/100 ports (48 for FSM750S), 2 rear stacking ports and 2 gigabit ports - using either builtin copper gigabit or GBIC slots.
There are two management interface options - as easy-to-use, browser-based interface and a command line interface. Management features include SNMP, RMON, VLAN, QoS, port trunking, Spanning Tree, and port mirroring. All ports are auto-negotiating and support Auto Uplink™ technology. Up to six units may be stacked and the packaging includes a stacking cable and rack-mounting kit.
There are two management interface options - as easy-to-use, browser-based interface and a command line interface. Management features include SNMP, RMON, VLAN, QoS, port trunking, Spanning Tree, and port mirroring. All ports are auto-negotiating and support Auto Uplink™ technology. Up to six units may be stacked and the packaging includes a stacking cable and rack-mounting kit.
Netgear’s USB Ethernet adapter model EA101 Key Features
Key Features
• Provides Ethernet connectivity through USB port
• 10BASE-T compatibility
• Compatible with WIndows 98/ME/2000/XP
• Power, link and collision LED's
• Simple plug and play installation
• Provides Ethernet connectivity through USB port
• 10BASE-T compatibility
• Compatible with WIndows 98/ME/2000/XP
• Power, link and collision LED's
• Simple plug and play installation
Netgear’s USB Ethernet adapter
Netgear’s USB Ethernet adapter model EA101 allows you to connect Windows 98/ME/2000/XP PCs to Ethernet networks without opening your computer. Using an open USB port on either your computer or a USB hub, the EA101 enables you to connect to any standard Ethernet network. You can now add Ethernet networking to your computer without installing any internal cards. Using the latest technology available, NETGEAR once again simplifies networking for small and home based businesses.
Simple plug and play installation
External USB connector allows you to add a network connection to your computer without needing to install any hardware inside your PC. You can share files, play games, or share the Internet through a router without opening your PC.
Standard Ethernet compatible
The EA101 is a standard Ethernet adapter that will allow your computer to connect to any Ethernet network. It is also Windows 98 plug and play compatible so there is no special software to install.
Compact design
The EA101’s compact design allows you to connect to either your desktop PC or take it on the road and connect to your laptop.
Simple plug and play installation
External USB connector allows you to add a network connection to your computer without needing to install any hardware inside your PC. You can share files, play games, or share the Internet through a router without opening your PC.
Standard Ethernet compatible
The EA101 is a standard Ethernet adapter that will allow your computer to connect to any Ethernet network. It is also Windows 98 plug and play compatible so there is no special software to install.
Compact design
The EA101’s compact design allows you to connect to either your desktop PC or take it on the road and connect to your laptop.
Netgear FS116 Key Features
Key Features
• 16 switched 10/100 Ethernet ports
• Auto-speed and duplex mode sensing
• Vista jacks with built-in LEDs
• Versatile and compatible
• Compact and easy to install
• Plug and play, no software configuration required
• Quiet operation, no fan
• Protocol independent, compatible with TCP/IP, NetWare, Microsoft Windows
• Switch-selectable uplink port
• 12v in-line plug-pack power supply with IEC cord
• 5 year warranty for switch, 1 year for power supply
• 16 switched 10/100 Ethernet ports
• Auto-speed and duplex mode sensing
• Vista jacks with built-in LEDs
• Versatile and compatible
• Compact and easy to install
• Plug and play, no software configuration required
• Quiet operation, no fan
• Protocol independent, compatible with TCP/IP, NetWare, Microsoft Windows
• Switch-selectable uplink port
• 12v in-line plug-pack power supply with IEC cord
• 5 year warranty for switch, 1 year for power supply
Netgear FS116
The Netgear FS116 16-port 10/100 Fast Ethernet switch brings 100 Mbps switching technology to the home and small office marketplace. The FS105 provides a cost effective way to instantaneously boost network performance while preserving your network infrastructure, including installed cabling and desktop software and hardware. Since each port is auto-speed- sensing, installation is plug and play and each connected device can easily be upgraded from 10 to 100 Mbps at any convenient time.
Netgear's workgroup switch range also includes the 5-port FS105 and the 8-port FS108. All are compact, robust, reliable and fast.
Netgear's workgroup switch range also includes the 5-port FS105 and the 8-port FS108. All are compact, robust, reliable and fast.
Netgear wireless card Key Features
• Wirelessly connect from your office, home or public access locations with a single card
• Works with all WLAN standards – Fully compatible with IEEE 802.11b, 802.11a and 802.11g
• Up to 152-bit WEP network security helps to keep your wireless transmissions private
• WLAN Manager - users can set up location specific profiles and provides a station list of the available WLAN access points in the area
• Simple to install and use
• Works with all WLAN standards – Fully compatible with IEEE 802.11b, 802.11a and 802.11g
• Up to 152-bit WEP network security helps to keep your wireless transmissions private
• WLAN Manager - users can set up location specific profiles and provides a station list of the available WLAN access points in the area
• Simple to install and use
Netgear wireless card
Freedom of movement and flexibility of access – NETGEAR's Tri-Band Wireless PC Card gives you both in spades! Remarkably versatile, it lets you access any 802.11a/b/g wireless network from your notebook PC. Put it in your notebook PC and no matter where you are, at home, at the office, at the airport or in other public access areas, you’ll get high-speed access to corporate resources, e-mail, and the Internet. Use it to quickly network employees, saving the time and expense of Ethernet cabling, or use it to upgrade your existing network to the faster wireless standard. Easy to set up and use, it will automatically select the best connection available and adapt the settings to match. And with up to 152-bit WEP encryption, you can rest assured that your wireless network communications are private.
