different problems in dial-up connections...

Dial-up requires no additional infrastructure on top of the telephone network. As telephone points are available throughout the world, dial-up remains useful to travelers. Dial-up is usually the only choice available for most rural or remote areas where getting a broadband connection is impossible due to low population and demand. Sometimes dial-up access may also be an alternative to people who have limited budgets as it is offered for free by some, though broadband is now increasingly available at lower prices in countries such as the United States, Canada, Hong Kong, Australia and the United Kingdom due to market competition.

Dial-up requires time to establish a telephone connection (several seconds, depending on the location) and perform handshaking before data transfers can take place. In locales with telephone connection charges, each connection incurs an incremental cost. If calls are time-charged, the duration of the connection incurs costs.

Dial-up access is a transient connection, because either the user or the ISP terminates the connection. Internet service providers will often set a limit on connection durations to prevent hogging of access, and will disconnect the user — requiring reconnection and the costs and delays associated with it.

In recent years, the availability of dialup access numbers has been shrinking. Most notably in part due to consolidations within the primary U.S. modem network operators such as MCI, Qwest, Sprint, and Level3, who have refocused their attention to broadband Internet access services.

dial-up errors..

Common Problems and Errors

Most problems with connecting are do to a configuration error. The easiest way to fix this issue it to rebuild the dial-up connection. This save time and confusion in checking the many settings involved, as the default Windows and Mac settings will work with our network. For Windows users, see “Rebuilding you Dial-up connection, below. Mac users should check their settings (see setup instructions for your particular Mac. )

Error 691
A 691 error indicates that your username or password is incorrect. Retype both your username and password for the dial-up connection. With Windows XP it is usually best to rebuild the connection, and if checking the username and password does not work, try rebuilding your connection. (See Below)

Error 678
Error 678 can be an issue with your drivers, but many times it can be that the computer is dialing the wrong number. Check the number that the computer is dialing, or rebuild the connection.

Error 680
Error 680 indicates that the modem is not hearing a dial tone. Try checking the connection, making sure that the phone cord is connected to the wall jack and into the computer with no splitters, surge protectors, or filters of any kind. The phone cord should be plugged into the jack on the back of the computer that usually is labeled “line.” You can also test the wall jack by plugging a phone into it and listening for a dial tone. If you hear a dial tone, it is likely, especially if you have had thunder storms in your area recently, that there is something wrong with the modem.

Error 676
Error 676 indicates that the line is busy. Usually this like 678 indicates that you might be dialing the wrong number. Check the number that the computer is dialing, or rebuild the connection. This error can also occur if you have voice-mail. If you have voice mail try adding two comas in front of the phone number to have the modem wait till the “stutter” tone is finished.

Rebuilding your Dial-up connection

Mac users do not need, or are able to “rebuild” their connection. For Windows users, the easiest way to rebuild your connection is to open up Internet Explorer, go to “Tools” on the top, and select “Internet Options.” This will bring you to the Internet Options window. On the top you will see several “Tabs”, click on the one labeled “Connection.”

To remove the dial-up connection, click on the name of the connection in the dial-up box. Once it is highlighted, click on the “Remove button.” Once the connection has been removed you can click on the “Setup” button and follow along with the New Connection Wizard, or follow the setup procedure with “Inetwiz.”

For Advanced users, you can go to http://modemhelp.org, for more information on troubleshooting dial-up connection problems.

List of Windows DUN error codes.

