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Comment by selykg | Hacker News Reader

I'm sort of in a very rural area. Farm fields across the street from me. But I'm also ~5 minutes or so away from downtown.

I have available to me gigabit (down) from Comcast. I had it for awhile and it was glorious but it was also $80/mo on promo and $110 when not. The reason I got it was not for the download speeds, it was the faster upload speeds that came along with it. Still slow, and not even remotely close to speedy. But it was a solid 12mbit up. Compared to the 5mbit up I get on my 100down plan.

I would kill for some reliable upload speeds. It's awful anymore just sending images to people, never mind you want to send a quick minute long video to someone and it takes several minutes to send.

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Any network engineers around? What leads comcast to offer such lopsided connectivity? I mean having some sort of asymmetry is normal and somewhat justified, but usually were talking something like 1:10 upstream:downstream. Here parent comment has fairly extreme 1:83 instead!? I imagine there must be some reasoning behind it, but I just can't figure what that would be.

Someone can correct me if I'm wrong, but DOCSIS over coax isn't full duplex. It's multiplexing send and receive over the same wire. Since download bandwidth is more important they provision their network design to maximize the amount of downstream bandwidth available. They also have an extreme level of oversubscription.

My understanding is that it’s not a technical issue, but rather a business and marketing one. Comcast doesn’t want the home service to compete with their costlier Business service, so they artificially limit the upload speeds to prevent home/consumer users from serving a high volume of content using their less-expensive service.

The last mile DOCSIS bandwidth is shared among all of its user. So you want to maximise the download which is used 90% of the time. The problem is somewhat solved ( or lessen ) in DOCSIS 4.0 Full Duplex Extension. But as with everything DOCSIS the lead time to market is extremely long.

I believe, but am not a network engineer, that more channels of the system are dedicated to downstream and the standard prioritizes it.

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