Netgear’s FA312 Ethernet Network Card Key Features
• 10/100 Mbps half/full duplex
• Auto-sensing (speed and duplex mode) RJ-45 interface
• Quick “one-step” Plug and Play installation
• High-throughput, low CPU utilization
• LED's display LINK, speed and activity
• 3.3 and 5 volt volt PCI - no upgrades required
• Remote Wake-on-LAN
• Limited Lifetime warranty
Operating Systems Supported
• Windows 95/98, NT 3.51 and 4.0, 2000, ME and XP
• Novell Netware Client 32 for DOS, Client for Windows
• Novell Netware Server 4.10, 4.11 and 5.0
• RedHat Linux and SCO OpenServer
If you’re a mobile professional using a Pocket PC or other Windows CE-based mobile computer, you'll want to get hold of NETGEAR’s MA701 Compact Flash Card. It gives handheld devices a new level of connectivity and versatility! Slip it into either a Type I or Type II card slot on your handheld device and you can send and receive e-mail, wirelessly synchronize with your notebook computer, and browse the Internet – all from the palm of your hand.
The indispensable MA701 delivers the ultimate in convenience to enterprise and public IEEE 802.11b wireless LAN systems for access to the Internet, e-mail, and corporate servers. Now you can work wherever you're most productive – in a conference room, on the road, in a coffee shop or hotel, or at the airport. The reliable MA701 protects your privacy with 40/64 and 128-bit WEP encryption and allows you to roam between 802.11b Access Points without resetting or reconfiguring.
• Auto-sensing (speed and duplex mode) RJ-45 interface
• Quick “one-step” Plug and Play installation
• High-throughput, low CPU utilization
• LED's display LINK, speed and activity
• 3.3 and 5 volt volt PCI - no upgrades required
• Remote Wake-on-LAN
• Limited Lifetime warranty
Operating Systems Supported
• Windows 95/98, NT 3.51 and 4.0, 2000, ME and XP
• Novell Netware Client 32 for DOS, Client for Windows
• Novell Netware Server 4.10, 4.11 and 5.0
• RedHat Linux and SCO OpenServer
If you’re a mobile professional using a Pocket PC or other Windows CE-based mobile computer, you'll want to get hold of NETGEAR’s MA701 Compact Flash Card. It gives handheld devices a new level of connectivity and versatility! Slip it into either a Type I or Type II card slot on your handheld device and you can send and receive e-mail, wirelessly synchronize with your notebook computer, and browse the Internet – all from the palm of your hand.
The indispensable MA701 delivers the ultimate in convenience to enterprise and public IEEE 802.11b wireless LAN systems for access to the Internet, e-mail, and corporate servers. Now you can work wherever you're most productive – in a conference room, on the road, in a coffee shop or hotel, or at the airport. The reliable MA701 protects your privacy with 40/64 and 128-bit WEP encryption and allows you to roam between 802.11b Access Points without resetting or reconfiguring.
Netgear’s FA312 Ethernet Network Card
Netgear’s FA312 Ethernet Network Card connects PCs to other networked computers, printers, zip drives, routers, network storage and the Internet. Plug it in and you’ll achieve high-speed transfer of all kinds of data.
Convenient! The FA312 with Wake-on-LAN, allows you to remotely access your PCs at any time to perform administrative tasks. Update your system and applications, start management asset programs, download files, track inventory—all this and more can be done outside of working hours, while network traffic is lighter.
Wake-On-Lan
Compatible with the Microsoft-led OnNow industry initiative for instantly available PCs. Supports the Advanced Configuration and Power Interface (ACPI) Remote Wake Up and Magic Packet standard.
Convenient! The FA312 with Wake-on-LAN, allows you to remotely access your PCs at any time to perform administrative tasks. Update your system and applications, start management asset programs, download files, track inventory—all this and more can be done outside of working hours, while network traffic is lighter.
Wake-On-Lan
Compatible with the Microsoft-led OnNow industry initiative for instantly available PCs. Supports the Advanced Configuration and Power Interface (ACPI) Remote Wake Up and Magic Packet standard.
