56K Modems
56k Modem Questions
How fast your modem should be.
FCC(in the U.S) and CRTC(in Canada) regulations prevent all devices attached to the telephone network from exceeding a certain power output. As a result, the output had to be scaled back, which has a direct effect on the speed at which data can be transfered. Currently, the server modem limit is set to 53333. This does not mean that you will not be able to hit the higher speeds, it just decreases the likelihood.
Why is your X2 slow.
There are many factors which can influence the connection rate and the speed at which you transfer data. Even though one end of the connection is pure digital, there are things that can hamper an x2 connection, while not necessarily preventing it altogether. Essentially, the qualities of the phone line plays an essential role in the speed of the connection. (i.e. line noise possibilities and line quality)
The Kflex56 modem.
The kflex 56.6k modem is one of the new 56k modems that have been released. Unlike the X2 the the Kflex requires us to have a separate line and a Kflex modem for you to connect to. If you had another modem and have upgraded to the kflex you will have to change the dial in phone number to 567-6574. This is the new number for our Kflex modem pool. If you continue to dial the old number you will not go at 56k speeds but you will still be able to connect. You will just go at 33k speeds (or possibly slower).
Another important fact to know is that the Kflex modem will only transfer at 56k while downloading throught the internet. It will not move at 56k speeds if you are uploading or if you are not connected to the internet and transfering with someone from your kflex to their kflex. The kflex technology was designed solely for receiving information from the internet and will not go at 56k speeds otherwise.
There is a known problem with some Kflex modems. When you dial in, if you are immediatley disconnected try putting four commas (,,,,) after the phone number.
In addition to the above, the new standard, V.90 has been agreed upon and it is highly recommended that you contact your modem manufacturer and upgrade to this new standard (Most manufacturers are offering this upgrade for free).
Connection Speed Issues
Help! My 56K modem connects at 33.6 or less!
Treat this as a troubleshooting matrix. Go through all of these steps, and you will have a better than 90% chance of solving your problems with slow connects.
THE OBVIOUS STUFF
We hate to ask, but you did check the obvious things, right?
56K requires that both ends have 56K modems, and they both have to use the same kind of 56K technology (x2, K56flex, or V.90). Despite what you may have heard, V.90 is not the same as x2 or K56flex. It is a third and distinct 56K protocol. Storm Internet supports all 3 of these protocols, however, it is strongly recommended that you upgrade to the V.90 protocol, which should be a free upgrade from your manufacturer
THE EASY ANSWERS
Things that are easy to try even if you don't know much about computers. Don't skip this section, because these fixes often work.
- If there is a telephone, answering machine, etc., plugged into the back of the modem, unplug it from the back of the modem. The modem is supposed to ignore devices plugged into it when it is online, but that is not always the case.
- Try disconnecting additional telephony devices (fax, phones, answering machines, alarm systems, etc.) from the phone line, even if they're in a different room. We've heard from subscribers with connect speeds jumping 10K when they unplugged a fax machine or cordless phone in another room.
- Also try running the phone line directly from the back of the modem to the wall, without passing through surge suppressors, splitters, phone line extenders, etc. This is a basic and useful step in modem troubleshooting.
MODERATELY DIFFICULT ANSWERS
It's always a good idea to check the manufacturer's web site to see if there is a more recent firmware version available. Many people's problems have disappeared once they installed a new version of the firmware. Even a modem purchased last week could be packaged with software and code that is over a year old
If your modem supports more than one 56K protocol, you may want to tell it which protocol (V.90, x2, or K56flex) it should use. The commands are listed below.
V.90/K-Flex
|
Desired
Connection Type
|
Add
this to your modem init string
|
| V.90 preferred (K56flex
will still work) |
+MS=12,1 |
| V.90 only, K56flex
and V.34 disabled |
+MS=12,1,34667,56000 |
| K56flex preferred
(V.90 will still work) |
+MS=56,1 |
| K56flex only, V.90
and V.34 disabled |
+MS=56,1,34000,56000 |
| Disable V.90 and
K56flex, use V.34 (28.8/33.6) |
+MS=11,1 |
X2/V.90
| Desired Connection
Type |
Add this for Sportster(non
USR) |
Add this for Courier |
| X2 Only |
S32=66 |
S58=32 |
| V.90 Only |
S32=34 |
S58=1 |
| X2 and V.90 |
S32=2 |
S58=0 |
| Neither X2 nor V.90 |
S32=98 |
S58=33 |
OR MAYBE IT'S YOUR PHONE LINE
We were hoping it wouldn't come to this, but it may not be your modem or inside phone lines at all.
