What is the difference between "upstream" and "downstream" data transfer rates?

What is the difference between "upstream" and "downstream" data transfer rates?

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Downstream refers to the information that you receive from the internet. When you download a file, that is considered downstream because you are downloading information from the internet to your computer. Upstream is the reverse of downstream. Upstream is information that you send from your computer over the internet. When you send an email to somebody, or you send an attachment to somebody, that is using your upstream to send it, and it's using downstream when you receive an email or an attachment.