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In this NPR article there is mentioned 'network neutrality' with very little details on what it actually is or how it actually works. I tried researching it on my own but I get a lot of non-technical explanations of what it is fighting against (essentially metering internet traffic speeds) but I am very confused as to how this works.

My understanding of the internet (broadly) is that user Joe opens up a connection with website npr.com via the http protocol (after some dns work) which sends and receives data to and from npr's server utilizing both npr's and joe's upload and download speeds.

Where is the throttling occurring? Am I missing a crucial step? Is the 'traffic' being throttled 'on the way' to the client/server somewhat like a tollbooth at the ISP level?

The NPR article brings up the example of how one website could pay to have their traffic go to the user faster. I just dont understand this because isnt all my incoming traffic maxed out at whatever my download speed is? Further, isnt the server maxed out at whatever their upload speed is?

For example, if I try to send 1mb of data from a server (www.mysimplesite.com) with an upload speed of 1mb/s to a client (joe) who has a download speed of 1mb/s would this transfer not happen in the same [theoretical] time as a server (www.thesuperubersite.com) with an upload speed of 2mb/s?

I fail to see how any server can pay to have their content 'reach the user faster' if it is the client who generally is the speed limitation. From a technical perspective, how would this work? I'm also not looking for an analogy or opinions.

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Net neutrality = ISP owns superhighway and charges people a monthly fee to drive their own car anywhere on it. The new FCC rule proposal would permit ISPs to build a dedicated lane for you to go to McDonalds or WalMart to avoid congestion on the superhighway, but McDonalds and Walmart also pay the ISP for that lane. The US FCC has too many former Comcast and Verizon cronies working there these days. –  Mike Pennington May 15 at 14:24
    
It's understandable that you think that the client is the limitation, because at this point in time that really is the case. The ISP and the website you want to visit both have much more bandwidth than you right now. The problem if net neutrality goes down the drain is precisely that that will no longer be the case. Without it, the ISP would be free to reduce the amount of bandwidth allocated to site-that-wont-pay-us.com so that traffic cannot reach it. I.e. even though you have 3mb connection, the site only has 0.5 and that's already taken by other users. No connection for you. Cont... –  BinaryTox1n May 15 at 18:28
    
Cont... This works because you don't have a direct connection to the site you want to visit, you have to connect to the website's server via a network provided by your ISP. That's where all the slow down happens. –  BinaryTox1n May 15 at 18:29
    
@BinaryTox1n, so what you are saying the ISP will impose a tiered pricing structure for their services? How is this any different than what already happens? The client pays for a download speed and the server for an upload speed. Neither pays for a particular speed for a particular connection though, right? –  Matthew Peters May 15 at 19:34
    
@MatthewPeters My description was a bit simplified. Currently we do pay for an amount of bandwidth. However, due to the nature of internet traffic, ISPs sell more bandwidth than they actually have. If they were required to have enough bandwidth to cover all of every users allotted bandwidth at once this would result in a highly inefficient network (no one uses all their bandwidth all the time). Therefore at least sometimes there is more traffic on the network than the network can handle(everyone is using their full potential). Since someone has to get dropped it will be the one who didn't pay. –  BinaryTox1n May 15 at 19:49

8 Answers 8

up vote 11 down vote accepted

Network neutrality effectively governs how providers can handle traffic. This is pretty broad in nature. It has upsides and downsides, although the downsides are pretty drastic.

If net neutrality were to fail, you would see things that benefit that provider flourish; along with anyone that has the budget to support them. The problem is: imagine if Verizon decided it didn’t want any VoIP traffic, other than it’s offering, to traverse it’s network. That would technically be doable, just not likely. Other Tier 1 providers would be free to do the same, so a mutual agreement would probably ensue.

If net neutrality were to succeed, you would see an even internet marketplace. One of the most recent net neutrality issues that’s come forward has been between Netflix and Comcast. Most would call this extortion, as Comcast obviously makes up a large portion of Netflix’s customer base. This eventually caused Netflix to raise it’s prices (however slightly), thus, changing a big portion of their business model (cheap internet TV). Situations like this wouldn’t legally be able to take place.

Where is the throttling occurring? Am I missing a crucial step? Is the 'traffic' being throttled 'on the way' to the client/server somewhat like a tollbooth at the ISP level?

When you think of throttling, you should be thinking quality of servicing. Most points of the internet work on the principle of oversubscription, which makes more effective use of infrastructure. So even if you have a 1Gb/s internet connection, Tier 1 internet provider’s backbones aren’t capable of sustaining 1Gb/s for millions of customers.

