cancel
Showing results for 
Search instead for 
Did you mean: 

Traffic Management Blog

dave
Plusnet Help Team
Plusnet Help Team
Posts: 12,257
Thanks: 306
Fixes: 4
Registered: ‎04-04-2007

Traffic Management Blog

Couple of posts made to the blog today:
http://community.plus.net/trafficmanagement/
Feel free post and questions or discussion.
Dave Tomlinson
Enterprise Architect - Network & OSS
Plusnet Technology
4 REPLIES 4
Assos
Grafter
Posts: 5,880
Thanks: 1
Registered: ‎05-04-2007

Re: Traffic Management Blog

Dave, one thing I don't quite understand, and although it's not directly related to the postings, it is to do with traffic management:
Why the need for rate limits on p2p etc? Surely, all that should be needed to ensure that http etc gets it's fair share is prioritisation, ie you have the priority queues, then when the traffic becomes greater than the available bandwidth surely the ellacoyas could just drop the lowest priority traffic? Am I missing something?
zubel
Community Veteran
Posts: 3,793
Thanks: 4
Registered: ‎08-06-2007

Re: Traffic Management Blog

I read the article about the Belgian ISP the other day, and immediately tried to mail the Belgian organisation responsible.
I'm sure the most techy amongst us know that it is absolutely impossible to detect exactly what traffic is passing across your home broadband connection.
Several P2P programs already include optional end-to-end encryption (Azureus is one) which would defeat this supposed mechanism before it starts.  If they did find a way to decode the encryption, then it would be a few more minutes before someone developed an alternative way.
I believe that ISP's should be treated as transit carriers, and given protection akin to the 'Safe Harbor' legislation in the US.  It has been proven time and time again that any technical measures put in place to cripple, er.. I mean protect copyright holders can be defeated.  DRM is a waste of time (look how long it took to crack Blu-Ray and HD-DVD!), or just plain intrusive (Sony rootkit fiasco).
What is really needed is a change in operating methods for the RIAA/MPAA and their European counterparts.  They need to look at their business model, and adapt it to the changing face of technology. 
Forcing ISP's to run content filtering software is a slippery slope.  First you start with blocking copyrighted files via P2P which will no doubt impact on legitimate P2P uses as Dave mentioned in his blog post.  World of Warcraft and Kontiki are classic examples of this - completely legitimate P2P usage.  Once ISP's have been forced to block this content, what is to stop someone else bringing the case for blocking pornography, (arguably the web's most profitable business) or blocking access to websites based on political content.
I think ISP's should fight this from the word go.  The analogies that Dave posted regarding post and phone are good examples - use existing legislation to monitor traffic as needed, not as a blanket license to interfere.
Barry
dave
Plusnet Help Team
Plusnet Help Team
Posts: 12,257
Thanks: 306
Fixes: 4
Registered: ‎04-04-2007

Re: Traffic Management Blog

Quote from: Assos
Why the need for rate limits on p2p etc? Surely, all that should be needed to ensure that http etc gets it's fair share is prioritisation, ie you have the priority queues, then when the traffic becomes greater than the available bandwidth surely the ellacoyas could just drop the lowest priority traffic? Am I missing something?

The rate limits do two jobs, the first and most important job is to ensure an even spread of the available non-interactive bandwidth between those customers that are using that bandwidth.
For example, let's say there's 100Mbps (made up figure) of bandwidth available for Usenet and P2P usage and there are 200 people trying to download. All things being equal each person would see a download speed of 100Mbps/200 = 512kbps.
But, some people could open up more threads (for example one person downloading from Easynews could open 32 threads) and get more than 512kbps. If you have say 10 people taking 6Mbps each that leaves the remaining 190 people with 40Mbps or 211kbps on average.
In other words there's a disproportionate distribution of the available bandwidth. If we set the rate limit at the speed we expect people to see, so in this case 512kbps, then the available bandwidth is much more evenly spread as everyone gets 512kbps speeds rather than a few people getting much more and the rest getting a lot less.
The second reason is to help guard against packet loss. The way that the traffic management system works is that when a queue is full the traffic starts to buffer and if it can't retransmit the packets before the buffer time expires the packets are dropped. The rate limits help keep the buffered traffic low and thus the packet drops low.
Dave Tomlinson
Enterprise Architect - Network & OSS
Plusnet Technology
dave
Plusnet Help Team
Plusnet Help Team
Posts: 12,257
Thanks: 306
Fixes: 4
Registered: ‎04-04-2007

Re: Traffic Management Blog

Quote from: zubel
I'm sure the most techy amongst us know that it is absolutely impossible to detect exactly what traffic is passing across your home broadband connection.

Even with the traffic management systems we have available to us as an ISP we can't be exactly sure on everything. We can see the protocol, as you can see in the breakdown in VMBU and we can break that down a bit further so in Gaming we can see different games like Xbox live or Unreal Tournament, or in Other we can see DNS or SSH or VPN for example. But these are just protocol splits and don't show anything about the actual content.
Quote
Several P2P programs already include optional end-to-end encryption (Azureus is one) which would defeat this supposed mechanism before it starts.  If they did find a way to decode the encryption, then it would be a few more minutes before someone developed an alternative way.

Indeed, whilst we have a set of signatures to detect encrypted P2P we've no way of telling the difference between someone download Lost or sharing their own open source software.
Quote
I believe that ISP's should be treated as transit carriers, and given protection akin to the 'Safe Harbor' legislation in the US. 

Totally agree.
Quote
It has been proven time and time again that any technical measures put in place to cripple, er.. I mean protect copyright holders can be defeated.

And in many cases it's because the measures are there in the first place that certain people want to break them.
Quote
They need to look at their business model, and adapt it to the changing face of technology. 

Absolutely, the success of services like iTunes shows that people are willing to pay for digital content if done right. One of the reasons people in the UK download American TV shows is because of the delay before they are shown here (or not shown at all). Put them on at the same time and I'm sure you'd see less downloading.
Same kind of thing with films, instead of staggered releases around the world and staggered releases on DVD and PPV TV, etc. do them at the same time. As I suggested at in the blog I'm sure there are people that would be willing to pay a small fee to watch a new film on their TV. My nearest cinema is 10 miles away and they don't exactly have comfortable seats. I wouldn't mind seeing the new Transformers film but I'm not going to the cinema and I'm not going to download a poor quality cam, I'll probably wait until it's on Sky Movies to see it.
The film industry's probably just lost out on revenue from me or people like me who'd probably pay extra for a Sky Movies type service that had films at the same time as the cinema release but probably not lose out on the cinema revenue. With good enough quality, low enough pricing and worldwide symultaneous availability it's certainly going to tempt people away from illegal downloads.
Quote
Once ISP's have been forced to block this content, what is to stop someone else bringing the case for blocking pornography, (arguably the web's most profitable business) or blocking access to websites based on political content.

Indeed, the ISPs' aren't there to be the censors. As you say with one lobby group may want to block illegal downloads another may want to block pornography but what happens when if that happens and the ISP misses something? And where does the censorship end? Would a site reviewing Amsterdam's coffeeshops, or sites about guns be censored for example?
Quote
I think ISP's should fight this from the word go. 

As I'm sure you expect this has stirred up quite a debate on our side and it's something that needs discussion from all parties. I would like to think that before any legislation (or potential legislation bearing in mind the Conservative party are in opposition) a full consultation would be made so they can understand what doing something like this would involve.
Dave Tomlinson
Enterprise Architect - Network & OSS
Plusnet Technology