Street Porting is the reshaping and/or enlargement of the stock intake ports within the boundaries of the corner and oil seal tracks to increase the amount of air that is drawn into the engine over a particular RPM range.
As increasing the airflow in one area of the RPM range will harm airflow in another band, care must be taken to under the performance goals prior to porting. If your engine is already ported, did your engine builder ask you what YOU wanted from the engine BEFORE porting or are they just using predefined 'templates' from the likes of Racing Beat and others?