According to the German Residence Act, valid since January 1, 2005, the residence permit is issued as one of the following:
Residence permit (Aufenthaltsgestattung)
If you apply for refugee status in Germany, you will first receive permission to reside (Aufenthaltsgestattung). This is a temporary, and not a proper residence permit. Only once your refugee application has been approved will you receive a regular residence permit (Aufenthaltserlaubnis).
Suspension of deportation (Duldung)
A suspension of deportation (Duldung) is not a proper residence permit. It is issued by the immigration office when deportation has been suspended. It means that the holder must leave Germany, but, for various reasons, he temporarily cannot leave the country or be deported. A suspension of deportation can be issued for a duration of multiple months.
If you have permission to reside (Aufenthaltsgestattung) or a suspension of deportation (Duldung) and have found employment, you must immediately apply for a work permit at the immigration office. Your application will be reviewed by the immigration office. The International Placement Services division of the government employment office (Agentur für Arbeit) makes the final decision on whether or not you are allowed to work.
Further information: http://www.bamf.de