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Q:
What speeds were there
before 56K?
A: 300 bit per second - 1960s through 1983 or so 1200 bit per second - gained popularity in 1983 - 1985 2400 bit per second - arrived early 1985 9600 bit per second - US Robotics 9600 intro Comdex, 1986 14.4K bit per second - 19.2K bit per second - 28.8K bit per second - 1994 33.6K bit per second - 56K bit per second - became the standard in 1998
Q: Can I get dialup? A: Most people can get dial-up. To get dial-up you need a phone line and an ISP.
Q: What hardware do I need to use dialup? A: A modem. You purchase a modem for $15-100 depending on features and types. Most, if not all computers bought today come with 56K modems standard. If your low on power outlets,
go with an internal PCI based modem(56K). Otherwise buy an external modem,
for they are much easier to troubleshoot when problems arise! Also, you
won't need to power cycle (reboot) your PC when you do need to reset the
modem which must be done with all internal modems usually.
Q: How long does it take to dial-up? A: It usually takes between 7-30 seconds to connect with a V90 (56K) modem.
Q: What do dialup modems look like? A: These are the main types of modems:
Q:
What is needed to establish
a V.90 transmission?
A: Digital connection from server to the phone network: This means that the connection on one end must terminate at a digital circuit. If your PoP supports x2 currently, this condition is met. V.90 support is required
on both ends: Not only does your PoP need to be capable of V.90 connections,
but your modem must also support the V.90 code.
ONE analog-to-digital conversion
process: For the V.90 technology to work, there can be a maximum of one
analog-to-digital conversion process that takes place between your analog
modem and the digital modem on your ISP's side. This is where you may
experience a problem. While many telephone companies are updating their
equipment, not all areas meet this condition.
A: A modem changes outgoing digital signals from a computer to analog signals that travel over telephone lines. Then changes the incoming analog signal to a digital signal your computer can understand.
Q: What is the difference between a hardware modem and a software modem? A: A software modem (aka Winmodem) is a modem that can connects to your PCI slot and uses Windows to do all it's main functions. It uses your computer to process the data that the modem receives, which can slow down your downloading times and raise latency. A hardware modem can either
connect to a PCI slot or connected to your computer via serial/USB. Hardware
modems have their own on-board controllers, so your computer doesn't do
as much work. Hardware modems normally provide better compression of downloads
and lower ping times.
Q: What is a LAN modem? A: A LAN modem is a modem that runs on a local area network and is basically a 56k modem with a router and switch built in. These can provide multiple computers with the same connection, but for each computer surfing, the speeds will slow vastly. These modems are generally more secure because they provide each computer with a private IP address.
Q: The V.92 Protocol A: V.92 is a new standard for dial-up communications that offers several important improvements over the existing V.90 standard. These improvements are intended to make communications faster, easier and more enjoyable. V.92 and its companion compression standard V.44, have been officially adopted by the ITU, the International Telecommunications Union.
Q: What is V.44? A: A new link-layer compression standard based on technology developed by Hughes Network Systems, V.44 will replace the current V.42bis compression technology. V.44 offers a higher compression ratio than V.42bis. How does it help? Higher compression ratios mean that more data can be downloaded in the same amount of time. The most significant improvement will be noticed when you are browsing and searching the web, since HTML text files are highly compressible. For most users, data throughput will be increased by 20 to 60%.
Q:
Why is my connection
so slow? The telephone lines have
a large effect on your dial-up connection -- length, load coils, resistive
crosses and taps and other things that do not affect voice quality enough
to require repair will adversely affect data speeds. When an analog modem
connects that horrid screech/squawk noise is the two modems talking to
each other testing the quality of the connection and what maximum speed
they can handle over that connection.
Q: Troubleshooting Your Line A: Many individuals, when presented with a problem on their dialup, pick up the phone and immediately call their ISP. Usually, very few communications problems reported to an ISP have anything to do with their modems or software. Yes, periodically a modem will not answer due to a problem, but most modem problems are on the calling end. A common misconception
among computer users is that the telephone company and long-distance switching
network is a "perfect system." The advent of error-correcting,
high-speed modems which mask line-noise and push the data transfer tolerance
window to the limit, has given us a false sense of belief that everything
should work at top speed every time.