• 600 An operation is pending.
• 601 The port handle is invalid.
• 602 The port is already open.
• 603 Caller's buffer is too small.
• 604 Wrong information specified.
• 605 Cannot set port information.
• 606 The port is not connected.
• 607 The event is invalid.
• 608 The device does not exist.
• 609 The device type does not exist.
• 610 The buffer is invalid.
• 611 The route is not available.
• 612 The route is not allocated.
• 613 Invalid compression specified.
• 614 Out of buffers.
• 615 The port was not found.
• 616 An asynchronous request is pending.
• 617 The port or device is already disconnecting.
• 618 The port is not open.
• 619 The port is disconnected.
• 620 There are no endpoints.
• 621 Cannot open the phone book file.
• 622 Cannot load the phone book file.
• 623 Cannot find the phone book entry.
• 624 Cannot write the phone book file.
• 625 Invalid information found in the phone book.
• 626 Cannot load a string.
• 627 Cannot find key.
• 628 The port was disconnected.
• 629 The port was disconnected by the remote machine.
• 630 The port was disconnected due to hardware failure.
• 631 The port was disconnected by the user.
• 632 The structure size is incorrect.
• 633 The port is already in use or is not configured for Remote Access dialout.
• 634 Cannot register your computer on the remote network.
• 635 Unknown error.
• 636 The wrong device is attached to the port.
• 637 The string could not be converted.
• 638 The request has timed out.
• 639 No asynchronous net available.
• 640 A NetBIOS error has occurred.
• 641 The server cannot allocate NetBIOS resources needed to support the client.
• 642 One of your NetBIOS names is already registered on the remote network.
• 643 A network adapter at the server failed.
• 644 You will not receive network message popups.
• 645 Internal authentication error.
• 646 The account is not permitted to log on at this time of day.
• 647 The account is disabled.
• 648 The password has expired.
• 649 The account does not have Remote Access permission.
• 650 The Remote Access server is not responding.
• 651 Your modem (or other connecting device) has reported an error.
• 652 Unrecognized response from the device.
• 653 A macro required by the device was not found in the device .INF file section.
• 654 A command or response in the device .INF file section refers to an undefined macro
• 655 The macro was not found in the device .INF file section.
• 656 The macro in the device .INF file section contains an undefined macro
• 657 The device .INF file could not be opened.
• 658 The device name in the device .INF or media .INI file is too long.
• 659 The media .INI file refers to an unknown device name.
• 660 The device .INF file contains no responses for the command.
• 661 The device .INF file is missing a command.
• 662 Attempted to set a macro not listed in device .INF file section.
• 663 The media .INI file refers to an unknown device type.
• 664 Cannot allocate memory.
• 665 The port is not configured for Remote Access.
• 666 Your modem (or other connecting device) is not functioning.
• 667 Cannot read the media .INI file.
• 668 The connection dropped.
• 669 The usage parameter in the media .INI file is invalid.
• 670 Cannot read the section name from the media .INI file.
• 671 Cannot read the device type from the media .INI file.
• 672 Cannot read the device name from the media .INI file.
• 673 Cannot read the usage from the media .INI file.
• 674 Cannot read the maximum connection BPS rate from the media .INI file.
• 675 Cannot read the maximum carrier BPS rate from the media .INI file.
• 676 The line is busy.
• 677 A person answered instead of a modem.
• 678 There is no answer.
• 679 Cannot detect carrier.
• 680 There is no dial tone.
• 681 General error reported by device.
• 682 ERROR WRITING SECTIONNAME
• 683 ERROR WRITING DEVICETYPE
• 684 ERROR WRITING DEVICENAME
• 685 ERROR WRITING MAXCONNECTBPS
• 686 ERROR WRITING MAXCARRIERBPS
• 687 ERROR WRITING USAGE
• 688 ERROR WRITING DEFAULTOFF
• 689 ERROR READING DEFAULTOFF
• 690 ERROR EMPTY INI FILE
• 691 Access denied because username and/or password is invalid on the domain.
• 692 Hardware failure in port or attached device.
• 693 ERROR NOT BINARY MACRO
• 694 ERROR DCB NOT FOUND
• 695 ERROR STATE MACHINES NOT STARTED
• 696 ERROR STATE MACHINES ALREADY STARTED
• 697 ERROR PARTIAL RESPONSE LOOPING
• 698 A response keyname in the device .INF file is not in the expected format.
• 699 The device response caused buffer overflow.
• 700 The expanded command in the device .INF file is too long.
• 701 The device moved to a BPS rate not supported by the COM driver.
• 702 Device response received when none expected.
• 703 ERROR INTERACTIVE MODE
• 704 ERROR BAD CALLBACK NUMBER
• 705 ERROR INVALID AUTH STATE
• 706 ERROR WRITING INITBPS
• 707 X.25 diagnostic indication.
• 708 The account has expired.
• 709 Error changing password on domain.
• 710 Serial overrun errors were detected while communicating with your modem.
• 711 RasMan initialization failure. Check the event log.
• 712 Biplex port is initializing. Wait a few seconds and redial.
• 713 No active ISDN lines are available.
• 714 Not enough ISDN channels are available to make the call.
• 715 Too many errors occurred because of poor phone line quality.
• 716 The Remote Access IP configuration is unusable.
• 717 No IP addresses are available in the static pool of Remote Access IP addresses.
• 718 PPP timeout.
• 719 PPP terminated by remote machine.
• 720 No PPP control protocols configured.
• 721 Remote PPP peer is not responding.
• 722 The PPP packet is invalid.
• 723 The phone number including prefix and suffix is too long.
• 724 The IPX protocol cannot dial-out on the port because the computer is an IPX router.
• 725 The IPX protocol cannot dial-in on the port because the IPX router is not installed..
• 726 The IPX protocol cannot be used for dial-out on more than one port at a time.
• 727 Cannot access TCPCFG.DLL.
• 728 Cannot find an IP adapter bound to Remote Access.
• 729 SLIP cannot be used unless the IP protocol is installed.
• 730 Computer registration is not complete.
• 731 The protocol is not configured.
• 732 The PPP negotiation is not converging.
• 733 The PPP control protocol for this network protocol is not available on the server.
• 734 The PPP link control protocol terminated..
• 735 The requested address was rejected by the server..
• 736 The remote computer terminated the control protocol.
• 737 Loopback detected..
• 738 The server did not assign an address.
• 739 The remote server cannot use the Windows NT encrypted password.
• 740 The TAPI devices configured for Remote Access failed to initialize or were not installed correctly.
• 741 The local computer does not support encryption.
• 742 The remote server does not support encryption.
• 743 The remote server requires encryption.
• 744 Cannot use the IPX net number assigned by the remote server. Check the event log.
• 752 A syntax error was encountered while processing a script.

