Downloading & Uploding???

[Bhoomeendra Sisodiya]

If  i download and upload simultaneously then does any of the speed get affected  

[AlTech]

5 minutes ago, Bhoomeendra Sisodiya said:

If  i download and upload simultaneously then does any of the speed get affected  

I don't think it should since both are allocated different cables (idk networking terminology) and are treated differently.

 

Interesting. First time I've ever heard this question.

[Starelementpoke]

7 minutes ago, Bhoomeendra Sisodiya said:

If  i download and upload simultaneously then does any of the speed get affected  

I want to say no. But networking isn't more forte.

[Lurick]

No, it's full duplex so it can send and receive on the same line at the same time.

[IAmAndre]

Your upload and download speed are independent from one another : uploading data won't affect your download speed and vice versa.

[Prindagelf]

yes and no..  the bandwidth you are alloted by your IP is the issue, you pay for what we will say is like a 4 lane highway, but only get a set amount of use of that based on your IP's settings. Most IPs sell their packages with wording - UP to X amount upload and X amount download -, this is because they depend alot on their mass stored cashe to reduce the actual traffic over the network they pay to use.

So when you decide to upload your new data you are taking up *Real* used bandwidth and often it leads to your IP reducing your a lotted download bandwidth to compensate.

This is an auto response system of course and most users do not see a big difference in usage.

[Lurick]

47 minutes ago, Prindagelf said:

yes and no..  the bandwidth you are alloted by your IP is the issue, you pay for what we will say is like a 4 lane highway, but only get a set amount of use of that based on your IP's settings. Most IPs sell their packages with wording - UP to X amount upload and X amount download -, this is because they depend alot on their mass stored cashe to reduce the actual traffic over the network they pay to use.

So when you decide to upload your new data you are taking up *Real* used bandwidth and often it leads to your IP reducing your a lotted download bandwidth to compensate.

This is an auto response system of course and most users do not see a big difference in usage.

No, just no. That is not how it works at all.

 

Upload and download speeds are completely independent from one another and are channelized on the DOCSIS protocol on different frequencies entirely. Your ISP will not reduce your download speed when you start to upload or vice versa. They say up to X speed for download and upload because they cannot guarantee you that amount of bandwidth because of something called oversubscription where they will put in say 4 lines for a neighborhood of 12 homes and if all 12 homes hit the network at the same time then whatever the bandwidth on those four lines adds up to is what will then be divided among the 12 houses.

[Prindagelf]

46 minutes ago, Lurick said:

No, just no. That is not how it works at all.

 

Upload and download speeds are completely independent from one another and are channelized on the DOCSIS protocol on different frequencies entirely. Your ISP will not reduce your download speed when you start to upload or vice versa. They say up to X speed for download and upload because they cannot guarantee you that amount of bandwidth because of something called oversubscription where they will put in say 4 lines for a neighborhood of 12 homes and if all 12 homes hit the network at the same time then whatever the bandwidth on those four lines adds up to is what will then be divided among the 12 houses.

lets be clear on this, they all over subscribe at some point and upgrade lines and systems only after it is long overdue, and the practice or reducing download speed to compensate for this is common and almost standard.

I would love to live in your perfect Internet provided world, Please let me know what area this exists and i will move there for my perfect bandwidth harmony. 

[U.Ho]

4 hours ago, Lurick said:

No, it's full duplex so it can send and receive on the same line at the same time.

That's an if.

If it's full duplex, it can send and receive on the same line at the same time.

 

Half duplex can exist in the weirdest places, trust me. It's usually a matter of negotiation between interfaces and sometimes those negotiations give peculiar results.

 

In most cases, though, it's full duplex.

[Lurick]

12 minutes ago, U.Ho said:

That's an if.

If it's full duplex, it can send and receive on the same line at the same time.

 

Half duplex can exist in the weirdest places, trust me. It's usually a matter of negotiation between interfaces and sometimes those negotiations give peculiar results.

 

In most cases, though, it's full duplex.

Yah, it's usually when you get down into 10/100 Meg that you see half duplex but cable is pretty much full duplex, or as close as you can get, most of the time.

