Hello guys! here's the problem I am encountering which is really bothering:

I have set up the adsl connection, I use "pon dsl-provider" to connect to internet. OK, the problem is that, after executing that command my internet does not get connected. output of plog shows:
then I do a "poff" then "pon dsl-provider" again... and again and again... after some time it finally gets connected.

To overcome this lame route, I wrote a bash script which loops and tries to connect (checks if not connected). Sometimes it takes like 15 minutes to connect at last!

Just wanted to ask you guys, is there a way to fix this? what is the reason ?

I have a solution for all the problems which are related to pppoe itself (usually crappy).
If your modem is setup as bridged+routed mode it means you can both connect directly to the ISP provider with pppoe or otherwise connect to the router only (as someone suggested before).

To connect only to the router and avoid the pppoe connection you must edit
/etc/sysctl.conf which must contain the following values (uncomment values or add where needed)

Code:

net.ipv4.tcp_syncookies = 1
net.ipv4.tcp_window_scaling = 0
net.ipv4.tcp_ecn= 0

This will avoid all problems you described.
hope it helps