Beetel 450BXi problem

[visu]

i am using beetel 450bxi + adsl router modem. i have already configured the modem username and password settings. but i got a problem when browser the net i got a error like 678, 679 after 10minutes only connected the net(BSNL). i checked the phone line and splitter, modem cable, and lan cable all good. i reseted modem and update firmware all done. but my problem is continues.............. :confuse: pLs me help me. friends :confuse: