Pooled Quota (PQ) jyadatar long distance trains me paaya jaata hai. Ek route me end to end ke alawa kuch aise bhi important stations hote hai jahaan se bhaari maatra me ticket booking hoti hai. So aise kuch chuninda stations ek doosre ke saath quota share karte hai, jise PQ kaha jaata hai.
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Ek udaharan lijiye: Ek train A se E tak jaa rahi hai, with halts at B,C,D.
So...
more... A-E mostly GNWL rahega. Yeh sochiye ki B-C aur C-D important stations hain jisme hamesha demand rehti hai. So yeh 3 stations ek dusre ke saath seat ka quota share karenge. Suppose 100 seats ka quota hai, Agar B station ne 50 seats book kar li toh C station ke paas booking ke liye sirf 50 seats hi upolbdh rahegi kyunki B se already 50 seats ki booking ho chuki hai. En-route important stations ko PQWL me rakhne ka ek aur faayda yeh hai ki A station se saari booking na ho, taaki beech wale stations ke liye bhi kuch seats bache.
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PQWL mostly intermediate stations ke liye use hota hai, so isme berth sharing ya berth-multiplexing ka bhi istemaal hota hai depending on journey leg and availability.
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