I fail to see how any server can pay to have their content 'reach the user faster' if it is the client who generally is the speed limitation. From a technical perspective, how would this work? I'm also not looking for an analogy or opinions.

A provider has the ability to service packets as they see fit. At micro-scale, imagine you have 2 users connected via a 100Mb connection to separate providers. Each provider is peering through a 100Mb connection to one another.

If either provider decides those users are less important than any other customer they have, they can shape that traffic to be less important than anything else, meaning they have the capability of being dropped first if there isn’t enough bandwidth to support them.

It would also be good to point out that those packets may not make it at all. It is entirely possible to drop packets altogether if they fall outside the threshold those providers provisioned.

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So all of this can boil down to whether an ISP should be allowed to what, shape its traffic or shape its traffic according to who pays more? –  Matthew Peters May 15 at 20:00
    
@MatthewPeters Exactly. That is the entire gist of it. –  Ryan Foley May 15 at 20:02
    
I assume an ISP already does shape its traffic, so could you explain (in your answer) how that works (doesnt have to be super detailed) and how it would be different if net neutrality is not maintained? –  Matthew Peters May 15 at 20:05
    
@MatthewPeters, note that it's not just the client's ISP and the server's ISP; it's also the "ISP of the ISPs" (ie. Tier 1/2 carriers who connect the ISPs together). If any of those networks between client and server favor, say, Youtube traffic over other video-sharing sites, then your experience on those "other" sites is going to suck. –  Alex D May 15 at 21:01
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Also note: As you say, it's natural that both clients and servers who pay their ISP more get more BW. But it is not natural that the server has to pay the client's ISP to avoid having their traffic throttled. It is also not natural that the big carriers ("ISPs of the ISPs") should start "double-dipping" by collecting payments not only from their customers (ISPs), but also from their customers' customers (companies which use the ISPs' service and want to avoid having their traffic throttled when it passes through the carrier's network). –  Alex D May 15 at 21:06

This is a large issue with many nuances, and one that has valid concerns on both sides of the issue.

To get to the heart of this matter, you need to understand that the Internet is not a single entity. It is made up of a large number of individual networks that are inter-connected.

A consumer pays an ISP to connect their personal network to the ISP's network. The ISP may be paying another service provider (often more than one) to connect to their network or the ISP could be a major carrier themselves (i.e. providing large bandwidth connectivity over large geographic areas). These larger carriers interconnect (or peer) with each other at multiple peering points (data centers where they each have a presence). The services to which the consumer wants access are either consumers themselves or may operate large networks of their own.

The other concept to understand is that the internet was largely built on an "over-subscription" model to keep costs low. What this means is that if a ISP/carrier had a certain amount of network capacity, they might sell 10-30 times this amount of bandwidth to customers, knowing that customers don't use all the capacity they pay for 100% of the time.

With "always on" internet and consumers using their bandwidth more (both total and average), this ability to over subscribe has been significantly diminished. Since ISPs/carriers are looking to expand their network capacity and don't want to increase costs to customers (who may choose to move elsewhere if they do), they are looking at other ways to increase revenues to offset the additional costs.

Some of the ways that parties are looking to increase revenues involves treating traffic differently based on the source and/or destination of the traffic. The intent of net neutrality policies would be to prevent providers from treating traffic differently, no matter where it is sourced or destined.

So let's use an example to illustrate some of the issues. To get information from a service such as Netflix a request goes from the consumer's network, to their ISP's network, possibly to one or more carrier networks (for this example, let's say A and then B), and finally to the Netflix network. For simplicity, we will assume the reverse path is the same.

Consumer <--> ISP <--> Carrier A <--> Carrier B <--> Netflix

If both the consumer and Netflix were connected to the same ISP/carrier, there would be no issue as the ISP/carrier would be getting paid by both parties. However in the example I provided, the ISP is paid by the consumer and Carrier B is paid by Netflix. Carrier A isn't compensated directly by either the consumer or Netflix, even though it may carry the data further geographically than anyone else along the path.

Let's look at a few potential cases that already have their seeds in real world practices:

1-Carrier A

Carrier A is passing a lot of data that isn't originated or destined for someone on their network. They are not getting paid by either party directly.

Carrier A feels that since there is a large amount of data from Netflix passing through it's network (neither sourced or destined for their network), it feels that they should be further compensated for this, and wants Netflix (or possibly Carrier B) to pay them for this traffic.

