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From my understanding of networking, how can a single user hog all the bandwidth. Bandwidth is not something that is used. Packets are simply queued and sent on their way as fast as they can no matter their origin. For this example imagine an office with a 45 Mbit/s DS-3. You have the following scenarios.

First assume no one on the network is doing anything. A user, A, downloads a file from a large CDN. This CDN has sufficient bandwidth (multi-Gig lines). The user will max out the line at 45 Mbit/s (assuming no losses or overhead). User A is not wasting bandwidth. He is maxing the line because no one else is doing anything.

Now we have user B jump on. He downloads a file from a crappy Hostgator server. The server has a line rate of 10 Mbit/s. He isn't prohibited from accessing the network and he will not only get a little bandwidth since User A got there first. No! His packets will be queued along with User A's. Naturally the network will slow down User A and User B. For example User A will download at 40 Mbit/s and User B will download at 5 Mbit/s.

If user B downloaded from the CDN User A and B would download at 22.5 Mbit/s.

If 8 users were on downloading from the CDN they would all download at 5 Mbit/s

My point is that no user can take up or hog any amount of bandwidth. If he is maxing out the line he will slow down when other users come on. Am I right?

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closed as primarily opinion-based by David, Xavierjazz, Ramhound, Ƭᴇcʜιᴇ007, Zoredache Feb 8 '14 at 1:01

Many good questions generate some degree of opinion based on expert experience, but answers to this question will tend to be almost entirely based on opinions, rather than facts, references, or specific expertise.If this question can be reworded to fit the rules in the help center, please edit the question.

why is a hostgator server considered "crappy"? – Sickest Feb 8 '14 at 0:35
@Sickest - lol are you a hostgator shill? – bandwidthhog29 Feb 8 '14 at 0:37
Can we get rid if the rant? – Ramhound Feb 8 '14 at 0:52
ISPs don't pay for their connection only based on the total capacity, they often have to pay based on the actual bytes transferred. If one customer is transferring data far beyond all the others, then that customer should pay more. – Zoredache Feb 8 '14 at 0:59
@bandwidthhog29 If someone downloads something and then throws it away, that bandwidth is wasted. If that person makes your download take three minutes instead of two, then you will get annoyed at that someone. If enough people waste enough bandwidth, then money will have to be wasted upgrading links so that people who really need bandwidth get acceptable performance. – David Schwartz Feb 8 '14 at 2:38

There is a level of performance that customers consider acceptable and a level they consider unacceptable. A given network can accommodate only so much traffic before the performance gets unacceptable and either users will leave or costly network upgrades will be needed. So the more traffic a user creates for the network, the fewer users the network can accommodate before its performance becomes unacceptable.

Imagine a network that can accommodate 50,000 average users before performance becomes unacceptable. If you use twice as much bandwidth as average, only 25,000 users like you can be accommodated -- each of you effectively takes up two slots.

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Yes but if that 1 person is maxing out the segment or DSLAM (1% of users using 99% of the bandwidth as they say...), wouldn't he simply slow down when the other users hop on. He's only getting the speed he's getting because no one else is using it. If it wasn't available (other users downloading) he would go slower. – bandwidthhog29 Feb 7 '14 at 23:58
He does go slower, but everyone else does too. They will only tolerate so much of that before an expensive network upgrade is needed. – David Schwartz Feb 8 '14 at 0:02
As David has pointed out that the 'heavy user' will be slowing down everyone. But at the same time, everyone are promised "Up to xMbps speed" but then because of one (or more) heavy users, everyone are never seeing that promised speed and think "this network is crap" and move to a different ISP in which said ISP is losing money. – Darius Feb 8 '14 at 0:14
Reread your post. So you are saying the network is oversold? if everyone with an Xfinity 50 Mbit/s connection actually opened their pipes fully and continuiously no one would get near 50 Mbit/s. It would be more like 0.5 Mbit! – bandwidthhog29 Feb 8 '14 at 0:39
@bandwidthhog29 Yes. Network is ALWAYS oversold. Hence why the 'cheap' unlimited* bandwidth with a TOS saying "If we find you are the top n% bandwidth user, we can decide to throttle your service". Unless you are a business user, paying premium $200 per month with Service Level Agreement, and/or promise of 1:1 bandwidth capacity for minimum download cap. Guarantee of service is expensive. The business needs that guarantee, and they're the one paying the price for it. (It happens to be one of the topic of "Computer Networks" lecture I am currently enrolled in – Darius Feb 8 '14 at 1:25

If user A is continuously using the pipe at full speed, such as seeding a large amount of torrents, then that user is arguably 'hogging' the connection. In every discussion I've seen of in relation to 'hogging' it invariably involves using bandwidth over a lengthy period of time, not a short snapshot in time as your analysis does.

If that network's main purpose is not for the seeding of torrents but some other use, then that user is decreasing the amount of available bandwidth for it's intended purpose. I would consider that hogging.

There are also limits on how many packets each device on the network can queue up, and it's not much. If these limits are exceeded, packets may be dropped which may trigger (tcp) retransmissions, thereby increasing the amount of bandwidth required to do the job had user A not been (mis)using the network or even dropped/failed connections.

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But when user B, C, and D jump on A will not go at full speed any more. A is only going at full speed because that bandwidth is available. If it was not available (since others are using the network) he will go as fast as he can, but still respecting the queued packets of the other users. or am I looking at this wrong? – bandwidthhog29 Feb 8 '14 at 0:00
Yes, you are looking at this wrong. This is more of a policy topic than a bandwidth/networking topic. People pay for networks (usually) for a specific purpose. Someone degrading the ability of using it for that purpose is hogging. Not to mention most 'hogs' use 'download accelerators' or other utilities that establish multiple connections in hopes that they will get multiple slices of that bandwidth whereas others will only get one. Also remember that not all network connections are unlimited, continuous use of that 45Mbit may cause the bill to skyrocket. – yoonix Feb 8 '14 at 0:04
@bandwidthhog29 What you're missing is that not only will A not go full speed any more, but neither will B, C, or D. Bandwidth is a shared, finite resource -- everyone wants some, and everyone has to share. – David Schwartz Feb 8 '14 at 2:20

The ISP is in the business of selling a service: the ability for you to connect to the Internet. As such, they set forth rules (Terms of Service or TOS) whereas they want to get paid for the traffic you sent through their equipment. If one person is constantly sending traffic through their equipment, they can decide to enforce their TOS by limiting your bandwidth. Or they will ask you to upgrade to a different tier with more bandwidth. Remember, your ISP pays their backbone carrier for all traffic going thru, so if one person is constantly generating traffic while on a $25/month plan, the ISP loses money. This is not their business model, so we all end-up paying more for a service, or they enforce throttling to avoid such issues.

Another thing to keep in mind is QOS. A business account will have better QOS (but not always) than a home user. They pay more, thus they get better service. Or so is the rationale. The point of this "answer" is that, no matter what, someone pays for the service being provided. You pay more money...or you get less "service provided" to you.

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