Not so! There is that age
old problem known as LINE NOISE. Line noise may or may not be apparent
to your "naked ear", however your modem can and will react to
this annoying phenomenon. Some caller complaints which can be attributed
to line noise are:
"The system was very
slow in responding tonight."
"What I typed didn't show up on the screen until two words later." "I'm was only getting #### CPS, what's the matter with your system? "When I downloaded 156K of the 175K file you dropped carrier on me." These problems in data
signal transmission and recognition can take many forms. The callers quoted
above complained of slow system response, buffered typing response and
slow transfers. They were certain it was a problem on the ISPs system.
What was the reason? Best guess is a lousy connection most likely with
excessive line noise.
If you have line noise or any other problem with a modem connecting to your ISP, you should have your equipment or telephone line checked. What can you do when you experience modem-related difficulty? 1. Remove all other connections
to your telephone line (answering machine, fax, extension phones).
2. Use a short, shielded serial cable. 3. Increase your modem's "time-to-drop-carrier" by adding S10=20 to your setup or initialization string. 4. Have your line checked by the phone company. Additional information:
To have your line checked by the telephone company, call the local business office. Provide your name and telephone number. Tell the telephone company representative you have noise on your telephone line. Some telephone company representatives may not be helpful, claiming that they have no obligation to provide line quality sufficient for modem communications. Here is some information which might prove to be very helpful. MINIMUM LINE TESTING REQUIREMENTS AS SET BY THE FCC, your
local telephone company is required by the FCC to provide a minimum level
of quality on the lines it maintains for your use. Many lines do not meet
these standards, and so are a source of considerable noise in the transfer
of data between computers.
The telephone company may tell you there is usually only one option offered: line conditioning (at $170/line!!). This is an extra cost item that they would like to sell you. However, if their line to your computer meets the minimum standards, there is no reason you cannot have error free transfers if an error correcting protocol is used. If the telephone company seems reluctant to test your line and assures you that it meets the minimum requirements, request that they perform POTS Data Testing and provide you with the results. Let them understand that if they do not comply, you will refer the matter to the FCC. They will NOT be happy! The POTS Data Testing involves the following tests: 1) Frequency sweep 300
to 3000 Hz
2) Roll off 500 to 2500
Hz with -2 to +8 range
Request 300 to 3000 Hz with -3 to +12 range 1000 Hz tone loss -16, 1% in either direction 3) Signal to noise ratio
24 Db level
4) White noise C message
Dbrnco
5) Envelope delay measurement
6) Phase jitter not to
exceed 10%
7) Impulse noise test minimum 15 minute count Don't worry if you do not understand what all these tests mean, the telephone company knows. These standards are all available from the FCC upon request. When the lines provided to you meet these minimums, you will experience reliable, accurate, and noise free data transfers. The Hardware Setup:
Your modem is a modulator-demodulator device. It converts digital
signals (bits) sent by your computer's serial port to analog signals which
can be transmitted over telephone networks. Purchase the highest quality
modem you can afford. If you have an internal modem, you don't have to
worry about why motherboard and serial card manufacturers are still designing
equipment that won't support high-speed modems. If you have an external
modem, then your computer serial port if like most, came to you with a
slow UART chip which would work fine with 300, 1200, 2400 and 9600 baud
modems. Almost every computer shipped (even today when everyone knows
better) has this old slow chip. If you have a fast (V.32/V.32bis/HST/V.34/V.42/V.90)
modem, and are experiencing dropped characters, CRC errors and aborted
downloads, upgrade your serial port to a buffered UART (16550AFN). Look
for 82x50B, 16x450 part numbers on the large 40-pin chips on the serial
card to find out if your UART is the out-of-date device.
