You sound as though you are on an ADSL connection with an 8Mb/s contract. The ISP configures your download and upload speeds and as most people use download they fix the download speed to be high and the upload speed to be low. The total of upload speed plus download speed is normally in the region of the 8Mb/s which is approximately what you have. If you wish to increase your upload speed then talk to your ISP but increasing your upload speed will correspondingly decrease your download speed.
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