STEPS

FIRST WE HAVE TO CONFIGURE MODEM IN PPPOE MODE AS USUAL  . THEN WE HAVE TO DO ONLY TWO SETTINGS  AS DESCRIBED BELOW 

1)      GO TO INTERFACE SETUP >INTERNET 

2)      IN TCP MSS OPTION       PUT   1360    (WHICH WAS 0 EARLIER)

3)      IN TCP MTU IPTION        PUT   1492    (WHICH WAS 1500 EARLIER)

4)      CLICK ON SAVE   BUTTON

5)      GO TO MAINTENANCE > SYSTEM RESTART> SELECT CURRENT SETTING > CLICK ON RESTART

6)      MODEM WILL RESTART , WAIT TILL ADSL LED IS UP

SNAP SHOT

WE CAN ALSO DO THESE SETTING WHILE CONFIGURING MODEMS