WE CAN NOT INCREASE THE CAPACITY
BEYOND CERTAIN LIMIT. FOR EX OCB283 R25 IS HAVING LIMIT OF 8 LAC BHCA. IN A BIG CITY IF WE INSTALL ONE TANDEM EXCH EVEN IF THERE ARE 50 LOCAL EXCHANGES CONNECTED TO IT, IT WILL HANDLE OVFL TRAFFIC PLUS IT WILL BE THE ALTERNATE PATH FOR DIRECT CONNECTIVITY BETWEEN TWO LOCAL EXCHANGES. SO IT IS VERY USEFUL. HERE SUB ARE NOT DIRECTLY CONNECTED.