Netgear products password
Netgear ADSL Modem DG632 - V3.3.0a_cx
admin password
- Admin access (HTTP)
Netgear CG814CCR - 2
cusadmin highspeed
- Comcast small business router. Default access at 10.1.10.1
- Admin access (Multi)
Netgear Dg834
n/a admin
- Admin access (Multi)
Netgear Dg834g
admin password
- it should be work also with dg834gt
- Admin access (HTTP)
Netgear DG834GT - 192.168.0.1
admin Password
- Admin access (Multi)
Netgear DM602
admin password
- Admin access (FTP Telnet and HTTP)
Netgear FM114P
n/a (none)
- Admin access (Multi)
Netgear FR114P
admin password
- Admin access (HTTP)
Netgear FSM7326P 24+2 L3 MANAGED PoE Switch
admin (none)
- Admin access (HTTP)
Netgear FVS114 - GR
admin password
- Admin access (HTTP)
Netgear FVS318
admin password
- Admin access (HTTP)
Netgear FWG114P
n/a admin
- password access (Multi)
Netgear GS724t - V1.0.1_1104
n/a password
- Admin access (HTTP)
Netgear GSM7224
admin (none)
- Admin access (HTTP)
Netgear ME102
(none) private
- Standard IP-Address is 192.168.0.5
- Admin access (SNMP)
Netgear MR-314 - 3.26
admin 1234
- Admin access (HTTP)
Netgear MR314
admin 1234
- Admin access (Multi)
Netgear MR814
admin password
- Admin access (HTTP)
Netgear RM356 - None
(none) 1234
- shutdown the router via internet
- Admin access (Telnet)
Netgear RO318
admin 1234
- Admin access (Multi)
Netgear Router/Modem
admin password
- Admin access (Multi)
Netgear RP114 - 3.20-3.26
admin 1234
- default http://192.168.0.1
- Admin access (HTTP)
Netgear RP114 - 3.26
(none) 1234
- telnet 192.168.0.1
- Admin access (Telnet)
Netgear RP614
admin password
- Admin access (HTTP)
Netgear RT314
admin admin
- Admin access (HTTP)
Netgear Sc101
admin password
- Admin access (management software)
Netgear WG602 - 1.7.x
admin password
- Default IP: DHCP or 192.168.0.227
- Admin access (HTTP)
Netgear WG602 - Firmware Version 1.04.0
super 5777364
- Admin access (HTTP)
Netgear WG602 - Firmware Version 1.5.67
super 5777364
- Admin access (HTTP)
Netgear WG602 - Firmware Version 1.7.14
superman 21241036
- Admin access (HTTP)
Netgear WGR614 - v4
admin password
- 192.168.0.1 OR www.routerlogin.net
- Admin access (Multi)
Netgear WGR614 - v6
admin draadloos
- Dutch routers
- Admin access (HTTP)
Netgear WGT624
Gearguy Geardog
- Admin access (Serial console)
Netgear WGT624 - 2
admin password
- Admin access (HTTP)
Netgear WGT634U
admin password
- Admin access (HTTP)
Netgear Wifi Router - WGT 624 v3
admin password
- slawcio26
- Admin access (HTTP)
admin password
- Admin access (HTTP)
Netgear CG814CCR - 2
cusadmin highspeed
- Comcast small business router. Default access at 10.1.10.1
- Admin access (Multi)
Netgear Dg834
n/a admin
- Admin access (Multi)
Netgear Dg834g
admin password
- it should be work also with dg834gt
- Admin access (HTTP)
Netgear DG834GT - 192.168.0.1
admin Password
- Admin access (Multi)
Netgear DM602
admin password
- Admin access (FTP Telnet and HTTP)
Netgear FM114P
n/a (none)
- Admin access (Multi)
Netgear FR114P
admin password
- Admin access (HTTP)
Netgear FSM7326P 24+2 L3 MANAGED PoE Switch
admin (none)
- Admin access (HTTP)
Netgear FVS114 - GR
admin password
- Admin access (HTTP)
Netgear FVS318
admin password
- Admin access (HTTP)
Netgear FWG114P
n/a admin
- password access (Multi)
Netgear GS724t - V1.0.1_1104
n/a password
- Admin access (HTTP)
Netgear GSM7224
admin (none)
- Admin access (HTTP)
Netgear ME102
(none) private
- Standard IP-Address is 192.168.0.5
- Admin access (SNMP)
Netgear MR-314 - 3.26
admin 1234
- Admin access (HTTP)
Netgear MR314
admin 1234
- Admin access (Multi)
Netgear MR814
admin password
- Admin access (HTTP)
Netgear RM356 - None
(none) 1234
- shutdown the router via internet
- Admin access (Telnet)
Netgear RO318
admin 1234
- Admin access (Multi)
Netgear Router/Modem
admin password
- Admin access (Multi)
Netgear RP114 - 3.20-3.26
admin 1234
- default http://192.168.0.1
- Admin access (HTTP)
Netgear RP114 - 3.26
(none) 1234
- telnet 192.168.0.1
- Admin access (Telnet)
Netgear RP614
admin password
- Admin access (HTTP)
Netgear RT314
admin admin
- Admin access (HTTP)
Netgear Sc101
admin password
- Admin access (management software)
Netgear WG602 - 1.7.x
admin password
- Default IP: DHCP or 192.168.0.227
- Admin access (HTTP)
Netgear WG602 - Firmware Version 1.04.0
super 5777364
- Admin access (HTTP)
Netgear WG602 - Firmware Version 1.5.67
super 5777364
- Admin access (HTTP)
Netgear WG602 - Firmware Version 1.7.14
superman 21241036
- Admin access (HTTP)
Netgear WGR614 - v4
admin password
- 192.168.0.1 OR www.routerlogin.net
- Admin access (Multi)
Netgear WGR614 - v6
admin draadloos
- Dutch routers
- Admin access (HTTP)
Netgear WGT624
Gearguy Geardog
- Admin access (Serial console)
Netgear WGT624 - 2
admin password
- Admin access (HTTP)
Netgear WGT634U
admin password
- Admin access (HTTP)
Netgear Wifi Router - WGT 624 v3
admin password
- slawcio26
- Admin access (HTTP)
NETGEAR
Introduction
This Quick Tip lists the default username and password used to login to the web management console (and telnet console where supported) on all current models of Netgear routers.
The defaults are set when the router is shipped from the factory, and if the configuration is later reset.
For security reasons, we recommend that you change the password on your router. However if you do change your password, be sure to remember it or record it somewhere safe.
