曾经被允诺为可以用铜质电话线传输的廉价拔号ISDN,也许应是如下英文词句的缩写:It Still Does Nothing。的确,在这一领域厂商有些令人失望。例如:大的电信公司如AT&T和MCI,除了宣布计划提供拨号ISDN Internet服务(那已是今年夏天的往事了)以外,尚无一点实质性进展。而一些本地电话公司提供的拨号ISDN访 Once promised to be a cheap dial-up ISDN that can be transmitted over a copper telephone line, perhaps it should be an acronym for the following English words: It Still Does Nothing. Indeed, vendors are a bit disappointing in this area. For example, major telecom companies such as AT & T and MCI have not made any substantive progress other than announcing plans to offer dial-up ISDN Internet services, which is already the summer of this summer. Dial-up ISDN provided by some local phone companies