The road side data exchange net includes {TAIL ~ a plurality} of {HEAD ~ road side data exchange devices} set on neighboring roads separately 
The road side data exchange net includes { TAIL ~ a plurality } of { HEAD ~ road side data exchange devices } set on neighboring roads separately
OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH