Date: 201502
Local time of day: 0001-0600
Location: ZBW.ARTCC, NH
Light: Night
Aircraft: B737 Undifferentiated or Other Model
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Descent
Airspace: Class E ZBW
ATC / advisory: Center ZBW
Reporter organization: Government
Reporter function: Enroute
Reporter qualification: Air Traffic Control Fully Certified
Human factors: Confusion; Training / Qualification; Workload; Time Pressure
Anomaly: Airspace Violation All Types; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Air Traffic Control
When detected: In-flight
Result: General None Reported / Taken
Contributing factors: Human Factors; Procedure; Airspace Structure
Primary problem: Procedure

Narrative: I was working R34 combined with R47. Metering to BOS in effect; delays of 0 - 4 minutes. BOS was landing Runway (RY) 4R; and I was using the 'Descend Via' clearance; which had been in effect for a couple of weeks; but which I had not been accustomed to using under these circumstances. Near the tail end of a string of arrivals; which had required extensive vectoring and laddering (step-descent); a B737 had flown a little too far to the east for me to feel comfortable giving him a left turn back to PROVI to rejoin the ROBUC1 STAR (about 100 degrees). I decided to send them to the next fix; JOODY; to soften the turn somewhat; and gave the same to the next aircraft; as well. (The next group of planes would be able to proceed over PROVI.)Since there is no mandatory altitude over JOODY; the B737 was able to descend to 9;000 at SOFEE; the next fix. Because the B737 was not over PROVI; he was also not flying through a delegated 'triangle' of airspace given to Boston Approach by Providence Approach when BOS is landing RY 4R. The B737 descended into PVD ATCT's airspace. I had already changed him to Boston Approach. I stopped the following aircraft at 12000 when I realized that something had not gone as I expected.Even after 33 years in the FAA; I guess my experience was not enough to overcome my lack of experience in applying the new 'Descend Via' procedure. The procedure works fine when there are no delays; and when compression is not a factor. When vectoring off-course and rejoining the STAR; the added phraseology can become cumbersome and unwieldy (especially considering its newness). I should have added 'EXCEPT maintain 110 until JOODY'.I can add here that I did not have a D-side at the time; but it would been necessary for that person to have been able to recognize my mistake and point it out to me.




Synopsis: When traffic compression required the Center Controller to vector and manually descend traffic on the ROBUC RNAV STAR to runway 4R at BOS; he cleared a B737; currently on a vector; direct to JOODY (a waypoint with no crossing restrictions) at which point the jet began a descent so as to cross the next fix; SOFFE; at or above 9;000 feet as restricted. While doing so the flight entered airspace given via LOA (Letter Of Agreement) to Providence Approach when BOS is landing on 4R. The reporter cited the 'cumbersome and unwieldy' nature of 'descend via' clearances when addressing returns to the STAR after interruptions.