It should be noted that due to some brands of ADSL Modem DC transformer quality is not satisfactory, in the summer after a long period of use will be overheated due to the output voltage generated by the disorder caused by the ADSL Modem internal error. At this time, we can only take the ADSL Modem to power off and restart the method. If you can't, you can only ask the DC transformer to cool down first. Lastly, I would like to say that if you are using your computer in a normal way and suddenly can't access the Internet, you may want to give your ISP a call to see if the line is normal.
In most cases, computer users are more concerned about stability than they are about speed. The lack of Modem stability and the resulting dropouts are undoubtedly one of the most important and sensitive topics for Internet users. It is inevitable that the internet connection will drop occasionally. However, if the Modem drops frequently, it means there is a problem. From the various reasons for the dropout, we propose some countermeasures to avoid the dropout, and hope to be able to help all users.
Dropouts with invalid DTR signal
Reason for dropouts: Under the default setting, if the DIR (Data Terminal Ready) signal is invalid (including the temporary invalidation of the signal), the Modem will usually experience dropout failures.
Optimization Countermeasures: At this time, such problems can be solved by using the additional instruction S25=200. This instruction actually sets the time interval value (in hundredths of a second) for the DTR signal to be invalid, that is to say, if the DTR signal is invalid for a period longer than the set value, it will cause a dropout. As long as this time interval value is set longer, you can avoid the dropout caused by the temporary invalidation of the DTR signal due to unexpected interference.
Note: Some Modems do not improve much with this setting. The original setting values of various Modems can be queried with the ATS25? command within Hyper Terminal, and the original setting values are generally smaller (e.g., the setting value is 5).
Temporary Loss of Carrier Drops
Reason for Drops: If the Modem cannot correctly distinguish whether it is a true drop of the remote Modem or a temporary loss of carrier due to unexpected line interference, it will often cause a drop as well.
Optimization countermeasures: At this time, you can add an additional instruction S10=100 to solve this kind of problem. This instruction actually specifies the delay time (in tenths of a second) between the remote carrier loss and the local hang-up, that is to say, if the carrier loss lasts longer than the set time value, the Modem will think that it is the remote Modem interrupts the connection, and thus also drops the line. Setting the time interval to a longer value will prevent temporary carrier loss from causing a drop.
Note: Some Modems do not improve much with this setting. By using the ATS10? command within HyperTerminal, you can query the original setting value (e.g., the initial setting value is 14) for various Modems.
Dropouts due to inherent defects in the phone line
Reason for dropouts: In order to make data transmission stable and reliable, Modems usually automatically reduce the connection rate with the remote Modem appropriately according to the actual line conditions, so dropouts will occur if there are inherent defects in the phone line.
Optimization countermeasures: When the Modem connection speed is not high or often dropped, it may be worthwhile to carefully examine the inherent defects in the telephone line. For example, if the phone line in the phone line is used for too long, should be replaced with a new line. Also check the phone line of the various connections such as plugs are in good contact, in addition to the indoor telephone leads are often not shielded and easy to introduce interference, and indoor telephone line distance increase and incorrect wiring will also affect the quality of the line, so the first thing to do is to ensure that the phone line away from the power lines and other sources of electromagnetic radiation, and then you can remove the phone line of any other equipment (including extensions, splitters, etc.), to remove the extension or the splitter, etc., it is often possible to remove the extension or the splitter, etc., after a long time, the telephone line should be replaced with a new one. splitters, etc. will often significantly increase the Modem's connection rate after removing the extension or splitter.
Note: In general, it would be nice if you could have your phone line serviced or replaced once a year.
One, eliminate the inherent defects of the telephone line
In order to ensure that data transmission is stable and reliable, Modem will usually be based on the actual line conditions automatically appropriate to reduce the rate of connection with the remote server Modem, so if the telephone line there are inherent defects in the problem will be dropped. At this point, you can check the Modem's connection speed, if the speed is not high but often dropped when, may wish to telephone lines in the existence of inherent defects in the careful examination.
