I tried googling around but could not find anything. Let's say an ISP rates a connection as 250Mbps down and 250Mbps up. In theory, does that mean you can saturate both simultaneously? In other words, is the connection capable of 500Mbps? (250 down + 250 up at the same time)
-
SpinRite v6.1 Release #3 Guest:
The 3rd release of SpinRite v6.1 is published and may be obtained by all SpinRite v6.0 owners at the SpinRite v6.1 Pre-Release page. (SpinRite will shortly be officially updated to v6.1 so this page will be renamed.) The primary new feature, and the reason for this release, was the discovery of memory problems in some systems that were affecting SpinRite's operation. So SpinRite now incorporates a built-in test of the system's memory. For the full story, please see this page in the "Pre-Release Announcements & Feedback" forum.
/Steve. -
Be sure to checkout “Tips & Tricks” Dear Guest Visitor → Once you register and log-in please checkout the “Tips & Tricks” page for some very handy tips!
/Steve. -
BootAble – FreeDOS boot testing freeware
To obtain direct, low-level access to a system's mass storage drives, SpinRite runs under a GRC-customized version of FreeDOS which has been modified to add compatibility with all file systems. In order to run SpinRite it must first be possible to boot FreeDOS.
GRC's “BootAble” freeware allows anyone to easily create BIOS-bootable media in order to workout and confirm the details of getting a machine to boot FreeDOS through a BIOS. Once the means of doing that has been determined, the media created by SpinRite can be booted and run in the same way.
The participants here, who have taken the time to share their knowledge and experience, their successes and some frustrations with booting their computers into FreeDOS, have created a valuable knowledgebase which will benefit everyone who follows.
You may click on the image to the right to obtain your own copy of BootAble. Then use the knowledge and experience documented here to boot your computer(s) into FreeDOS. And please do not hesitate to ask questions – nowhere else can better answers be found.
(You may permanently close this reminder with the 'X' in the upper right.)
If you are on a DSL connection, the available bandwidth is normally split between the directions, so theoretically, a 250/250 connection should be able to support 500mbps of traffic. Certain frequencies are allocated to each direction. However, whether your end device ( modem/router) can handle that bandwidth at the same time may be a different issue.
Slow speeds are easy to achieve. Faster speeds are more difficult because your devices need to be fast enough to actually receive and process data at the same time as it is generating and sending data. For example, lets pretend you're using a PC to watch some 4k video while you're also uploading a large file. Your PC will be taxing the network card to handle all the data in and out, while also stressing the video card to decode and present the video and working your HDD or SSD to load the data to send for the upload. All that happens under the direction of the OS and thus the CPU which is intimately involved with it all, so is kept busy as well. If your PC is not up to spec, it may suffer slowdowns and that will show up as back pressure on the network, slowing it down.
Another part of the equation is who you're talking to. If the server on the other side of your connection is overwhelmed, it may not keep up either, and then it won't matter what your PC can do, it can't force more speed out of a slow peer.
Another part of the equation is who you're talking to. If the server on the other side of your connection is overwhelmed, it may not keep up either, and then it won't matter what your PC can do, it can't force more speed out of a slow peer.
This is a theoretical question that assumes no other limitations. In a perfect world, can both up and download speeds the ISPs be achieved simultaneously?
To make it simpler, let's say you're paying for 10Mbps down and 2Mbps up. Can you upload a large file at 2Mbps at the same time as downloading large files at 10Mbps without either the up or download speed being affected by the combined bandwidth?
In other words, if I'm paying for 10 down and 2 up (or whatever), does the ISP allow for both to be maxed out at the same time without taking away from one or the other?
The question stems from wondering what the ISP is capable of. Nevermind other potential limitations on the user's end or anywhere in between the user and the ISP. When I'm paying for a certain bandwidth, is the ISP giving me the ability max out both at the same time?
To make it simpler, let's say you're paying for 10Mbps down and 2Mbps up. Can you upload a large file at 2Mbps at the same time as downloading large files at 10Mbps without either the up or download speed being affected by the combined bandwidth?
In other words, if I'm paying for 10 down and 2 up (or whatever), does the ISP allow for both to be maxed out at the same time without taking away from one or the other?
The question stems from wondering what the ISP is capable of. Nevermind other potential limitations on the user's end or anywhere in between the user and the ISP. When I'm paying for a certain bandwidth, is the ISP giving me the ability max out both at the same time?
Last edited:
I don't know if any of you ever deal with this, but sometimes it takes me a few revisions before I ask the right question. 