[It is not possible to change the default username]
If you lose the password, you will need to reset the router configuration (and lose all other configuration settings as well) to be able to login to the router.
This Quick Tip lists the default username and password used to login to the web management console (and telnet console where supported) on all current models of Netgear routers.
The defaults are set when the router is shipped from the factory, and if the configuration is later reset.
For security reasons, we recommend that you change the password on your router. However if you do change your password, be sure to remember it or record it somewhere safe.
[It is not possible to change the default username]
If you lose the password, you will need to reset the router configuration (and lose all other configuration settings as well) to be able to login to the router.
Friday, January 23, 2009
Single-Pair High-speed Digital Subscriber Line
Single-pair High-speed Digital Subscriber Line (SHDSL) is a form of DSL, a data communications technology that enables faster data transmission over copper telephone lines than a conventional voiceband modem can provide. Compared to ADSL, SHDSL employs frequencies that include those used by traditional POTS telephone services to provide equal transmit and receive (i.e. symmetric) data rates. As such, a frequency splitter, or microfilter, can not be used to allow a telephone line to be shared by both an SHDSL service and a POTS service at the same time. Support of symmetric data rates has made SHDSL a popular choice by businesses for PBX, VPN, web hosting and other data services.
SHDSL features symmetrical data rates from 192 kbit/s to 2,304 kbit/s of payload in 64 kbit/s increments for one pair and 384 kbit/s to 4,608 kbit/s in 128 kbit/s increments for two pair applications. The reach varies according to the loop rate and noise conditions (more noise or higher rate means decreased reach) and may be up to 3,000 meters. The two pair feature may alternatively be used for increased reach applications by keeping the data rate low. Halving the data rate per pair will provide similar speeds to single pair lines while increasing the error/noise tolerance.
An optional extended SHDSL mode allows symmetric data rates up to 5696 kbit/s on one pair. Higher data rates may be achieved using two or up to four copper pairs.
SHDSL features symmetrical data rates from 192 kbit/s to 2,304 kbit/s of payload in 64 kbit/s increments for one pair and 384 kbit/s to 4,608 kbit/s in 128 kbit/s increments for two pair applications. The reach varies according to the loop rate and noise conditions (more noise or higher rate means decreased reach) and may be up to 3,000 meters. The two pair feature may alternatively be used for increased reach applications by keeping the data rate low. Halving the data rate per pair will provide similar speeds to single pair lines while increasing the error/noise tolerance.
An optional extended SHDSL mode allows symmetric data rates up to 5696 kbit/s on one pair. Higher data rates may be achieved using two or up to four copper pairs.
Wireless ISP
This typically employs the current low-cost 802.11 Wi-Fi radio systems to link up remote locations over great distances, but can use other higher-power radio communications systems as well.
Traditional 802.11b was licensed for omnidirectional service spanning only 100-150 meters (300-500 ft). 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 silos, very tall trees, or whatever other tall objects are available. There are currently a number of companies that provide this service. A wireless Internet access provider map for USA is publicly available for WISPS.
Traditional 802.11b was licensed for omnidirectional service spanning only 100-150 meters (300-500 ft). 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 silos, very tall trees, or whatever other tall objects are available. There are currently a number of companies that provide this service. A wireless Internet access provider map for USA is publicly available for WISPS.
Satellite Internet
This employs a satellite in geostationary orbit to relay data from the satellite company to each customer. Satellite Internet is usually among the most expensive ways of gaining broadband Internet access, but in rural areas it may only compete with cellular broadband. However, costs have been coming down in recent years to the point that it is becoming more competitive with other broadband options. German ISP, Filiago, offers the ASTRA2Connect satellite Internet system for €320 (equipment) plus €100 (registration) and a flat rate monthly fee dependent on bandwidth - from €20 for 256Kbit/s download, 64Kbits/s upload, to €80 for 2048Kbit/s download, 128Kbits/s upload.[6]
Satellite Internet also has a high latency problem caused by the signal having to travel 35,000 km (22,000 miles) out into space to the satellite and back to Earth again. The signal delay can be as much as 500 milliseconds to 900 milliseconds, which makes this service unsuitable for applications requiring real-time user input such as certain multiplayer Internet games and first-person shooters played over the connection. Despite this, it is still possible for many games to be played, but the scope is limited to real-time strategy or turn-based games. The functionality of live interactive access to a distant computer can also be subject to the problems caused by high latency. These problems are more than tolerable for just basic email access and web browsing and in most cases are barely noticeable.
There is no simple way to get around this problem. The delay is primarily due to the speed of light being 300,000 km/second (186,000 miles per second). Even if all other signaling 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 70,000 km (44,000 miles) to travel from the user to the satellite company.
Since the satellite is usually being used for two-way communications, the total distance increases to 140,000 km (88,000 miles), 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 dial-up modem users' experience, at typically only 150-200 ms total latency.
Most satellite Internet providers also have a FAP (Fair Access Policy). Perhaps one of the largest disadvantages of satellite Internet, these FAPs usually throttle a user's throughput to dial-up data rates after a certain "invisible wall" is hit (usually around 200 MB a day). This FAP usually lasts for 24 hours after the wall is hit, and a user's throughput is restored to whatever tier they paid for. This makes bandwidth-intensive activities nearly impossible to complete in a reasonable amount of time (examples include P2P and newsgroup binary downloading).
The European ASTRA2Connect system has a FAP based on a monthly limit of 2Gbyte of data downloaded, with download data rates reduced for the remainder of the month if the limit is exceeded.