The Software Setup: Most of you use the Dial-Up Networking provided as part of Windows or the MAC operating system. These normally install correctly and thus work fine. Some of you use older versions of the operating systems and thus require additional software to make connections to us. Generally, all communications with the ISP have these common factors for connection: Dialing parameters:
8 DataBits, N (no) Parity, 1 - Stop Bits
Maximum Speed: set for highest recommended by manufacturer (generally 57600 for 14,400 modems, 115200 all faster modems). Special note here: Make sure your com port is set up to match this otherwise this is a bottleneck. Scripting: Generally scripting is not required for PPP connections. Flow Control: Software (XON/XOFF) for older modems (14.4 Kbps and lower), Hardware (CTS/RTS) for high-speed modems (above 14.4 Kbps), CALL WAITING: If you have the call-waiting service on your telephone line, you MUST disable it before each modem call or you risk having your connection interrupted. Call waiting is disabled with Ameritech if you dial "*70" before the telephone number. For GTE it is disabled if you dial '70# before the telephone number. The place for this is in the "dialing prefix" in your telecommunications software. If that is not available in your software, you can add this information in your dialing directory. WEATHER: Believe
it or not, rainy days and ice storms can affect telecommunications.
Q: Port Already Open / Modem Won't Hang Up A: If you get a 'Port Already Open' error when trying to establish a dial-up connection, that's Window's way of telling you some other device is using the modem. If some other device is
actually using the modem (such as a voice/fax program or you are already
on a dial-up connection), the solution is to terminate the other task
or to disable auto-answer features in its software.
Sometimes, Windows gets
confused, and it may seem like a reboot is the only answer. With Windows
95/98 in most cases, you can re-gain access to the port by terminating
the rnaapp Task:
Press CTRL, ALT & DELETE - this will bring up the Windows Task Bar Close Program box. Look for the Rnaapp task,
select it, and then click End Task.
Q: DUN Error Codes A: Error codes when connecting to dun can be found here: Modem Site Most of the error codes have a detailed explanation of what they mean and ways to troubleshoot them.
Q: Why do I sometimes have trouble connecting? A: If you have been able to connect before and suddenly find that you can't, the first thing that you should try is resetting your modem. If your modem is external, you can simply turn it off and on again. If you modem is internal, you have to shut your computer down then boot it. This should be the first thing you try if your computer cannot connect, as most often the problem will lie in your modem simply not resetting itself properly.
Q: Why do I get disconnected when I get a phone call? A: Call waiting is enabled on the phone line that you are using for your modem. The call waiting beep cuts off the signal long enough that the modem thinks that the connection has been dropped. Before following through the steps to disable it, you have to determine the call waiting code for your area, the most common code is *70 . Three other codes that are used at times are 1170 or 70# There are a few ways to check, one way is to pick up your phone, and try each code, if after dialing the code you get a dial tone again, then that code works. You can also call the operator or check the phone book for the appropriate code. How to Disable Call Waiting Windows 95/98/98SE/ME Users:
For Windows 2000 Users:
Windows 95/98/98SE/ME
problems? Try these steps:
If you use any other operating
system, then the steps necessary will vary, but you need to setup the
computer to dial the appropriate code and a comma before it dials the
number.
Q: Why am I connecting at 115.2K? A: If your dial-up networking (DUNS) CONNECT shows a speed of 57,600 (57.6k), 115,200 (115.2k), or 38,400 (38.4k), you are getting the port speed between your computer and modem, not the modem CONNECT rate. With Windows 95/98/NT,
a file with the .inf extension is used when you install your modem to
define how Windows and Windows Programs interact with the modem.
For DUNS to report the
correct speed in all cases, every possible CONNECT message must be defined
in the .inf file.
300bps (Bell 103 &
ITU-T V.21 protocol)
2400 to 12,000bps (ITU-T V.32, V.32bis and V.34 protocols) Connections limited to this range indicates severe channel impairment. Usually noise and bandwidth restrictions cause connect speeds this low. Long cable runs of over 5 or 6 miles can cause it, as can very old analog carrier systems. 14.4Kbps (ITU-T V.32bis and V.34 protocols) This is the minimum speed that a V.34 modem should be able to connect at *if* the telephone line is just able to meet specs. If this speed cannot be obtained either the modem is defective or the line is out of spec in some way. 16.8Kbps (ITU-T V.34 protocol) This is the minimum speed that most V.34 modems will actually be able to connect at on a minimally specified line. That means if the modem _can_ get this speed, the line *must* be within specs. This is also the upper
limit for connections through various types of digital carrier systems
that use ADPCM or 32K bits per channel instead of standard 64Kbps PCM
encoding. Due to lower sampling rate and fewer bits per sample more quantization
noise is generated by the analog-to-digital/digital-to-analog conversions
in these systems, thus reducing the Signal to Noise Ration (SNR) limiting
speed.
