In the US, Comcast is presently using what is referred to as ‘protocol agnostic’ filtering‘ – effectively, if you use the full amount of bandwidth that you are paying for for more than a few minutes, they decrease your available bandwidth for a while. This was, in part, a reaction to their sending RST packets to BitTorrent users – these packets would ‘kill’ connections that individuals had with other P2P users, but were also catching some other programs in the crossfire. What’s more, they were using a technique referred to as ‘packet forging’, which is involves changing packets in-stream. After a substantial amount of public criticism and backlash, Comcast stopped using their DPI equipment for this purpose and instead shifted to using them for protocol agnostic filtering.

Let’s turn to Virgin, who is currently implementing protocol agnostic filtering, but there are rumblings that the way that they’ve deployed it may not be the best solution to combatting what is perceived as the real problem: BitTorrent traffic. From a DSLreports article:

[A] customer on Virgin’s 10Mbps/512kbps “L” tier loses 75% of his throughput for five hours should he download more than 1200MB between 4 and 9PM. (Source)

There are several issues with this kind of agnostic filtering.

1. There are questions of whether or not customers actually have any idea what a gigabyte of data is in real terms (i.e. not ‘how many emails can be sent’ but ‘how many minutes of Hulu does this amount to?’).
2. Given that people are increasingly turning to digital distribution networks, such as iTunes, to download movies and TV shows, there is a real worry that such ‘agnostic’ filtering will affect people who are engaging in 100% legal, non-infringing actions. Filtering the traffic of these individuals means that you are simply punishing them from taking advantage of: (a) the services they believe they are paying for; (b) for using digital distribution streams – the same streams that telecommunications companies have been trumpeting as the future for several years.
3. It suggests that there is something permissible with punishing customers for using the ‘net during prime times – imagine if during the hours of 4-9 cars slowed down to ‘mitigate traffic congestion’. I think that there would be some very serious problems with doing this in the analogue domain, so why do we let ISPs do it in the digital domain?

Now, how will BitTorrent traffic be identified? I would wager that packets and traffic flows will be monitored, likely using middleware devices like Procera’s PacketLogic PL10000. Before we use these devices to identify and punish P2P users, however, maybe there is a way of using them to address issue one from the above list. I’ll note up front: this is arguably a violation of network neutrality principles.

Rogers presently uses DPI equipment to inform their customers when they are reaching their monthly data caps. The problems, as typically outlined, with this strategy are twofold:

1. It’s creepy that your ISP is modifying webpages, inserting a banner ad (effectively) at the top of a webpage that you are visiting.
2. It upsets ‘owners’ of the webpages that you are visiting, because it can upset how they have configured webpages to display ads. Rogers, in effect, threatens their revenue streams.

At the same time, however, it does indicate to users roughly where their caps are sitting at. Maybe what would be ideal would be this: open a new window that identifies how much data individuals have downloaded in the past hour, as well as the total content that they have downloaded. I don’t like the idea of ISPs modifying webpages, so what this would do is actually create a separate packet stream. The issue is that they would, as I presently understand the technology, still effectively be forcing content on the user. Maybe there could be an option to cease/modify how information was provided, including automated reports to an email account that was specified by the user…

In the case of Virgin, I think that an agnostic system just won’t work – when you have a family of 4, with people streaming on Hulu, YouTube, downloading tracks, podcasts, and movies from iTunes, etc. you are dealing with a ‘connected’ household. If you punish a household for adopting next-gen distribution techniques, you quickly transform what could be something that should be a very positive change in supply/demand chains into an economically unfeasible one. At the same time, but trying to focus on BitTorrent traffic, you’re effectively ignoring the fact that streaming video is quickly becoming responsible for the majority of transmitted packets, not to mention unfairly focusing on an application-type. While people may be using BitTorrent to infringe on content, there isn’t any reason to discriminate against people using this kind of application, any more than there should be discrimination against individuals who are more likely to use a particular brand of car to speed.