[mariushm]

In theory download and upload channels are independent, they don't affect each other.

In practice, it's not always the case.

 

By design, when you transfer (download) a file, your computer talks back to the remote computer acknowledging that the data packets have arrived without errors, or to report corrupted packets so that they could be resent. Therefore, when you do any download there's inherently some upload (but very tiny, a few bytes a second). 

 

If you do some upload and your ISP limits the upload speed or you upload as fast as the network card is capable of, there may not be enough "room" on the upload channel for those bytes to be inserted and sent to the remote server from where you download files, these bytes are considered low priority. So basically your download is slowed down by your upload.

If you limit your upload speed to about 95% of the maximum upload speed, there's always 5% left for other transfers. Some routers and switches are smart enough to detect this behavior and not block other connections, they have a sort of "quality of service" algorithm in them which keeps everyone happy.

[AlTech]

10 hours ago, Prindagelf said:

lets be clear on this, they all over subscribe at some point and upgrade lines and systems only after it is long overdue, and the practice or reducing download speed to compensate for this is common and almost standard.

I would love to live in your perfect Internet provided world, Please let me know what area this exists and i will move there for my perfect bandwidth harmony. 

Hong Kong has nice Internet.

[BuckGup]

13 hours ago, Bhoomeendra Sisodiya said:

If  i download and upload simultaneously then does any of the speed get affected  

Yeah it will. When my dad uploads photos my download goes from 10Mb/s to 6Mb/s and my ping goes from 40ms to 700ms.

[AlTech]

2 minutes ago, SamStrecker said:

Yeah it will. When my dad uploads photos my download goes from 10Mb/s to 6Mb/s and my ping goes from 40ms to 700ms.

lol. Never happens to me.

[BuckGup]

19 minutes ago, AluminiumTech said:

lol. Never happens to me.

Uploading effects ping which can congest your network causing slower downloads

[Bhoomeendra Sisodiya]

14 hours ago, AluminiumTech said:

I don't think it should since both are allocated different cables (idk networking terminology) and are treated differently.

 

Interesting. First time I've ever heard this question.

well in my location i get 60KB/s downloading speed so it i a big deal for me 

[U.Ho]

When you upload something at the maximum rate your router can push out from the WAN interface and someone else starts an upload in the same general direction, the upload speed is split in two usually pretty much equal upload speeds that sum up to the total maximum.

 

When you upload something at the maximum rate and someone else starts a download, the speed should remain as pretty much full for each operation. The packets sent back by the receiving end get queued with the same priority as the packets sent by the other party in that direction, so all packets come through but file transfer protocols are made so that there's a "window" one device can send before receiving confirmation that packets arrived, and assuming all packets arrive properly, the window keeps moving at such speed the transfer should at all times be active.

 

This is the theory. 

 

In practice, the download will affect the upload if there are congested devices between you and the destination or if the router throughput is lower than the sum of download and upload.

 

(This is a very simplified post for two reasons. I didn't want to create a tl;dr wall and I don't actually remember all the theory from the top of my head. Might also have some errors in it.)

[schizznick]

TCP packets require an ACK in the opposing direction, so a download packet will need your PC to send a packet via upload back to the source confirming its receipt. This packet is typically small but still necessary, however in most home internet scenarios the upload is much lower than the download. So if you saturate your upload and those acks cannot make it back to the source by what is called the TTL or time to live then the source will resend that packet wasting some download. If your upload is severely saturated this can be detrimental to your download making your internet seem slow or unusable. 

 

Asynchronous technologies still exist, ADSL and Cable Internet are widespread and usually have a ratio of 10/1 so for every 10Mb download you have 1Mb upload. Other technologies such as VDSL and g.fast change that ratio reducing the issue but it still exists. Much of this is a physical limitation. Some solutions such as QOS or COS bits can help in these situations but require some knowledge and equipment to effectively work. Queuing and other similar ideas also help. 

 

Ultimately your upload does affect your download in a very real manner and can make your internet unusable. As a side note I will mention that wi-fi compounds this issue due to it being a half duplex technology.