Netflix doesn't see a need to pay Carrier A, so Carrier A looks at some of the things it can do (to reduce costs for running their network, make their network better for their customers, and/or make it more desirable for Netflix to pay them):

  • They can slow down Netflix's traffic unless they pay.
  • They may choose to prioritize their traffic and anyone else's that chooses to pay them, leaving Netflix and other traffic to suffer (mainly during peak times when excess capacity may be low).
  • They may route Netflix traffic over older/slower infrastructure to leave newer/faster infrastructure for those who paid them for it.
  • They may refuse to carry any Netflix data, making it traverse over a longer route (i.e. instead of Carrier A data now must pass through Carrier C, Carrier, D and Carrier E before getting to the ISP).

2-ISP with Netflix

The ISP on the other hand, while getting paid by the consumer notices that the vast majority of the traffic is coming from outside it's network and going to the consumer. The increased bandwidth usage means they need to expand the capacity of their network, but they don't want to increase prices to consumers, and believe Netflix should compensate them.

This results in the same situation as above, with the ISP thinking along the same lines as Carrier A.

3-ISP with Consumer

The ISP decides to offer a "premium" service to consumers, if they want to pay more. This would give the premium consumers' traffic priority during peak times when the ISP's network might be short on capacity. Non-premium customers may notice increased latency and lower speeds during these times.

In my mind, this is an artificially created revenue stream, much like some ISPs that charged a premium for "always on" DSL/cable service. They are creating a perceived need that isn't really necessary so their customers feel better about paying more for the service. Basically, it allows them to raise their rates in a way where the consumer feels better about what they are paying for rather than getting upset.

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ISPs made an assumption about traffic per customer. The economics of that assumption are changing with Netflix / Youtube / etc. However, it's a bad idea for the FCC to claim that allowing double-ended billing (which is what the new proposal does) helps. If the customer is sucking too much content, charge them more... Ultimately I think the "internet fast lane" suggestion is just a smoke screen for ISPs to justify prioritizing their own on-net video services. Many of the big players built huge MetroE rings in-part banking on profit from their on-net video-on-demand services. –  Mike Pennington May 16 at 0:50
    
I'd also add that your argument about Carrier A having no skin in the game seems a bit flawed. Carrier A charges Carrier B for transit. When you sell transit, it's pretty-much a given that the transit pipe is going to run near capacity, if Carrier B has bgp skills + large customers. –  Mike Pennington May 16 at 0:57
    
@MikePennington, I agree with you. As I initially mentioned, this is an issue with many nuances, and trying to hit every point in any detail would make this into a short book at the least. The very same reason I left any sort of peering/transit contracts out of my answer...which I allowed for but didn't discuss by saying they received no direct compensation from the consumer or Netflix. Any sort of an agreement between Carrier A and Carrier B would be an indirect form of compensation from the consumer and/or Netflix. –  YLearn May 16 at 1:03
    
I'm having a lot of trouble understanding what the valid concerns are on the other side of net neutrality. What is the difference between all of the traffic coming from netflix or from distributed ptp traffic that traverses across A and B? They are both compensated already through peering agreements. –  Bradley Kreider May 16 at 19:23
    
@BradleyKreider, great question. Briefly, peering agreements were founded on the idea that entities were peers, with data flowing between networks roughly equally. As this has changed peering agreements have changed and these changes are negotiated. Often in negotiations, both parties compromise and neither feel they got what they wanted. In this case they may feel like their compensation is not sufficient and be looking for alternative revenue. Or they may simply be looking for additional revenue to improve their network. In the end, they are businesses and additional revenue is a good thing. –  YLearn May 17 at 1:21

Network neutrality is the principle that an ISP must treat all network traffic equally, regardless of source or destination. This means that, for instance, if your ISP provides a VoIP telephone service, or a cable TV service, they can't prioritize their own offerings over third party service. If they are allowed to prioritize their own services, then they can basically force their customers into their own non-internet offerings, simply by degrading the performance of their competitors. The flip side of this, which is what happened to Netflix, is that, with network neutrality, the John Smith pays their ISP, and Netflix pays their ISP, and that's it. Without net neutrality, John Smith's ISP can demand payment from Netflix in order for Netflix to be able to provide their service to John Smith. Basically, John Smith's ISP gets paid by both John Smith and Netflix, even though Netflix is already paying their own ISP bill. The ultimate extreme of the collapse of net neutrality is that an ISP customer in the US with relatives in England would have to pay both their US ISP, and the ISP in the UK, and the English relatives would have to pay both the US and UK ISPs, also. Add in the ISP of every other person or company in the world that you might want to communicate with, and you'd be paying hundreds of bills every month, just to be able to use the "global" internet. Basically, the ISPs want to take the internet back to the late 80s, where you had Compuserve, AOL, and a bunch of other "online services" that didn't actually connect to each other. So, Compuserve customers could only access Compuserve services.