Satellite Internet also has a high latency problem caused by the signal having to travel 35,000 km (22,000 miles) out into space to the satellite and back to Earth again. The signal delay can be as much as 500 milliseconds to 900 milliseconds, which makes this service unsuitable for applications requiring real-time user input such as certain multiplayer Internet games and first-person shooters played over the connection. Despite this, it is still possible for many games to be played, but the scope is limited to real-time strategy or turn-based games. The functionality of live interactive access to a distant computer can also be subject to the problems caused by high latency. These problems are more than tolerable for just basic email access and web browsing and in most cases are barely noticeable.
There is no simple way to get around this problem. The delay is primarily due to the speed of light being 300,000 km/second (186,000 miles per second). Even if all other signaling 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 70,000 km (44,000 miles) to travel from the user to the satellite company.
Since the satellite is usually being used for two-way communications, the total distance increases to 140,000 km (88,000 miles), 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 dial-up modem users' experience, at typically only 150-200 ms total latency.
Most satellite Internet providers also have a FAP (Fair Access Policy). Perhaps one of the largest disadvantages of satellite Internet, these FAPs usually throttle a user's throughput to dial-up data rates after a certain "invisible wall" is hit (usually around 200 MB a day). This FAP usually lasts for 24 hours after the wall is hit, and a user's throughput is restored to whatever tier they paid for. This makes bandwidth-intensive activities nearly impossible to complete in a reasonable amount of time (examples include P2P and newsgroup binary downloading).
The European ASTRA2Connect system has a FAP based on a monthly limit of 2Gbyte of data downloaded, with download data rates reduced for the remainder of the month if the limit is exceeded.
ISDN
Integrated Service Digital Network (ISDN) is one of the oldest broadband digital access methods for consumers and businesses to connect to the Internet. It is a telephone data service standard. Its use in the United States peaked in the late 1990s prior to the availability of DSL and cable modem technologies. Broadband service is usually compared to ISDN-BRI because this was the standard broadband access technology that formed a baseline for the challenges faced by the early broadband providers. These providers sought to compete against ISDN by offering faster and cheaper services to consumers.
A basic rate ISDN line (known as ISDN-BRI) is an ISDN line with 2 data "bearer" channels (DS0 - 64 kbit/s each). Using ISDN terminal adapters (erroneously called modems), it is possible to bond together 2 or more separate ISDN-BRI lines to reach bandwidths of 256 kbit/s or more. The ISDN channel bonding technology has been used for video conference applications and broadband data transmission.
Primary rate ISDN, known as ISDN-PRI, is an ISDN line with 23 DS0 channels and total bandwidth of 1,544 kbit/s (US standard). ISDN E1 (European standard) line is an ISDN lines with 30 DS0 channels and total bandwidth of 2,048 kbit/s. Because ISDN is a telephone-based product, a lot of the terminology and physical aspects of the line are shared by the ISDN-PRI used for voice services. An ISDN line can therefore be "provisioned" for voice or data and many different options, depending on the equipment being used at any particular installation, and depending on the offerings of the telephone company's central office switch. Most ISDN-PRI's are used for telephone voice communication using large PBX systems, rather than for data. One obvious exception is that ISPs usually have ISDN-PRI's for handling ISDN data and modem calls.
It is mainly of historical interest that many of the earlier ISDN data lines used 56 kbit/s rather than 64 kbit/s "B" channels of data. This caused ISDN-BRI to be offered at both 128 kbit/s and 112 kbit/s rates, depending on the central office's switching equipment.
A basic rate ISDN line (known as ISDN-BRI) is an ISDN line with 2 data "bearer" channels (DS0 - 64 kbit/s each). Using ISDN terminal adapters (erroneously called modems), it is possible to bond together 2 or more separate ISDN-BRI lines to reach bandwidths of 256 kbit/s or more. The ISDN channel bonding technology has been used for video conference applications and broadband data transmission.
Primary rate ISDN, known as ISDN-PRI, is an ISDN line with 23 DS0 channels and total bandwidth of 1,544 kbit/s (US standard). ISDN E1 (European standard) line is an ISDN lines with 30 DS0 channels and total bandwidth of 2,048 kbit/s. Because ISDN is a telephone-based product, a lot of the terminology and physical aspects of the line are shared by the ISDN-PRI used for voice services. An ISDN line can therefore be "provisioned" for voice or data and many different options, depending on the equipment being used at any particular installation, and depending on the offerings of the telephone company's central office switch. Most ISDN-PRI's are used for telephone voice communication using large PBX systems, rather than for data. One obvious exception is that ISPs usually have ISDN-PRI's for handling ISDN data and modem calls.
It is mainly of historical interest that many of the earlier ISDN data lines used 56 kbit/s rather than 64 kbit/s "B" channels of data. This caused ISDN-BRI to be offered at both 128 kbit/s and 112 kbit/s rates, depending on the central office's switching equipment.
Broadband Internet access
Broadband Internet access, often shortened to just broadband, is high data rate Internet access—typically contrasted with dial-up access over a modem.
Dial-up modems are generally only capable of a maximum bitrate of 56 kbit/s (kilobits per second) and require the full use of a telephone line—whereas broadband technologies supply at least double this bandwidth and generally without disrupting telephone use.
