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ftj napisao:bolje da su se vise otvorili za upload.

ftj napisao:Mislis njih kosta vise da ti daju upload? Deder mi objasni to, pogotovo u slucajevima optike do zgrade.

It's mostly design intent. Until recently, Internet usage was extremely asymmetric, meaning that people downloaded far more than they uploaded. With this in mind, the technology designers created equipment that favored download speeds.

The reason for the trade-off is because there is only so much frequency available in the transmission medium, whether it's coax for cable or a phone line for DSL. Higher frequencies suffer noise and signal loss sooner than lower frequencies, so there's an effective limit to how much spectral bandwidth is available. Since the available spectral bandwidth is limited, how it's used becomes an issue.

Since the design intent is for higher download speeds, more of the available frequency is assigned for download and less is assigned for uploads.

A further complication is from the way both DSL and Cable fan out. The connections all terminate next to each other at the provider end in closely packed equipment and in the cable runs to the equipment. At the subscriber end, the terminations are far apart (ie at different buildings). This causes more crosstalk at the provider's end of the connection. The signal originating from the provider is less susceptible to crosstalk than the weaker signal arriving at the provider from the subscriber. This phenomenon further impairs the subscriber's upload bandwidth.