The technical part of doing this is actually remarkably easy. ISPs can prioritize traffic right now, for various reasons. For example, VoIP traffic could be prioritized above email traffic, since VoIP requires much lower latency connections to prevent dropouts. This is perfectly valid and legal, even with net neutrality. It's basically just setting a rule in a router, that, say, 50% of bandwidth should be used for VoIP, 40% for web browsing, and 10% for email. But, this prioritization can also be done based on source or destination. This is what the ISPs want to do. So, traffic from Netflix could be set to only use 10% of Comcast's bandwidth, unless Netflix pays Comcast money, despite the fact that Netflix is not a customer of Comcast. Meanwhile, Comcast's streaming video service could be set to use 90% of bandwidth, basically killing Netflix on Comcast's network.

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Each ISP can control the end-to-end experience (the speed, latency) by selectively applying Quality of service (QOS) and routing decisions based on the traffic source/destinatoin.

So an ISP could provide premium (higher QOS, over higher cost/faster/fewer-hops links) service to/from service providers that pay a premium. So if Netflix pays, and gets the premium, but (for example) Hulu didn't... customers would start thinking "Hulu sucks. Netflix if fast!" when in reality, the invisible-to-the-user ISP service is affecting performance.

The big issue people have (I think) is that it means that (for example) the big players (e.g. Netflix) can spend big money for premium ISP through-carry and make it hard/impossible for small players (netflix startup competitor that might come some day) to get the same level of service to the end users.

To date, the Internet has been one big level playing field "in the middle"; A "neutral network."

(...and see Ryan Foley's answer which has more technical clarity than my attempt.)

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The throttling most oftens happens at the carrier that is near the client, but can potentially occur within any transit carrier or non-transit carrier. Throttling actions can occur on a particular pattern of traffic from Layer 3 to Layer 7, and can occur in many ways, whether it is lowering the priority of the traffic in queue, imposing absolute bandwidth limitations, reducing the share of overall bandwidth that the traffic has available to use, or outright blocking the traffic altogether. Throttling most often occurs when the service integrity of a carrier is threatened by a particular pattern of overwhelming usage. First, the overwhelming traffic pattern that threatens overall user experience is identified, then the best manner of throttling is determined that does not further threaten the service of the overall customer base.

Patterns of overwhelming usage is a common concern of any service provider, and many businesses maintain a policy based on the likelihood of the event. For example, rolling brownouts and customer notifications when power usage spikes during peak hours, or lane closures and traffic redirection during large attendance at entertainment venues.

The client experiences throttling by receiving a particular service at a lower speed than they expected, but may still have the total speed available for any other service. For example, a client may have a 16Mbps download speed, and require 16Mbps to receive a 1080p stream at 30fps from a movie streaming service. Unfortunately, a large number of other users, although a small percentage of the user base, request the same, which saturates the ISP's link into Level3, forcing redirects to route around, and threaten saturation of the ISP's other link into Hurricane Electric. This saturation event threatens the entire service level of the ISP, and the traffic is singled out as the primary culprit as 4% of the user base are consuming 85% of the bandwidth. The ISP then rate-limits the particular pattern of the stream by hard-limiting the total bandwidth availabe to that traffic across the link to Level3. The streaming player detects the rate-limit that 16Mbps is no longer available, and downgrades the connection from 1080p to 480p @ 30fps, reducing the overall traffic request of the client to 3Mbps. The ISP no longer experiences the link saturation event, but maintains the hard rate-limit to mitigate the risk of a repeat event based on the same traffic.

The ISP then contacts the movie streaming service and proposes adding a new peer link to Level3 or providing a caching host connection internal to the ISP's network to avoid repeated saturation issues. Due to the costs of adding the additional peer link on account of a single service overwhelming the ISP's network, the ISP proposes to share the costs of additional infrastructure with the movie streaming service.