Although various minimum bandwidths have been used in definitions of broadband, ranging up from 64 kbit/s up to 1.0 Mbit/s, the 2006 OECD report [1] is typical by defining broadband as having download data transfer rates equal to or faster than 256 kbit/s, while the United States FCC, as of 2008, defines broadband as anything above 768 kbit/s. [2] [3] The trend is to raise the threshold of the broadband definition as the marketplace rolls out faster services each year.[3]
Data rates are defined in terms of maximum download because several common consumer broadband technologies such as ADSL are "asymmetric"—supporting much slower maximum upload data rate than download.
Dial-up modems are generally only capable of a maximum bitrate of 56 kbit/s (kilobits per second) and require the full use of a telephone line—whereas broadband technologies supply at least double this bandwidth and generally without disrupting telephone use.
Although various minimum bandwidths have been used in definitions of broadband, ranging up from 64 kbit/s up to 1.0 Mbit/s, the 2006 OECD report [1] is typical by defining broadband as having download data transfer rates equal to or faster than 256 kbit/s, while the United States FCC, as of 2008, defines broadband as anything above 768 kbit/s. [2] [3] The trend is to raise the threshold of the broadband definition as the marketplace rolls out faster services each year.[3]
Data rates are defined in terms of maximum download because several common consumer broadband technologies such as ADSL are "asymmetric"—supporting much slower maximum upload data rate than download.
How ADSL works
On the wire
Currently, most ADSL communication is full-duplex. Full-duplex ADSL communication is usually achieved on a wire pair by either frequency-division duplex (FDD), echo-cancelling duplex (ECD), or time-division duplexing (TDD). FDD uses two separate frequency bands, referred to as the upstream and downstream bands. The upstream band is used for communication from the end user to the telephone central office. The downstream band is used for communicating from the central office to the end user.
Frequency plan for ADSL. The red area is the frequency range used by normal voice telephony (PSTN), the green (upstream) and blue (downstream) areas are used for ADSL.
With standard ADSL (annex A), the band from 25.875 kHz to 138 kHz is used for upstream communication, while 138 kHz – 1104 kHz is used for downstream communication. Each of these is further divided into smaller frequency channels of 4.3125 kHz. These frequency channels are sometimes termed bins. During initial training, the ADSL modem tests each of the bins to establish the signal-to-noise ratio at each bin's frequency. The distance from the telephone exchange and the characteristics of the cable mean that some frequencies may not propagate well, and noise on the copper wire, interference from AM radio stations and local interference and electrical noise at the customer end mean that relatively high levels of noise are present at some frequencies, so considering both effects the signal-to-noise ratio in some bins (at some frequencies) may be good or completely inadequate. A bad signal-to-noise ratio measured at certain frequencies will mean that those bins will not be used, resulting in a reduced maximum link capacity but with an otherwise functional ADSL connection.
The DSL modem will make a plan on how to exploit each of the bins sometimes termed "bits per bin" allocation. Those bins that have a good signal-to-noise ratio (SNR) will be chosen to transmit signals chosen from a greater number of possible encoded values (this range of possibilities equating to more bits of data sent) in each main clock cycle. This number must of possibilities must not be so large that the receiver might mishear which one was intended in the presence of noise. Noisy bins may only be required to carry as few as two bits, a choice from only one of four possible patterns, or only one bit per bin in the case of ADSL2+, and really noisy bins are not used at all. If the pattern of noise versus frequencies heard in the bins changes, the DSL modem can alter the bits-per-bin allocations, in a process called "bitswap", where bins that have become more noisy are only required to carry fewer bits and other channels will be chosen to be given a higher burden. The data transfer capacity the DSL modem therefore reports is determined by the total of the bits-per-bin allocations of all the bins combined. Lower signal-to-noise ratios and more bins being in use gives a higher total link capacity, higher signal-to-noise ratios or fewer bins being used gives a low link capacity.
The total maximum capacity derived from summing the bits-per-bins is reported by DSL modems and is sometimes termed sync rate. This will always be rather misleading as the true maximum link capacity for user data transfer rate will be significantly lower because extra data is transmitted that is termed protocol overhead, a reduced figure of around 84-87% at most for PPPoA connnections being a common example. In addition some ISPs will have traffic policies that limit maximum transfer rates further in the networks beyond the exchange, and traffic congestion on the Internet, heavy loading on servers and slowness or inefficiency in customers' computers may all contribute to reductions below the maximum attainable.
The choices the DSL modem make can also be either conservative, where the modem chooses to allocate fewer bits per bin than it possible could, a choice which makes for a slower connection, or less conservative in which more bits per bin are chosen in which case there is a greater risk case of error should future signal-to-noise ratios deteriorate to the point where the bits-per-bin allocations chosen are too high to cope with the greater noise present. This conservatism involving a choice to using fewer bits per bin as a safeguard against future noise increases is reported as the signal-to-noise ratio margin or SNR margin. The telephone exchange can indicate a suggested SNR margin to the customer's DSL modem when it initially connects, and the modem may make its bits-per-bin allocation plan accordingly. A high SNR margin will mean a reduced maximum throughput but possibly greater reliability. A low SNR margin will mean high speeds provided the noise level does not increase too much, otherwise the connection will have to be dropped and renegotiated. ADSL2+ can better accommodate such circumstances, offering a feature termed seamless rate adaptation (SRA), which can accomodate changes in total link capacity with less disruption to communications.
Vendors may support usage of higher frequencies as a proprietary extension to the standard. However, this requires matching vendor-supplied equipment on both ends of the line, and will likely result in crosstalk problems that affect other lines in the same bundle.
