i would be much pleased if somebody could tell me how to install internal dial up modem in ubuntu 11.10
By "Install internal dial up modem" do you mean installing the hardware? In that case, as most internal dial up modems are PCI, just open your PC case and insert it to an available PCI slot.
If you mean setting up the driver and the dial up software, read on:
Using internal dial up modems are problematic in Linux. Internal modems are also called softmodem or winmodem. For most of the softmodems, there is no driver for linux. Its not a problem or shortcoming of Linux though. The modem makers generally were never very keen to make Linux drivers. I can give you an example. In 2004 I bought a branded desktop(Compaq Presario 1130il, I still remember the model name
) It had Turbolinux 10 preinstalled.(Turbolinux is history now). It had an internal dial up modem. Compaq supplied me a disk containing the driver(binary, ofcourse) for the modem built against Turbolinux v.10. Later when new and attractive distros(like Ubuntu, Mandriva etc) started to emerge, I began to dislike Turbolinux.(But do not think Turbolinux was bad, it was awesome, much better and far less buggier than Ubuntu used to be at its early days). I particularly liked Mandriva 2007 and installed it as my primary OS. But then the problem began. It had no driver for the modem and nowhere in the internet I could find a driver for my modem for Mandriva. How would I? The modem maker(Agere systems) and Compaq supplied only binary driver and that to only for Windows and Turbolinux. Had they realease the source, I could build the binary for Mandriva 2007 and subsequent versions.
For exactly this reason, I had to keep using Turbolinux,(which was dead by 2008) even in the year 2009. And then our very beloved BSNL brought Broadband and suddenly there was no need to use the softmodem.