Please make sure if your ISP (Internet Service Provider) supports multilink PPP for using 128K high-speed connection. And also please ask the provider if you have to do some additional settings for multilink PPP.

What operating system do you use?
If Win 95 or Win 98, we suggest you refer to the Section 2.6 of the user's manual or the on-line manual for detailed configuration of Dial-Up Networking.
For Win 95 you can add additional device for multilink PPP by configure "Dial-Up Networking" properties.
For Win98 you can add additional device for multilink PPP by configure "Dial-Up Networking" Multilink.

For NT4.0, you can configure Dial-Up Networking as follows:
To open "My Computer" and run "Dial-Up Networking"
To click or select "More" item.
To click "Edit entry and modem properties
To click or select "Configure" item and select "Multi Lines" then you can get on Internet with 128k bps high speed.

And, if your ISP supports only TCP/IP over V.120, you have to install the optional bundled software RVS-COM lite and configure the "RVS ISDN V.120" as modem device in Dial-Up Networking. You also have to start CommCenter of RVS-COM before dialing the call. We suggest you refer to the Section 2.6 of our user's manual or the on-line manual for detailed configuration of Dial-Up Networking.