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New Member

How can I check if my 877 is adsl synched ?

Hi I have bought a used 877 modem/router.

I am trying to configure it as I am a newbie. I have tried many different configuration but now I have some doubts if the modem really works. The first thing I need to know is if it can make the adsl synching... I need of some configuration or just to plug the rf11 in the router ?

a "sh dsl interface atm0" says the modem is down. The CD led is blinking.

How can I check if the adsl signal is synched ?



Everyone's tags (1)

HelloHave been be provided


Have been be provided with any details regarding your ADSL connection from you isp

PPPoA/PPPoE settings -Would you know what mode your xDSL connection is? As this will define the configuration required on your router





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New Member

Hi Paul,thank you for your

Hi Paul,

thank you for your reply.

Well, in my supermarket-modem I see



it's an 8 mega adsl

pcv 8/36,  atm qos  ubr pcr 0,

dynamic ip, encapsulation 1483 bridged ip llc,

mtu 1492,

I dont see any clue about pppoa or pppoe.


googling looking for other infos about my provider (fastweb in italy) I found those:

Modulation: G.992.1 Annex A (G.dmt)
Latency: Fast
Multiplexing: LLC-based

encapsulation: Bridged (RFC-1483/RFC-2684)
Data Channel
VPI: 8
VCI: 36

Traffic Class: UBR



Thank you again for your help..


New Member

If I type "sh dsl int"it says

If I type "sh dsl int"

it says the modem is down,

dsl mode = unknown


Line has not yet been activated

My question is: can the configuration make problems to the dsl synching ?

or the dsl synching is something that it is or it is not ??


New Member

I want add an other info. The

I want add an other info. The firmware is 12.4.15.t7 and the modem firmware version is 3.0.14.

Maybe I need to upgrade ? to what version ?


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