Child Item

Site Totals

61376 Questions Answered 267 Categories

Uploading degrades download if done concurrently?

If I purely download or upload, the speed is fine with the 20/5 plan.

However I noticed that if I try to download while upload, the download speed becomes slower than the upload speed. (like 2.4mbs instead of 20mbs)

I only have FIOS for 2 weeks.

On a side note, I am getting static on the phone at times.

Comments

mattheww50

The static on your telephone is meaningless. TV, Internet and Phone are different wavelengths on the fiber, so there is no interference among them.

The loss in performance is probably more related to your computer. It actually does take CPU cycles to drive the ethernet board/port. So the time spent setting up an outbound packet, is time that cannot be spent processing an inbound packet.Traffic in one direction does indeed create traffic in the other direction (ack's), so if one direction is much faster than the other, the faster directions is likely to end up being slowed down as you start to load up the slower channel.

Pyao

1. I didn't have the static problem prior to FIOS and I had Verizon Freedom package as well.

2. I have a Q6600 Quad core CPU and it's definitely not a factor on the CPU. It's connected by Ethernet to the router (not wireless). The ethernet port is to set Full 100. Vista x32.

Thanks.

ShiftyBW

Just because you have four cores does not mean that the processing of inbound/outbound packets will be done on all the different cores at an optimum speed, so that's meaningless. Downloading while uploading will always be slower because of the amount of internet traffic you're creating by doing it. As far as my guess goes, the advertised rates are separate top speed listings, not what you would get by doing both at once. Your pipe can only handle so much data going back and forth at once.

Pyao

I highly doubt it's the problem of the NIC or CPU. This is a gigabit NIC, and it's supposed to handle 1 gigbit at full duplex 1000/1000 (assuming 40% overhead, 600/600). With FIOS we are talking about 20/5.

Does anyone else experience this issue, or if they are NOT experiencing the issue when uploading and downloading concurrently?

It would make 20/20 a lot less useful or even problematic when you are uploading, your download speed is reduced to 3 mbit...

philhu

n one message you say you are connected at '100 Full'

Then you say in another you have a '1GB NIC' so it does 1000 in and out.

You obviously do not know network technology.

First, if your '1gb nic' is plugged into a '100 Full' port, then 100 mb/s is the max you can get in each direction.

Second, you cannot reliably go above 65% or so of your bandwidth speed without sever packet loss and resends, so that is 65 mbps

Third, the packet ACKS *WILL* slow down downloads, since they go on the other line, acks in go on the out and acks out go on the in. Ethernet

sends packets of 1513 or so bytes per packet, and then sends a smaller packet as an ACK. Packets can come across TCP/IP out of order requiring

resends, etc. So alot of down traffic will cause up traffic resends.

About your static. Call Verizon about that. That definitely is a problem. Probably a loose red or green wire in the ONT.

Message Edited by philhu on 12-31-2008 08:41 AM

cprgolds

Pyao - there are a zillion things that can affect your upload and download speeds.

Think of your FIOS connection as a pipe (and one with a pretty big diameter). It's up to you (and the people at the other end of your connection) how you use the capacity.

How are you measuring these speeds? That might be part of the problem.

Pyao

I am in IT (software not hardware). I was just saying it's a 1gig NIC, and someone said it's because of NIC that couldn't handle 20/5... It's 1gig NIC connected to router at 100 full duplex.

So even at 50% efficiency, I should be able to do 50/50 across the network to another computer right? So let's rule out CPU or NIC being a factor (I've also tried MTU 1500, 1492), ran FIOS optimizer for 20/5.

The test is done via FTP's internal kb/sec and also external bandwidth monitoring tool.

When doing FTP straight download, I can get 20mbs.

When doing FTP straight upload, I can get 5mbs

When doing FTP upload and download at the same time, my upload gets 5mbs, but my download becomes about 4mbs. I just don't think that's how FIOS should be behaving and I haven't heard about this "condition" while waiting for FIOS to become available.

Can one of you try to see if you can get your concurrent FTP at 10/2 or 15/5 or 20/20?

Message Edited by Pyao on 12-31-2008 06:13 PM

engfant

You really don't know anything about how things are rated for someone claiming to be "in IT".

BEST CASE SINERIO is what is printed on the equipment...

I'm not going to bother cause you clearly just posted on here to stir it up but your understanding of "IT" is amatuer at best. It's slow for the same reason a 10year old dedicated T1 line will destroy any comsumer class internet connection claiming to be "gigabit" or alike.

Pyao

I am asking for somone to test the scenerio that I have described, and either you can't comprehend what the issue is, can't follow the thread discussed, or have not needed to transfer bi-directionally.

If FIOS can not transfer at 20 download and 5 upload concurrently, that means with the 50/20 plan we won't be able to transfer 50 down, and 20 up concurrently.

Child Item