My last post, I finally started to articulate what I actually wanted to know, which helped me refine my google search terms and I did find an answer, which @AlanD pretty much hit on. Standard Ethernet now is full duplex, with separate download and upload channels, each using their own copper strands in the ethernet cable. So in theory, each direction should be capable of its full speed simultaneously.
Sorry for the confusion in my initial question.
Here is the thread where I got the info, if anyone is curious:
My last post, I finally started to articulate what I actually wanted to know, which helped me refine my google search terms and I did find an answer, which @AlanD pretty much hit on. Standard Ethernet now is full duplex, with separate download and upload channels, each using their own copper strands in the ethernet cable. So in theory, each direction should be capable of its full speed simultaneously.Sorry for the confusion in my initial question.
Here is the thread where I got the info, if anyone is curious:
Yes. They are theoretically two completely different streams of data. Without realizing it, what you're actually asking is if the channel is half-duplex or full-duplex. All modern networks (that are not for communicating into Space (i.e. NASA)) are full duplex.
It also needs to be made clear that your ISP is making a promise with a HUGE caveat. If you check their terms, it will invariably hedge by saying something like this (from the Bell Canada terms found here):
My read on this is them basically saying: We configured our network to meet the promise we made to you, but we don't have full control, so best effort is all you can expect.
Generally your ISP only rates (Up to) meaning at the best of times this is what you might get. I believe all cable systems are not symmetric meaning that the download speed is always way faster than upload. 1 gig download may only have 50 meg up. I have 1 gig fiber which is supposedly symmetric and I get 900 Meg down and most time 700-800 up. This is OK with me as I upload lots of data. If you need upload speed, you will only get this with fiber.
This is the way internet is most commonly used anyhow. On my home connection, which is 250/25, over 92% of our total bandwidth is downloading. At work, with a symmetric fiber connection and lots of VPN users, 85% of our total bandwidth is still downloading. It's fascinating to look at bandwidth graphs in the firewall. You'd think with a symmetric connection, you'd see much higher upload bandwidth, but it's still only 15% of the total.
I think the rationale behind split speeds is that in a normal home situation, the bulk of the traffic will be downloading, whether video files, or web pages, full of content. The upload will tend to be restricted to small requests, e.g. get me Google, or get this file.
In an office situation, you might expect it to be more balanced, but even then, people will often be downloading more incoming email than sending outgoing mail, as well as the files/web page imbalance. Even with lots of VPN usage, the incoming traffic may be limited by the uploading speeds at the far end being far lower than the downloading speeds.
In an office situation, you might expect it to be more balanced, but even then, people will often be downloading more incoming email than sending outgoing mail, as well as the files/web page imbalance. Even with lots of VPN usage, the incoming traffic may be limited by the uploading speeds at the far end being far lower than the downloading speeds.
I do regular backups to the cloud of photos, large videos and a 4 Gig encrypted file so for me the 1000/1000 fiber connection is wonderful and why I went to fiber as soon as I could. It takes a really really long time to backup a 4 Gig file if your upload speed is only 50Meg. I would never go back to cable. My use probably is not typical however.
In our business, the bulk of the outgoing traffic is over port 443, followed by VPN and then email (at least when there are large file attachments). Our VPN maxes out at around 9Mbps up and down even with more available down/up bandwidth. OVPN is slow, and with encryption and hash algorithms cranked up, that's as fast as it'll go.
Hello
I used to work for one of the big carriers, however not in the ISP group. However - here is a basic way to think about this. Yes, you get full access to the speeds that are advertised AND that actually is capable at your location. HOWEVER - you need to think about the protocols in effect for data communications. There are lots of control packets used along the way. So You send me five packets, and I will ACKnowledge them back to you and tell you to send more. These protocols (such as FTP, email, http web browsing). These have a lot of syncronization involved to ensure that the packets are accurately transmitted from you to me. To do that, I must use the path back from me to you, and utilize SOME of that bandwidth. Therefore, you can also consider that the lack of upload speed may restrict your download speeds depending on how "chatty" the protocol is. Connectionless protocols like UDP - they don't care about quality. SEND AND PRAY! Audio and Video transmissions can be setup this way - and they may make sense, especially for something like IP Television, where we are sending a LOT of packets to the TV over the internet. A glitch here and there may not be too bad. I cannot vouch for the quality of this article I just searched for on the Internet, but this provides some background for you on how to think about this process. https://www.baeldung.com/cs/connection-oriented-vs-connectionless-protocols
Best of luck!
Let me know if you get this message, btw? I don't want to write back unless I know you have this message - or I may have to send it again! (LOL)
Chris