what is wi-fi?

Wi-Fi (pronounced wye-fye, IPA: /ˈwaɪfaɪ/) is a wireless technology brand owned by the Wi-Fi Alliance intended to improve the interoperability of wireless local area network products based on the IEEE 802.11 standards. Common applications for Wi-Fi include Internet and VoIP phone access, gaming, and network connectivity for consumer electronics such as televisions, DVD players, and digital cameras.

The Wi-Fi Alliance is a consortium of separate and independent companies agreeing to a set of common interoperable products based on the family of IEEE 802.11 standards.^[1] The Wi-Fi Alliance certifies products via a set of established test procedures to establish interoperability. Those manufacturers that are members of Wi-Fi Alliance whose products pass these interoperability tests can mark their products and product packaging with the Wi-Fi logo.^[2]

Wi-Fi technologies have gone through several generations since their inception in 1997. Wi-Fi is supported to different extents under Microsoft Windows, Apple Mac OS X and open source UnixLinux operating systems. and

what is isdn fiber optic?

SDN (Integrated Services Digital Network) is a set of CCITT/ITU standards for digital transmission over ordinary telephone copper wire as well as over other media.

There are two levels of service: the Basic Rate Interface (BRI), intended for the home and small enterprise, and the Primary Rate Interface ( PRI), for larger users. Both rates include a number of B-channels and a D-channels. Each B-channel carries data, voice, and other services. Each D-channel carries control and signaling information.

The Basic Rate Interface consists of two 64 Kbps B-channels and one 16 Kbps D- channel. Thus, a Basic Rate user can have up to 128 Kbps service. The Primary Rate consists of 23 B-channels and one 64 Kpbs D-channel in the United States or 30 B-channels and 1 D-channel in Europe.

ISDN in concept is the integration of both analog or voice data together with digital data over the same network. Although the ISDN you can install is integrating these on a medium designed for analog transmission, broadband ISDN (BISDN) is intended to extend the integration of both services throughout the rest of the end-to-end path using fiber optic.

The signalingpart of the ISDN networks is the SS7 - ISUP signalling.

what is dsl?

Digital Subscriber Line (DSL) service is one of the most exciting technologies to come to market in the area of information access. The concept is as elegant as it is simple - DSL achieves broadband speeds over ordinary phone lines. That elegance and simplicity has attracted significant attention from a wide variety of customers, and DSL is one of the fastest growing high-speed access technologies for both business and personal use on the market.

Of all of the new telecommunications technologies, DSL is the most powerful, straightforward and flexible solution for high-speed access and information transfer – and the supporting network is already in place. We'll examine DSL and discuss some of its advantages and disadvantages.

What is DSL?

Digital Subscriber Line is a telecommunications service that makes it possible to transform an ordinary phone line into a high-speed conduit for data, voice and video. As long as your home or business is close enough to your service providers central office (a local office with switching equipment which connects everyone in a certain area to the companies net-work), you'll be able to subscribe to DSL service. Typical connections allow users to receive data at 1.5 Mbps and send data at approximately 256 Kbps, though actual speed is determined by the proximity to the providers central office. DSL service is always on – users don't need to dial a connection to gain access to the Internet – and some services even allow users to use the same line for voice and data traffic.