First of all, check whether the connecting plugs of the telephone line are in good contact, and if the telephone line has been used for a long time, you should replace it with a new one. In addition, because the indoor telephone leads are often unshielded and easy to be interfered with, and indoor telephone line distance increases and incorrect wiring will also affect the quality of the line, so first of all, we must ensure that the telephone line away from the power lines and other sources of electromagnetic radiation, and then remove the telephone line of any other equipment (including extensions, splitters, etc.), to remove the extensions or splitters, etc., go online and try to Modem's connection rate and stability! is not improved.
Two, to solve the Modem's own problems
There are many types of Modems on the market, with different models and different qualities, and the quality of the Modem itself, as well as the low compatibility between different Modems, can also lead to dropouts. To avoid this, when purchasing a Modem, focus on good quality and upgradability, and regularly update it with the latest drivers from the Modem manufacturer.
Three, cancel the call-waiting function
If your phone applies for the call-waiting function, and a call comes in while you're online, the Modem will consider the signal to be an interrupt signal from the remote Modem, and thus drop the line on its own initiative. In light of this, the only way to do this is to ask the phone company to temporarily remove the feature. Since many ISPs have an idle control function, that is, when the idle time of the Modem exceeds a predetermined value (e.g., a predetermined value of 15 minutes), the server will "kick out" the user and cause the line to be dropped, you can inquire with the ISP about the specifics of this type of problem and take appropriate measures to deal with the problem, such as improving the efficiency of Modem use and reducing the number of calls coming in. Modem use efficiency, reduce the idle time of the communication line and so on.
Four, to prevent the Internet speed is too high
Everyone knows that "things will go against the grain" of this folk proverb, if your 56K Modem 56K speed is very easy to drop the line, it may be worthwhile to set the speed of 33.6K, with the reduction of the speed to improve the rate of connection and
stability is a compromise, particularly in the case of the 56K Modem. A compromise, especially in the case of poor line conditions that lead to drop failures is very effective, try it.
Fifth, a reasonable set of route idle time
If you dial up the Internet, a long time without transmitting any other data, this time the system in order to save users the cost of Internet access, usually in the line idle more than the set value of a certain period of time, generally 30 minutes, the system will be intelligent disconnection caused by dropping the line. Therefore, you can set the appropriate line idle value according to your actual situation and needs.
Sixth, to prevent temporary loss of carrier
In the process of network operation, if the Modem can not correctly distinguish between the remote Modem in the end of the real drop, or due to accidental line interference caused by the temporary loss of carrier, often also caused by dropping the line. At this point, you can solve this type of problem by adding the additional instruction S10=100. This instruction actually specifies the delay time (in tenths of a second) from the remote carrier loss to the local hangup, and by setting this time interval value to be longer, you can avoid the drop caused by the temporary carrier loss. However, there are some Modems that won't buy it, and even with this setting it won't make much of an improvement. You can query the original settings of various Modems by using the ATS10 command in HyperTerminal, and modify them appropriately.
VII. Preventing the DTR (Data Terminal Ready) Signal from Being Invalid
By default, if the DTR (Data Terminal Ready) signal is invalid, including the temporary invalidation of the signal. Modem will usually then fail to drop out. At this point, such problems can be solved by employing the additional instruction S25=200. This instruction actually sets the time interval value (in hundredths of a second) at which the invalidation of the DTR signal causes a dropout, i.e., if the invalidation of the DTR signal lasts longer than the set value, a dropout will occur. As long as the time interval value is set longer, you can avoid the dropout caused by the temporary invalidation of the DTR signal due to unexpected interference.
VIII. Optimizing the system
As we all know, the default settings of a computer system are not the best settings, so dropouts are inevitable. So almost all the Modem manufacturers for Modem often drop the problem, through some tools on the Modem optimization process, so that the Modem will be based on the actual line conditions and automatically reduce the appropriate rate of connection with the remote Modem. Of course, you can also purchase or download related optimization software to optimize your system for efficient and stable operation.