It may be that the phone lines in your immediate neighborhood don't support 56K.
The fact that your modem can connect at 56K speeds to a long distance number is no guarantee that the same is true of local numbers, and vice versa. Long distance calls may be routed through telephone circuits which are significantly better or significantly worse than the local circuits used to connect to Storm.
How to find out for sure if your phone lines support 56K:
This is the only reliable way we know of to test your phone lines: borrow a known good 56K modem and try it with your phone lines. By "known good 56K modem," I mean a modem that has connected at speeds higher than 33.6. Remember that connects speeds of 38400, 57600, and 115200 aren't true connect speeds, so they don't count.
If it's an internal modem, have your friend bring the whole computer to your house. In fact, it's easier that way, because his computer will already be configured for his modem. Let him use your monitor, keyboard, and mouse so he won't have to cart them over to your house.
If you can only borrow the modem, be sure to get the disks that came with the modem so you can install the drivers for that modem. You'll have to install the modem and drivers. Be sure to select the modem in your dialing software (such as Windows 95 Dial-Up Networking or Apple's PPP for Open Transport).
Once his modem is at your house, call his ISP. How fast is the connection? You can also try calling Storm, if Storm and your friend's modem use the same 56K protocol (x2, K56flex, or V.90).
Office PBX systems generally create an extra A/D conversion. How do you know if you're on a PBX? If you have to dial a number (usually 9 in the U.S.and Canada) to dial an outside line, you're on a PBX. If your phone has its own extension, you're on a PBX. The solution in that case is to plug the modem into a direct outside line. The office fax machine is usually dialed into a direct outside line, so try that.
The phone lines outside of your building may have equipment that introduces extra A/D conversions. Non-integrated SLCs (subscriber line concentrators) are one source. If that's the case, there's little you can do except to call the phone company and complain. Before you get your hopes up, be aware that the phone company is generally not sympathetic, and only guarantees speeds of 9600 baud or so. It is worth a shot, though, and some people have managed to get their phone company to re-route the lines.
Even if I don't connect at 56K, I'm guaranteed 33.6, right?
No. In fact, even if you and Storm were using 33.6 modems, you still wouldn't be guaranteed 33.6 connects. Few people get 33.6 connects. A large number get 28800 or 31200 connects, but many people only connect at 26400, 24000, or even slower. The phone lines in some areas simply can't support higher speeds.
If you'd like to try improving the speed, make sure you have the latest firmware and drivers/settings files. Also, try passing the phone line directly from the back of the modem to the phone outlet on the wall. Passing the phone line through surge protectors, phones, answering machines, etc., has sometimes been responsible for slow connects.
Again, though, your phone lines may simply not support higher speeds.
I'm connecting at 38400, 57600, or 115200. Or am I?
No. Those speeds are computer-to-modem speeds (AKA DTE speeds or port speeds) that you set in your software. What you want to know is the modem-to-modem speed (AKA connect speed or DCE speed).
How can I get my modem to report the true connect speed?
For Windows 95 Dial-Up Networking and Apple's PPP for Open Transport
You must install the correct drivers for your modem. For instance, you would need to the correct .inf file for Windows 95 Dial-Up Networking, or the correct CCL file for Apple's PPP for Open Transport. The drivers interpret the result code from the connection and translate it into a connect speed. Without the driver, you won't get an accurate connect speed. These may have been included on a disk with the modem. If not, check the Operating System Installation CD or the manufacturer's web site.
If you have the correct driver/settings file and you still don't get the true connect speed, add one of the init strings below to your init string.
For other programs that do not use driver files
- According to 3Com/U.S. Robotics, any init string that includes AT&F1 should report the true connect speed.
