MTNL Mumbai Internet connection fails while uploading files

[Prathamesh]

I face this strange issue, whenever I try to upload files, my internet connection (MTNL) fails. It is okay uploading upto 1-2Mb and after that the connection shows no internet access. I have to reboot my modem to get internet again.

What might be the issue. My SNR is low, but downloading and surfing is good. Connection fails atleast 5 times in a day. But, whenever I try to upload, it stops immediately.