Preparing for Networks Exam

Day after tomorrow, i am having Networks exam. Preparing for the same.
No other great news. After the exam, i will be installing NVidia driver for my GeForce MX graphics card. Last time when i installed i made a mistake of not keeping the internet connection on. This time i guess i wont make that mistake as my modem does the dialling now. This method of NATed internet usage seems safe since all those Microsoft Network Discovery packets are cleanly filtered. Not only that, most port scans are totally filtered. Above that i have my firestarter in Linux and a good firewall for windows. Today Venks downloaded a 30 MB file (i wont tell what it is! ;-) ) from my system. It took an hour since my upload speed is around 6 KB/s. my bsnl broadband seemed much faster than it usually is. Yesteday i got speeds around 35 - 40 KBs.What happened to BSNL ? Is something wrong? ;-). OK got to study. Bye