ISDN common fault and exclude
Light (2001-02-15 21:07) 〖Back〗〗 Forward〗
1. Some users reflect the rate after ISDN dialing is only 10 days K, if it is byte, then you are already using 128K dial-up. We should except 86K, 64K 128K refers to BITS / S, converted into a browser or FTP software display bytes / S, should be except 8. This is the case regardless of ISDN or MODEM. 2, is ISDN how much than ordinary dialing? If you visit the domestic site (out of Liaoning Province), ISDN will be more fast than Modem, but in order not to ensure the rate of 64k / 128K, specific should be regarded as the degree of network congestion at the time. Some ISDN users can download software in the province of 128k to more than 10K, and once the download of the province is a large decline in this reason. Seeing foreign sites, ISDN is limited by MODEM, mainly because of export bandwidth, this year China Telecom will continue to expand the export bandwidth, and the speed of ISDN will also greatly improve, and Modem has reached the limit, it is difficult to improve . Some users reflect 263 on both MODEM and ISDN, access the same site, why is ISDN slower than Modem? (Reaction) The computer icon light flashing frequency is different) So, the reason for explaining the above phenomenon is: modem is an analog connection, and the connection rate of connection at the next foot of the browser always has a byte transfer, which seems to transmit data. It feels faster; and ISDN is a digital connection. When there is data transmission, the connection rate of the next foot below is displayed, there is not much time when there is no data transfer, it seems very slow. In fact, ISDN is not much more fast than the MODEM transmission data, it will not be slower than modem, this can download the same file at the same site, see the actual usage time, make a comparison. 4, how to determine whether the telephone line is connected from NT1? So use Shanghai Shei Electric as an example. First, look at the power light, when power is powered by the telephony station, the local AC adapter is green. STATUS light indication Working status. Flash (8 times / sec) Indicates that the U port is connected, slow flash (1 time / second) indicates that the S / T interface is in connection. If you are bright, it means the connection is successful .5, call I often have noise in general. If ISDN is changed, the phone sound quality will be better than the original. If there is noise, please check the wiring section, see if there is a wiring is not good, if normal, call 112 lines, look at the outside any questions. 6. What is the maximum distance from NT1 to the terminal? Shanghai Bell's products can support 1000 meters. 7. Can ISDN not reach 64k / 128K? Why do I feel ISDN without MODEM? One B channel of ISDN is definitely 64K, two B is 128K, this is not worried, because he is a digital transmission form, so it will not be influenced by the simulation and the transmission rate is unstable. Not an ISDN itself, but is ISP allocates how much bandwidth is allocated for ISDN, and the bandwidth of the ISD is 64K, and the bandwidth allocated for the Modem is 2m, then ten users use ISDN Internet, Of course, there is no ten users to use MODEM. 8. Can Linux access to ISDN? : LINUX is of course, the problem is that you need to find the corresponding driver. As far as I know, there is someone who has written some ISDN cards under Linux, but it should be good for North America. ECION may have a play. You go to the Internet to find the drive, there is driven, then see if there is any corresponding hardware in China. buy.