19.2Kbps to 26.4Kbps (ITU-T V.34 protocol) Speed in this range generally indicates a bandwidth limited channel. Some older carrier systems and some digital system that packetize and compress data are limited to 19.2 or 21.6Kbps connections. Long cable runs are also reasons for connect rates at 26.4K or below. 26.4Kbps, perhaps with occasional 24K and 28.8K (ITU v.34 protocol) Usually indicates a SLC that has what is called a "universal" interface to the Telco switch. Such an interface adds an extra DA/AD conversion, which prohibits a V.90/92 connection, and also adds at least 3 dB of quantization noise and a small amount of bandwidth restriction, all of which combine to usually disallow 28.8K connections. Note that for modems which can measure Signal-to-Noise Ratios, 37 dB is the *best* that can be obtained on a connection through any form of 64Kbps/channel PCM digital carrier. The specification for a voice grade telephone line is only 24 dB.
28.8Kbps to 33.6Kbps (ITU-T V.34 protocol) Indicates the line is so close to perfect that it would be difficult for the Telco to actually measure any change that would improve speed. This means SNR is better than about 32 dB, the bandwidth of the channels being used is at maximum, and the cable must not be very long. 33.6Kbps simply means the line is about as good as it can get. 28.0Kbps to 53.3Kbps (ITU-T V.92 & V.90 protocols) Means there are no sharp bends in your cable, no goblins camped in any splice boxes, and you've been blessed by a supernatural entity. These connections amount to pure FM (Freaking Magic, if you will). If you breathe funny tomorrow your speed may drop significantly! Brand new, perfect line cards may or may not work. Cables that look good might work, or might not etcetera. It all depends on parameters that have nothing to do with a voice grade telephone line. If you cannot get a V.90/92 connection the Telco is not obligated to change anything to fix it. The minimum requirements
to get a V.90/92 connection are a virtually noise free local loop (modems
which measure SNR for v.90 connections will show values from 45 dB for
lower speeds all the way up to 55-60 dB with higher speed connections),
plus a digital connection to the ISP which has exactly one Analog-to-Digital
conversion (the codec in the line card for your line at the Telco switch)
between you and the ISP.
V.90/92 modems preferentially
connect in V.90 mode if they cannot they automatically fallback to V.34.
High-end connection speed
of V.34 and low end of V.90/92 overlap. To determine if the modem is in
V.90/92 mode external modems typically include a mode indicator. For modems
without this feature connect speed can be used to determine mode. If the
modem reports 28,000, 29,333, 30,667, 32,000, 33,333, 34,667, 36,000 or
higher it is in V.90/92 mode. If the report is 33,600, 31,200, 28,800
or lower it is in V.34 mode.
Q: Checking for Phone Line Noise A: To check for line noise, pick up the phone and dial 1. You should hear nothing. If you hear a noise, go to the phone box outside of your house. Connect a phone to that box and do the same test to check for noise. If there is noise, it is a problem with the phone company. If there is no noise, turn all appliances off inside. Then do the test to check for line noise. If there is no noise, turn one appliance on, check for noise, then turn on another if there is no noise. When there is noise after turning on a certain appliance, try to put that appliance away from phone lines.
Q:
Multiple PPP One alternative is satellite.
Satellite has decent prices and will provide you with good download speeds.
The only problem is that the pings are higher than normal 56k which causes
problems for gamers. ISDN is another alternative, although it's usually
expensive.
Q: Port and Line speed: What are they? A: Port speed is the speed between your computer's serial port and your modem. The port speed can usually be set to 110, 300, 1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200 and recently 230400(up to 921600). Line speed is the speed
between your modem and the modem at the other end of the telephone line.