- For most Rockwell-based 28.8 and K56flex units, the command is W2. (For Rockwell-based PCI modems, the command is MR=2.) However, several commands can override W2, including the S95 commands and the &Q commands. If W2 doesn't have the desired effect, you might try adding S95=0 or S95=1 to the init string.
What are typical connect speeds for 56K modems?
As with 33.6 modems, your results will depend heavily on your phone lines. To see what kind of performance other people are getting, see the performance survey. Typically, 42-46K for K56flex and anywhere from 44-52K for x2 is good performance. Some people are getting better results, some are getting worse.
Is initial connect speed all it's cracked up to be?
Initial connect speed is a convenient benchmark, but it can be deceiving. V.34 and 56K modems can and do shift their speeds up and down during the course of the call to respond to changing line conditions. Some modems connect very aggressively at high speeds, but are then forced to lower their speed to a more stable level. Others may connect conservatively and upshift.
The best test is to download a compressed file with FTP. For help with getting accurate results, see the section below on FTP.
What's the command for connection speed and stats on my K56flex?
Lucent-based K56flex modems
- After disconnecting, issue an AT11 command in your terminal program.
Rockwell-based K56flex modems
- After disconnecting, issue an AT&V1 command in your terminal program. These are some example results. TX is the transmit (upload) speed. RX is the receive (download) speed.
AT&V1
TERMINATION REASON.......... LOCAL REQUEST
LAST TX data rate........... 31200 BPS
HIGHEST TX data rate........ 31200 BPS
LAST RX data rate........... 46000 BPS
HIGHEST RX data rate........ 50000 BPS
Error correction PROTOCOL... LAPM
Data COMPRESSION............ V42Bis
Line QUALITY................ 127
Receive LEVEL............... 014
Highest SPX Receive State... 00
Highest SPX Transmit State.. 00
EQM Sum Value............... 00A2
RBS Pattern detected........ 00
Data Rate Dropped in kbps... 00
Digital Pad Detected........ None
What's the command for connection speed and stats on my USR?
After disconnecting, issue an ATI6 and ATI11 in your terminal program. These are some example results. Note that the ATI6 Speed line shows the highest download/upload connect speeds. The ATI11 command shows the number of upshifts and downshifts for receive (RX) and send (TX).
ATI6:
Chars
sent
580 Chars Received
49642
Chars lost
0
Octets sent
360 Octets Received
26533
Blocks sent
191 Blocks Received
805
Blocks resent
0
Retrains Requested
0 Retrains Granted
0
Line Reversals
0 Blers
1
Link Timeouts
0 Link Naks
0
Data Compression
V42BIS 2048/32
Equalization
Long
Fallback
Enabled
Protocol
LAPM SREJ 128/15
Speed
46666/31200
Last Call
00:04:34
Disconnect Reason is Escape code
ATI11:
USRobotics Courier V.Everything Link Diagnostics...
Modulation
x2/V.34+
Carrier Freq ( Hz )
NONE/1920
Symbol Rate
8000/3200
Trellis Code
NONE/64S-4D
Nonlinear Encoding
NONE/ON
Precoding
NONE/OFF
Shaping
OFF/ON
Preemphasis Index
NONE/0
Recv/Xmit Level (-dBm) 15.7/12.2
SNR
( dB ) 61.5
Near Echo Loss ( dB ) 10.2
Far Echo Loss ( dB )
Roundtrip Delay (msec) 26
Timing Offset ( ppm) -1406
Carrier Offset ( ppm) 68
RX Upshifts
0
RX Downshifts
1
TX Speedshifts
0
x2 Status
0000; 0000-0000-0001-0000-0000-0000; 00,00 0031;03
What's a good way to test actual modem performance? (FTP downloads)
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.)
2. DOWNLOAD A PRE-COMPRESSED .ZIP OR .SIT 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'S AT LEAST 200K
A file size of at least 200K will minimize the effects of TCP/IP slow start.
4. DOWNLOAD FROM THE STORM FTP SERVER
The Storm FTP Server is local, not on the other side of the Internet. If you download a file from across the Internet, you're testing Storm's connectivity to the Internet just as much as you're testing your modem.
5. DOWNLOAD DURING OFF HOURS
To eliminate congestion issues, download early in the morning or late at night.
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