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I'm using 3G-modem to provide an Internet connection to my Linux box.

So, when I issue ifconfig command, I see the following:

ppp0: flags=4305<UP,POINTOPOINT,RUNNING,NOARP,MULTICAST>  mtu 1500
        inet 10.223.229.136  netmask 255.255.255.255  destination 10.64.64.64
        ppp  txqueuelen 3  (Point-to-Point Protocol)
        RX packets 120  bytes 33390 (32.6 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 197  bytes 23842 (23.2 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

So, the question is - what's wrong with destination, e.g. with default gateway? According to my understanding of PPP protocol, the netmask is 255.255.255.255, so the IP address of gateway should be 10.223.229.137 or something like that.

What do I miss? Or we are both on the same network, because the address is class A?

Update: route -n gives me the following:

[root@server ~]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         0.0.0.0         0.0.0.0         U     0      0        0 ppp0
10.64.64.64     0.0.0.0         255.255.255.255 UH    0      0        0 ppp0
192.168.0.0     0.0.0.0         255.255.255.0   U     0      0        0 eth0
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migrated from serverfault.com Jul 26 '13 at 10:28

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1 Answer 1

up vote 1 down vote accepted

The destination isn't the default gateway. PPP stands for 'point-to-point protocol' and this is exactly what you're seeing: the near-end point is 10.223.229.136, and the far end is 10.64.64.64.

Check your routing table (route -n): this will display the default gateway.

The 'all 1s' netmask means that there is in effect no subnet associated with the local address. Don't bother with classes of subnet: they haven't had any real-world meaning for many years.

share|improve this answer
    
I've updated the question, so route -n gives me the default gateway of 10.64.64.64. –  maniaque Jul 26 '13 at 15:57
    
So yes, your traffic is routed to the other side of the point-to-point connection. All looks healthy to me. –  Flup Jul 27 '13 at 17:11

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