Depending on the modem, the line speed can be 24000, 28800, 31200, 41333,
42666, 45333, 48000, and 50666 bps. The maximum speed is 56,000(for anywhere
except the U.S.).
These settings refer only
to dial-up.
Q: Why can't data transmission over conventional phone lines be any faster? A: The Public Switched Telephone Network was originally designed for voice communications only. To reduce the bandwidth required for a voice call, engineers limited the frequencies from 0 to 4000Hz allowing more simultaneous calls (The range of the normal human voice is 300 to 3500Hz.) Unfortunately, this bandwidth range has a detrimental effect on data communications.
A: Yes. You probably won't be a target most the time, but it is highly recommended that you get a firewall. If you would like more information or need suggestions, head over to the BBR Security Forum Q:
Do I need an Anti-Virus
program? Even such a simple virus
is dangerous because it will quickly use all available memory and bring
the system to a halt.
Q: Proxies can help! A: Using high speed proxies on your browser can greatly speed up webpages and/or downloading. They also can help security on the internet.
Q:
How do I reduce
dial up time? To change your modem's
initialization string in Windows 9x/ME, open Control Panel -> Modems
-> Your modem name -> Properties -> Connection tab -> Advanced
-> Extra settings box.
Q: What is MTU? What should mine be? A: Packet size, often referred to as MTU (Maximum Transmission Unit) is the greatest amount of data that can be transferred in one physical frame on the network. For Ethernet, the MTU is 1500 bytes, for PPPoE 1492, dial-up connections often use 576. Although many say an MTU
of 1500 helps, I suggest using 576. If you're still wanting to make your
MTU 1500, read the following steps.
1) Download Dr.TCP and
change your MTU to 1500.
2) Click save then reboot your computer. 3) Dial-up like normal, then press Start>Run and type command. 4) In the command box, type ping -f -l 1472 www.yourispswebsite.com -l is a lowercase L, not a bar | Simply change it back to
576 if it gives an error of "Packet needs to be fragmented but DF
set." That error is telling you that your ISP doesn't support that
MTU.
Q: Does the RWIN affect pings or packet loss? A: No, the RWIN does not affect your pings. Ping is latency on the Net, and not your computer, therefore it can not be lowered. Latency changes every second on the Net, with the pulse of it's many users. If your line is already
lossy, a higher RWIN from Windows default (ME/2K/XP: 17520, 9x: 8760),
then it may cause packet loss.
Q: Kilobits vs. kilobytes explained A: In data communications, a kilobit is a thousand bits (1,000) bits. It's commonly used for measuring the amount of data that is transferred in a second between two points. Kilobits per second is usually shortened to Kbps (or kbps). For example, 53.333kbps is 53,333 bits per second. 1 Byte = 8 bits The lowercase b usually
stands for bits while the uppercase B stands for bytes.
To find your theoretical
download speed for your line, divide your advertised speed by 8.192:
53.333kbps / 8.192 = 6.51 KB/s or by 10 to include overhead:
53.333kbps / 10 = 5.33 KB/s
Q: STAC/MS Compression A: STAC compression can help lower your pings. How it works: Stac/Microsoft compression
compresses at the TCP/IP packet level, the data is compressed over the
complete connection. With hardware compression disabled on the modem this
means that data is also sent and received by the modem immediately, without
buffering, which reduces latency.
Select your OS below and
follow the steps on learning how to turn STAC Compression on!
Windows 9x Windows ME Windows 2000/XP
Windows 2000 and XP:
Initialization commands
are entered in "Extra initialization commands"
Q: What is RWIN? How high/low should mine be? A: RWIN (TCP Receive Window) is the amount of data that your computer can accept without acknowledging the sender. If sender has not received acknowledgement for the first packet it sent, it will stop and wait and if this wait exceeds a certain limit, it may even retransmit. This is how TCP achieves reliable data transfer. How to find your RWIN:
1) Open up a DOS Prompt
box: (Start>Run>command)
2) Type: ping -l #### dslreports.com
#### is your MSS. (MSS = MTU - 40) Take your average large
packet ping + 50%, multiply that by your proposed advertised speed and
divide that value by 8. You now have your raw RWIN.
