Upload and Download Caps
What exactly constitutes "too much bandwidth" is a bit subjective, but in the case of NTT-based fiber optic connections providers generally stick the cap at 30 gigabytes of uploads per day.
The restrictions generally are focused around upload caps since an unusually high upload rate tends to be the hallmark of P2P file sharing and torrenting. When your internet connection utilizes a separate provider (see our past article on how to distinguish carriers from providers), the provider is the one who decides how much bandwidth you can use. Similarly, carriers that also act as providers generally set their own maximum download limits. If you can read basic Japanese or have access to a dictionary, you can check out this great list of ISP's policies regarding upload and download restrictions.
Violation of an provider's upload/download policy can have varying repercussions. Some providers will automatically cut you as soon as you go one byte over the set limit while others will just let you off with a warning. Big providers like OCN might require you to call up the offices directly so you can tell them how profusely sorry you are and you will never ever dream of ever violating your terms of service ever again. Repeated violations will likely result in a termination of service with you being responsible for paying any applicable cancellation fees and penalties. Excessive bandwidth usage might also trigger a provider to start packet filtering (see below), severely limiting bandwidth, or cutting you off all together.
Packet Filtering and Bandwidth Restrictions
Some providers have taken a more aggressive stance towards file sharing and P2P by forbidding it all together. A few providers have taken the more drastic step of utilizing "packet filtering" which essentially looks at your data bit by bit and determines if it is being used for file sharing. If you are found out, expect your speeds to drop drastically.
Which providers actually use packet filtering isn't exactly clear but the big cable franchise J-Com has been known to aggressively monitor and restrict bandwidth. Providers also may monitor ports (the open connections used to connect devices over a network) depending on how strict their policies are.
Japanese copyright law is extremely inflexible. While enforcement is not as stringent as North America, getting an imposing legal document in the mail after downloading the latest Harry Potter flick is not unheard of. Illegally sharing copyrighted works can open the door to fines, litigation, and, according to the letter of the law, you can even face a penal sentence.
Getting nailed for copyright infringement (chosakuken shingai 著作権侵害) depends on the sort of deals copyright holders have with your internet provider, whether or not anyone is actually watching for illegal activity, and what the copyright status of the work is in Japan. General common sense dictates the popular works like blockbuster movies and best selling music may be monitored so use caution.
Generally speaking, if you are nabbed for infringement, your provider will send you a letter from the angry party in question telling you to knock it off and delete all copyrighted works. You may need to sign a form promising not to do it ever again. Publishers may also be able to get your address directly from an ISP to send you a similar notice. In common law parlance, this is known as a "cease-and-desist order" (keikokujo 警告状). You might even get a court summons (shokanjo 召喚状) but that would have to involve some serious malfeasance on your part.
You could not torrent at all, but if you must:
Know your terms of service. If you are not familiar with your provider's terms of service, err on the side of caution and avoid leaving torrents running all day and night and try to only do one or two at a time. Most torrenting software allows you to control the number of peers you have as well as setting customizable bandwidth limits. Also, try to find private trackers rather than open ones that are often times monitored.
Also, if you are internet savvy enough, set your port ranges to something very high since high range ports are less heavily monitored. Finally, try preferring encrypted peers when file transferring as that cuts down on the ability of providers to filter data packets.
And for our final entry we will look at signing in to your net connection and setting up wireless routers. Stay tuned!
Other Posts in this Series#2 Carriers and Providers
#3 Shopping for Service
#4 Signing up
#6 Optional Services