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You have a great example but could you explain what 'level3' is as well as the layers (3 and 7 in particular)? –  Matthew Peters Jun 10 at 2:09
    
Level3 refers to the name a large ISP. The author seems to have a specific network in mind; I disagree with his conclusions about the need for billing content providers beyond the cost of the content provider's access circuit. –  user5025 Jun 12 at 13:08

Netflix and other providers often put servers within an ISP's area so that it reduces the amount of traffic traversing the networks. So a New York netflix user does not need to cross all the networks between it and Sanfran where the main netflix servers are (hypothetically) Allegedly some of the ISPs are not allowing the servers within their network to deliberately cause a traffic problem and say it needs to be paid for.

So even though Netflix etc don't have servers in the ISPs area they will still have to pay to access the customers. If the netflix server was at the end of your street it would not have to block loads of switches and routers in between.

In your example your simplesite.com can currently send unlimited amounts of traffic to anybody and you don't need to pay the ISPs inbetween. They all allow each others traffic to move across the networks. What the ISPs are looking to to is double charge both your website and the customer.

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This doesnt really explain how in technical details. –  Matthew Peters May 15 at 17:54

The internet is not far from becoming just like any other utility (water, power, etc) -- something you assume everyone needs and has a right to have.

Net Neutrality would make it so the ISP (Internet Service Providers) can only provide you with a link to the Internet. Nothing more. Which is a GOOD thing. Just like your power and water company, they provide you with power and water. They don't care whether you use a refrigerator from Kenmore, or Sears, or GE, or Whirlpool, etc.

The current bill would allow ISP to charge premiums for faster access to certain services/websites. Something like a faster download rate when browsing youtube, or watching videos on netflix, etc.

The best comparison is to continue comparing the Internet to a utility service. What if your power company could charge you more to ensure a better power stream when you are using (for example) General Electric devices (your fridge, your toaster, etc). But, what if you own a Kenmore refrigerate, are you out of luck? Left to accept just the bare minimum your power company will give you in so far as power.

People would be outraged if the Power Company all of a sudden imposed fees to power certain company's devices, while trying to avoid blame by stating that you always have the option to not pay the fees for a lesser service.

Replace the "power company" with "your local ISP" and replace "a company's electronic devices" with various online businesses (ebay, netflix, youtube, amazon VoD, etc). The problem is, once they start "charging a premium for certain sites", its only a matter of time before all the remaining sites end up having terrible service. Which takes your choice away, as the consumer, because you will be forced to choose (and pay more for) the service that your ISP happens to support.

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This also doesnt explain how an ISP can/does regulate how fast a consumer/client can access data... –  Matthew Peters May 15 at 17:56

Split traffic based on users

You have three sons in their teens who game like idiots. They use so much bandwidth that you decide to take a second high speed cable connection. You buy a nice Draytek router that can handle two internet connections into one network, and which can decide which computer connects to what network, based on a set of rules. Now you have the following situation:

  • You, your wife and 8 year old daughter use an 8mbps ADLS connection. This keeps it safe for your daughter, and you can limit her access.
  • Your sons have their own computers, which use a 50mbit cable connection via the same router.

Split traffic based on type of usage

So far nothing new, and this is comparable with two different households, one of them with a fast connection. But now you change the setup of the router, and based on the kind of traffic or the kind of websites that are used, you decide to use ADSL or cable.

  • Gaming, Youtube, Netflix go through fast cable
  • Facebook, general netbrowsing, gmail go through ADSL

Given enough users, ADSL will feel "throttled". In fact it is not throttled, it's just a slower channel. Given enough speed, cable will never feel throttled. So traffic is not throttled, it's just directed through a channel that cannot handle the speed that you would expect, compared to using cable.

Why is this bad

You may think that this is not such a bad thing. In my example I'm talking about Facebook and Gmail going through the slow connection. That will not happen. Facebook will pay for speed, just like Google and Microsoft. They have the money. Small firms and sites don't have that money. They will not pay, visitors get annoyed with the slow connection, and stay away.

When I google for something like sneakers, I will click several links. Some will take 20-30 seconds to open and before that the page is blank. Many times I close the tab and choose another link. This will get worse.

Facebook has its own server farms that serve superfast. I use a cheapass 10 euro a year provider and just one wordpress page can take 30 seconds depending on other traffic on that server.

To be honest I still don't see how this is different, and I don't know what the side effects will be. So I can't tell you why this will be more problematic than using (and paying for) a fast or slow server.

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