hey Didou!
yes, modem provides my computer an IP everytime i boot.
and here are the results for those commands you suggested:
[broli@10 ~]$ dmesg|grep eth
divert: not allocating divert_blk for non-ethernet device lo
divert: allocating divert_blk for eth0
eth0: RealTek RTL8139 at 0xc000, 00:50:fc:e1:50:37, IRQ 11
eth0: Identified 8139 chip type 'RTL-8100B/8139D'
divert: not allocating divert_blk for non-ethernet device sit0
eth0: link up, 10Mbps, half-duplex, lpa 0x0000
divert: not allocating divert_blk for non-ethernet device ppp0
eth0: no IPv6 routers present
divert: no divert_blk to free, ppp0 not ethernet
divert: not allocating divert_blk for non-ethernet device ppp0
divert: no divert_blk to free, ppp0 not ethernet
divert: not allocating divert_blk for non-ethernet device ppp0
divert: no divert_blk to free, ppp0 not ethernet
divert: not allocating divert_blk for non-ethernet device ppp0
divert: no divert_blk to free, ppp0 not ethernet
[broli@10 ~]$ /sbin/ifconfig
eth0 Link encap:Ethernet HWaddr 00:50:FC:E1:50:37
inet addr:10.0.0.1 Bcast:10.255.255.255 Mask:255.0.0.0
inet6 addr: fe80::250:fcff:fee1:5037/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:651 errors:0 dropped:0 overruns:0 frame:0
TX packets:182 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:39060 (38.1 KiB) TX bytes:15054 (14.7 KiB)
Interrupt:11 Base address:0xc000
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:3401 errors:0 dropped:0 overruns:0 frame:0
TX packets:3401 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:4365090 (4.1 MiB) TX bytes:4365090 (4.1 MiB)