Example: 400ms average
latency (x 1.5) with 53Kbps available downstream bandwidth:
450 x 53kbps = 23850 divided
by 8 = 2981 RWIN. Add the 50%, and you get 4471.
3) To change the RWIN:
Download DrTCP to your
Desktop.
Change the TCP Receive Window field to whatever value you got. Save, Exit, then reboot your PC.
Q: What's a good way to test actual modem performance? A: If done correctly, file downloads are a good way to test modem performance. The trick is to make sure you're really testing the modem's raw transfer rate, and not some other factor that you're not aware of. Here are some guidelines for download testing: 1. Use an FTP program
Web browsers often lie about download rates. FTP is more reliable. Note that some FTP programs reports download speeds in Kilobits per second (Kbps), while others use Kilobytes per second (KBps). To convert, multiply Kilobytes per second by 10 (eight bits plus the start bit and stop bit). (V.42 error correction strips out the start bit and stop bit, but adds other overhead, so multiplying by nine may be more accurate.) A valid alternative to FTP is a terminal program that supports Zmodem. 2. Download a pre-compressed
file
If the file you download isn't compressed, hardware data compression in the modem will kick in, leading to erroneous results. Different file types compress to different degrees, so if you download a Microsoft Word file and I download a QuickTime movie, there's no way to compare the results. Use .zip (PKZip/WinZip) or .sit (StuffIt) files for your tests. Some file formats (GIF, JPEG, QuickTime, etc.) offer some compression, but can sometimes be compressed further by hardware protocols. 3. Download a file that
is atleast 200K
A file size of at least 200K will minimize the effects of TCP/IP slow start. 4. Download a file from
your ISP's FTP
A local server is one that's on your system, not on the other side of the Internet. If you download a file from across the Internet, you're testing your ISP's connectivity to the Internet just as much as you're testing your modem. Most ISPs have FTP sites
at ftp.ispname.com. If you're on AOL, for instance, go to ftp.aol.com
to download files. There will usually be a directory called pub that contains
downloadable files.
5. Download during off-hours
To eliminate congestion issues, download early in the morning or late at night.
Q: What's a modem initialization string? A: Before your modem software dials a phone number, it initializes (inits) the modem by sending it a series (string) of commands, typically Hayes commands. These commands configure the modem's options for things like error correction, data compression, flow control, and many other parameters. The modem manual should list the Hayes commands the modem recognizes, and what effect each command has. The important thing about
modem init strings is that having the right one often makes the difference
between connecting and not. Init strings are fairly specific to each modem.
The string that made your friend's modem fly may not work at all for your
modem.
Q:
How am I downloading
faster than 56kbps speeds? For example, if your were
to download a text file, then you could see up to 14KB/s which is nearly
ISDN (128kbps) speeds, and since text files are uncompressed it can be
compressed by the modem and downloaded faster.
An MP3 file would be different.
Since MP3 files are already compressed, they cannot be compressed any
further. Therefore, the true speed is shown.
Q: Why does my IP Address change every time I dial in? A: Your IP address is a dynamic IP address that is given to you each time you dial up. When you disconnect, that IP address is freed. The odds of getting the same IP address two times in a row are very slim for national providers, but slightly more for local providers. Dynamic IP addressing saves IP address space so that the ISP can serve the same amount of customers with less IP addresses.
Q: Do DSL filters affect modem performance? A: Yes. DSL works by sending an
"out-of-band" signal on your regular phone line. 56k Modems
operate in the normal voice range of a standard phone line ( ~150 - ~3500hz).
DSL adds a signal at much higher frequencies. (That's why not everyone
can get DSL - if your phone line is long and has load coils, they attenuate
any higher frequencies; lines served by digital carrier (SLC, DLC, etc.)
also cannot carry standard DSL signals.
The problem is: 56k modems
are pushing the limits of a standard phone line; the out-of-band DSL signal,
or the filters added on your line, can add sufficient voice-band noise
to cause significantly reduced modem performance. It may affect 56k, V.34,
as well as fax connections and speed.
If you need further support please consult
the other support pages below Configure
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