what does that mean?
how long till i can log in again?
why am i restricted?

Follow this guide : http://forums.d2jsp.org/topic.php?t=39461179&f=21

It only works with dynamic IP adress if yours is static you have to wait it out.

It simply means that you do not have access to battle.net for a specific amount of time. Most common reasons for this are

• Rapidly connecting and disconnecting to Battle.net
• Creating or joining numerous games within a short time period

To be exact, creating more than 20 games/hour causes this problem. It mostly lasts up to 72 hours but can also be more.

Use following guides to get rid of it

Guide To Bypassing A Temp IP Ban
Realm Down & Temp Ban Reversal Guide

Keep in mind you need a dynamic IP for this to work.

More information about it here: http://us.blizzard.com/support/article.xml?locale=en_US&articleId=20794