There are a wide array of DSL technologies available, depending on your location and your bandwidth needs. In brief, they are:

• IDSL (ISDN Digital Subscriber Line) is a form of DSL that uses ISDN provisioning and testing, and can coexist with current analog and ISDN services. IDSL is usually limited to 144 Kbps upstream and downstream, but can sometimes provide further reach than other DSL solutions because it does not have the same distance limitations.
• ADSL (Asymmetric Digital Subscriber Line) employs two different transmission speeds, with the downstream speed (from the provider to the user) usually being much higher than the upstream speed (from the user to the corporate host). ADSL can achieve downstream data rates up to 8 Mbps and upstream rates to 1 Mbps.
• VDSL (Very High Speed Digital Subscriber Line) promises even higher speeds than ADSL, although over much shorter distances. Standardization on speeds and technological specifications are currently in progress.
• RADSL (Rate Adaptive Digital Subscriber Line) adjusts the data transmission rate to match the quality of the phone line. RADSL users get the very best performance their telephone line is conditioned to provide, providing transmission rates of up to 7 Mbps downstream and 1 Mbps upstream.
• HDSL/SDSL (High Data Rate Digital Subscriber Line/Symmetric Digital Subscriber Line) utilize two standard phone lines for 1.5 Mbps transmission speeds and offer the capability to combine three phone lines for 2.0 Mbps speeds. HDSL and SDSL are intended as lower cost replacements for dedicated and fractional T-1 lines 2 .

How fast is DSL?

DSL services transfer data at speeds ranging from 128 Kbps (IDSL) to a potential 9.0 Mbps (HDSL) downstream. Up-stream speeds range from 128 Kbps to 1 Mbps and, in some cases, even higher.

What is the future of DSL?

The future of DSL is very bright, as businesses and consumers increasingly move toward an information-based economy. As companies implement more sophisticated applications that require high bandwidth capability, DSL is emerging as the perfect combination of price and performance for a diverse range of applications, from workgroups in different cities across the country to teleworkers in their homes. Today, many service providers are presently offering or implementing one form of DSL technology or another.

Who uses DSL?

DSL is used by a wide variety of companies and individuals who all have one thing in common – the need for reliable, always on high-speed data transmission and access. DSL service is used in the telecommunications industry by network service providers, ISPs, and local and public telephone companies. It is used by universities, hospitals and research facilities where high-speed data transmission is essential. In the business environment, DSL services are used for telework programs, workgroup solutions, companies with campuses, and corporate networks in single and multiple locations on a regional or nationwide basis.

What are the advantages of DSL?

There are many advantages to DSL. The most significant advantage is the fact that DSL is more cost-effective because it eliminates the need for extensive and expensive infrastructure upgrades. DSL service requires no new phone lines and little new equipment. Another advantage that is equally important is DSL’s blazing speed. DSL technology transforms the nearly 700 million phone lines installed worldwide into multi-megabyte data pipes capable of speeding digital video and data to homes and businesses.

Additionally, DSL is :

• Easy to use, and requires no additional training
• Rapidly being deployed and accepted as the emerging standard for high-speed connectivity
• An always on service that does not require unreliable dial up connections
• The fastest solution available for telework programs

DSL solves many of the problems associated with alternate access technologies by using the existing telecommunications system to remove the bottlenecks often associated with the last mile between the network service provider and the users of those services.

What are the disadvantages of DSL?

There are some disadvantages to the use of DSL service. The greatest disadvantage at the present time is availability –because DSL is distance sensitive, availability is determined by the distance from the providers central office. Although DSL service is widely available in most metropolitan areas, is often not available in non-metropolitan or rural areas because the distance sensitivity limitation. Service may be limited to within 18,000 feet of the DSL providers local office, or point of presence, though there are usually several such locations in a given urban area.

Additionally, DSL operates on traditional copper telephone lines, and is incompatible with fiber optic lines.

Summary.

Phone lines are everywhere – and a technology that allows exponentially faster speeds for Internet access and data transfer on ordinary phone lines is truly revolutionary. The timing for DSL couldn't be better. As the Internet continues to evolve into a global online interface supporting multimedia data, audio and video, bandwidth demand will continue to soar and DSL provides the capability to handle that demand.