There is a direct relationship between the number of channels available and the throughput capacity of the ADSL connection. The exact data capacity per channel depends on the modulation method used.
Installation issues
Due to the way it uses the frequency spectrum, ADSL deployment presents some issues. It is necessary to install appropriate frequency filters at the customer's premises, to avoid interferences with the voice service, while at the same time taking care to keep a clean signal level for the ADSL connection.
In the early days of DSL, installation required a technician to visit the premises. A splitter or microfilter was installed near the demarcation point, from which a dedicated data line was installed. This way, the DSL signal is separated earlier and is not attenuated inside the customer premises. However, this procedure is costly, and also caused problems with customers complaining about having to wait for the technician to perform the installation. As a result, many DSL vendors started offering a self-install option, in which they ship equipment and instructions to the customer. Instead of separating the DSL signal at the demarcation point, the opposite is done: the DSL signal is filtered at each phone outlet by use of a low-pass filter for voice and a high-pass filter for data, usually enclosed in what is known as a microfilter. This microfilter can be plugged directly into any phone jack, and does not require any rewiring at the customer's premises.
A side effect of the move to the self-install model is that the DSL signal can be degraded, especially if more than 5 voiceband devices are connected to the line. The DSL signal is now present on all telephone wiring in the building, causing attenuation and echo. A way to circumvent this is to go back to the original model, and install one filter upstream from all telephone jacks in the building, except for the jack to which the DSL modem will be connected. Since this requires wiring changes by the customer and may not work on some household telephone wiring, it is rarely done. It is usually much easier to install filters at each telephone jack that is in use.
DSL signals may be degraded by older telephone line surge protectors, poorly designed microfilters and by long telephone extension cords. Telephone extension cords are typically made with small-gauge braided copper conductors, which are more susceptible to electromagnetic interference and have more attenuation than single-strand copper wires typically wired to telephone jacks. Within the customer premises, electrical noise, poor mains quality and radio frequency interference can all pollute the DSL signal, and these effects are especially significant where the customer has a long phone line on which the received signal levels are greatly attenuated, so signal levels are low relative to any local noise that may be introduced. This will have the effect of reducing speeds or even causing unreliable connections.
Currently, most ADSL communication is full-duplex. Full-duplex ADSL communication is usually achieved on a wire pair by either frequency-division duplex (FDD), echo-cancelling duplex (ECD), or time-division duplexing (TDD). FDD uses two separate frequency bands, referred to as the upstream and downstream bands. The upstream band is used for communication from the end user to the telephone central office. The downstream band is used for communicating from the central office to the end user.
Frequency plan for ADSL. The red area is the frequency range used by normal voice telephony (PSTN), the green (upstream) and blue (downstream) areas are used for ADSL.
With standard ADSL (annex A), the band from 25.875 kHz to 138 kHz is used for upstream communication, while 138 kHz – 1104 kHz is used for downstream communication. Each of these is further divided into smaller frequency channels of 4.3125 kHz. These frequency channels are sometimes termed bins. During initial training, the ADSL modem tests each of the bins to establish the signal-to-noise ratio at each bin's frequency. The distance from the telephone exchange and the characteristics of the cable mean that some frequencies may not propagate well, and noise on the copper wire, interference from AM radio stations and local interference and electrical noise at the customer end mean that relatively high levels of noise are present at some frequencies, so considering both effects the signal-to-noise ratio in some bins (at some frequencies) may be good or completely inadequate. A bad signal-to-noise ratio measured at certain frequencies will mean that those bins will not be used, resulting in a reduced maximum link capacity but with an otherwise functional ADSL connection.
The DSL modem will make a plan on how to exploit each of the bins sometimes termed "bits per bin" allocation. Those bins that have a good signal-to-noise ratio (SNR) will be chosen to transmit signals chosen from a greater number of possible encoded values (this range of possibilities equating to more bits of data sent) in each main clock cycle. This number must of possibilities must not be so large that the receiver might mishear which one was intended in the presence of noise. Noisy bins may only be required to carry as few as two bits, a choice from only one of four possible patterns, or only one bit per bin in the case of ADSL2+, and really noisy bins are not used at all. If the pattern of noise versus frequencies heard in the bins changes, the DSL modem can alter the bits-per-bin allocations, in a process called "bitswap", where bins that have become more noisy are only required to carry fewer bits and other channels will be chosen to be given a higher burden. The data transfer capacity the DSL modem therefore reports is determined by the total of the bits-per-bin allocations of all the bins combined. Lower signal-to-noise ratios and more bins being in use gives a higher total link capacity, higher signal-to-noise ratios or fewer bins being used gives a low link capacity.
The total maximum capacity derived from summing the bits-per-bins is reported by DSL modems and is sometimes termed sync rate. This will always be rather misleading as the true maximum link capacity for user data transfer rate will be significantly lower because extra data is transmitted that is termed protocol overhead, a reduced figure of around 84-87% at most for PPPoA connnections being a common example. In addition some ISPs will have traffic policies that limit maximum transfer rates further in the networks beyond the exchange, and traffic congestion on the Internet, heavy loading on servers and slowness or inefficiency in customers' computers may all contribute to reductions below the maximum attainable.
