4G LTE Data
A ‘Japan SIM card’ will provide you with 4G LTE cellular data access whenever possible for the full service duration.
As with any other service of this type, however, please note that connection speeds may be lower during peak times or in areas where the network coverage is poor.
If a large amount of data is used, the network may also restrict your connection speed (due to their Fair Usage Policy) for a short period but basic internet access should still be available during these times.
Fair Usage Policy
If the network receives reports of a high level of usage within a short time frame (usually in excess of 3GB of usage per day), the network may apply their fair usage policy and restrict your connection speed for 24 – 48 hours.
This restriction would only usually be applied for the following day but if 500MB of data or more is used during this day (while the connection speed is restricted), this restriction may be applied the next day as well.
Once the restriction has been applied, basic internet access would usually still be available (for services such as loading simple web pages, sending an email etc) but results may vary.
Removing Restrictions
If over 500MB of data is used while the connection speeds are reduced, the network may continue to apply this restriction.
We would therefore recommend that you disable data for 1 full day (or ensure that you use no more than 500MB of data for one full day) and we would then expect the restriction to be removed the following day.