TP General - Problems connecting at 56K speeds

7.847 bytes

Service Hints & Tips

Document ID: DSHY-424LE6

TP General - Problems connecting at 56K speeds

Applicable to: Canada, United States

Symptom:
Only getting a connection of 28.8 or less with a 56K/V.90 modem.

Configuration:
Any system with a 56k modem installed.

Workaround:
Make sure that you are using the latest drivers for the modem you are trying to use.

Additional information:
Possible Causes:

1.) Possible noisy phone lines.
High speed modems are designed to "retrain" their signal or lower their connection speeds in the case of noisy conditions. This will lead to the modem lowering its speed until it is able to get a clear, consistent connection speed.

2.) Wrong protocol is being accessed.
There were originally two competing 56K protocols; x2 from USR and K56Flex from Rockwell and Lucent Technologies. The Lucent spec was soon discarded and they worked with the K56Flex spec. During this past year, a joint standard, V.90, was proposed and was officially ratified in September of 1998. In order to connect at 56k speeds you will need to make sure that you are calling the same protocol. To connect at V.90 to a V.90 modem, you will need to have V.90 software on your system. If you have either the x2 or K56Flex protocol only, you will NOT connect at 56k speeds.

If your system has:

and the Server is:

then you are capable of making a connection of:

x2

V.90 only

V.34 only

K56Flex

V.90 only

V.34 only

x2 and V.90

V.90 only

V.90 is preferred (and will be tried first), but V.34 can/will be used if V.90 is unsuccessful

K56Flex and V.90

V.90 only

V.90 is preferred (and will be tried first), but V.34 can/will be used if V.90 is unsuccessful

x2

V.90 and x2

x2 is preferred (and will be tried first), but V.34 can/will be used if x2 is unsuccessful

x2 and V.90

V.90 and x2

V.90 is preferred (and will be tried first), but x2 is also possible. V.34 can then be used if V.90 and/or x2 is unsuccessful

Make sure that the server you are calling matches your protocol. If your modem is V.90 and was originally x2, look for an access number that matches that criteria. Not all areas will have modems that match both of the older protocols. Check with your ISP for updated phone numbers.

3. ) The V.90 standard was official ratified in September of 1998. Previous releases of V.90 code were done based off of a pre-release specification. These releases may or may not have issues with the final official specification that can cause some connectivity problems. Check with your modem manufacturer and make sure the latest drivers are installed for the modem you are trying to use.

4) Phone switch problems. The phone companies Central Office switch configuration or type of switch being used may not allow high speed protocol connections. This usually occurs in areas that have older Central Office switches or older lower quality phone lines that the local phone service routes through. This may be at the customer location, the destination location where they are calling, or anywhere the call is routed through between the two. Most times, long distance calls route through the newer switches which are better configured for high speed connections and have a lower chance of resulting in the slower connections. IBM is unaware of a way to test phone lines for K56Flex modems. If, however, you are using an x2 modem, you can check the following USR web page: http://www.3com.com/56k/need4_56k/linetest.html

You should check with your local phone company and have them check your telephone lines. There may or may not be a charge associated with this.

5.) If you are able to connect to test lines and it shows you are capable of high speed connections, check with your service provider to see if they have reports of problems connecting at high speeds. It could be that it is a switch close to the provider that is the cause of the slowdown. You may also want to try other local numbers for provider or long distance number to compare as a test.

Search Keywords

Hint Category

Communications, Modems, Windows 95, Windows 98, Windows NT, DOS/Windows 3.x, OS/2

Date Created

10-11-98

Last Updated

06-04-99

Revision Date

06-04-2000

Brand

IBM ThinkPad

Product Family

ThinkPad 390, ThinkPad 390E, ThinkPad 600, ThinkPad 600E, ThinkPad 770, ThinkPad 770E/ED, ThinkPad 770X, ThinkPad 770Z, ThinkPad i Series 1400, ThinkPad i Series 172x

Machine Type

2626, 2645, 2646, 9548, 9549, 9544, 2611, 2627

Model

Various

TypeModel

Retain Tip (if applicable)

Reverse Doclinks
and Admin Purposes

If your system has:	and the Server is:	then you are capable of making a connection of:
x2	V.90 only	V.34 only
K56Flex	V.90 only	V.34 only
x2 and V.90	V.90 only	V.90 is preferred (and will be tried first), but V.34 can/will be used if V.90 is unsuccessful
K56Flex and V.90	V.90 only	V.90 is preferred (and will be tried first), but V.34 can/will be used if V.90 is unsuccessful
x2	V.90 and x2	x2 is preferred (and will be tried first), but V.34 can/will be used if x2 is unsuccessful
x2 and V.90	V.90 and x2	V.90 is preferred (and will be tried first), but x2 is also possible. V.34 can then be used if V.90 and/or x2 is unsuccessful

	Search Keywords
	Hint Category	Communications, Modems, Windows 95, Windows 98, Windows NT, DOS/Windows 3.x, OS/2
	Date Created	10-11-98
	Last Updated	06-04-99
	Revision Date	06-04-2000
	Brand	IBM ThinkPad
	Product Family	ThinkPad 390, ThinkPad 390E, ThinkPad 600, ThinkPad 600E, ThinkPad 770, ThinkPad 770E/ED, ThinkPad 770X, ThinkPad 770Z, ThinkPad i Series 1400, ThinkPad i Series 172x
	Machine Type	2626, 2645, 2646, 9548, 9549, 9544, 2611, 2627
	Model	Various
	TypeModel
	Retain Tip (if applicable)
	Reverse Doclinks and Admin Purposes