The choices the DSL modem make can also be either conservative, where the modem chooses to allocate fewer bits per bin than it possible could, a choice which makes for a slower connection, or less conservative in which more bits per bin are chosen in which case there is a greater risk case of error should future signal-to-noise ratios deteriorate to the point where the bits-per-bin allocations chosen are too high to cope with the greater noise present. This conservatism involving a choice to using fewer bits per bin as a safeguard against future noise increases is reported as the signal-to-noise ratio margin or SNR margin. The telephone exchange can indicate a suggested SNR margin to the customer's DSL modem when it initially connects, and the modem may make its bits-per-bin allocation plan accordingly. A high SNR margin will mean a reduced maximum throughput but possibly greater reliability. A low SNR margin will mean high speeds provided the noise level does not increase too much, otherwise the connection will have to be dropped and renegotiated. ADSL2+ can better accommodate such circumstances, offering a feature termed seamless rate adaptation (SRA), which can accomodate changes in total link capacity with less disruption to communications.
Vendors may support usage of higher frequencies as a proprietary extension to the standard. However, this requires matching vendor-supplied equipment on both ends of the line, and will likely result in crosstalk problems that affect other lines in the same bundle.
There is a direct relationship between the number of channels available and the throughput capacity of the ADSL connection. The exact data capacity per channel depends on the modulation method used.
Installation issues
Due to the way it uses the frequency spectrum, ADSL deployment presents some issues. It is necessary to install appropriate frequency filters at the customer's premises, to avoid interferences with the voice service, while at the same time taking care to keep a clean signal level for the ADSL connection.
In the early days of DSL, installation required a technician to visit the premises. A splitter or microfilter was installed near the demarcation point, from which a dedicated data line was installed. This way, the DSL signal is separated earlier and is not attenuated inside the customer premises. However, this procedure is costly, and also caused problems with customers complaining about having to wait for the technician to perform the installation. As a result, many DSL vendors started offering a self-install option, in which they ship equipment and instructions to the customer. Instead of separating the DSL signal at the demarcation point, the opposite is done: the DSL signal is filtered at each phone outlet by use of a low-pass filter for voice and a high-pass filter for data, usually enclosed in what is known as a microfilter. This microfilter can be plugged directly into any phone jack, and does not require any rewiring at the customer's premises.
A side effect of the move to the self-install model is that the DSL signal can be degraded, especially if more than 5 voiceband devices are connected to the line. The DSL signal is now present on all telephone wiring in the building, causing attenuation and echo. A way to circumvent this is to go back to the original model, and install one filter upstream from all telephone jacks in the building, except for the jack to which the DSL modem will be connected. Since this requires wiring changes by the customer and may not work on some household telephone wiring, it is rarely done. It is usually much easier to install filters at each telephone jack that is in use.
DSL signals may be degraded by older telephone line surge protectors, poorly designed microfilters and by long telephone extension cords. Telephone extension cords are typically made with small-gauge braided copper conductors, which are more susceptible to electromagnetic interference and have more attenuation than single-strand copper wires typically wired to telephone jacks. Within the customer premises, electrical noise, poor mains quality and radio frequency interference can all pollute the DSL signal, and these effects are especially significant where the customer has a long phone line on which the received signal levels are greatly attenuated, so signal levels are low relative to any local noise that may be introduced. This will have the effect of reducing speeds or even causing unreliable connections.
Asymmetric Digital Subscriber Line
Asymmetric Digital Subscriber Line (ADSL) is a form of DSL, a data communications technology that enables faster data transmission over copper telephone lines than a conventional voiceband modem can provide. It does this by utilizing frequencies that are not used by a voice telephone call. A splitter - or microfilter - allows a single telephone connection to be used for both ADSL service and voice calls at the same time. Because phone lines vary in quality and were not originally engineered with DSL in mind, it can generally only be used over short distances, typically less than 4km
Digital subscriber line access multiplexer
A Digital Subscriber Line Access Multiplexer (DSLAM, often pronounced dee-slam) allows telephone lines to make faster connections to the Internet. It is a network device, located in the telephony exchanges of the service providers, that connects multiple customer Digital Subscriber Lines (DSLs) to a high-speed Internet backbone line using multiplexing techniques. By placing remote DSLAMs at locations remote to the telephone company central office (CO), telephone companies provide DSL service to locations previously beyond effective range.
* DSL modems vary in data speed from hundreds of kilobits per second to many megabits, while voiceband modems are nominally 56K modems and actually limited to approximately 50 kb/s.
* DSL modems exchange data with only the DSLAM to which they are wired, which in turn connects them to the Internet, while most voiceband modems can dial directly anywhere in the world.
* DSL modems are intended for particular protocols and sometimes won't work on another line even from the same company, while most voiceband modems use international standards and can "fall back" to find a standard that will work.[citation needed]
Most of these differences are of little interest to consumers, except the greater speed of DSL and the ability to use the telephone even when the computer is online.
Because a single phone line commonly carries DSL and voice, DSL filters are used to separate the two uses.
* DSL modems vary in data speed from hundreds of kilobits per second to many megabits, while voiceband modems are nominally 56K modems and actually limited to approximately 50 kb/s.
* DSL modems exchange data with only the DSLAM to which they are wired, which in turn connects them to the Internet, while most voiceband modems can dial directly anywhere in the world.
* DSL modems are intended for particular protocols and sometimes won't work on another line even from the same company, while most voiceband modems use international standards and can "fall back" to find a standard that will work.[citation needed]
Most of these differences are of little interest to consumers, except the greater speed of DSL and the ability to use the telephone even when the computer is online.
Because a single phone line commonly carries DSL and voice, DSL filters are used to separate the two uses.
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