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Apparent paradox: Routing table shows my PC as default gateway

Last response: in Networking
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October 27, 2012 5:06:40 PM

Below are the essential rows extracted from my laptop's routing table when connected to Internet:


NetworkDestination Netmask Gateway Interface Metric
-------------------------------------------------------------------------------------------------------------------------------------
0.0.0.0 0.0.0.0 XXX.XXX.XXX.XXX XXX.XXX.XXX.XXX 1
YYY.255.255.255 255.255.255.255 XXX.XXX.XXX.XXX XXX.XXX.XXX.XXX 50
224.0.0.0 240.0.0.0 XXX.XXX.XXX.XXX XXX.XXX.XXX.XXX 1
255.255.255.255 255.255.255.255 XXX.XXX.XXX.XXX XXX.XXX.XXX.XXX 1

Default Gateway: XXX.XXX.XXX.XXX

Here, XXX.XXX.XXX.XXX is my public IP and YYY is the first octet of my public IP.

As you can see that the default gateway is set my laptop's IP itself, i.e., what I understand is, if none of the route matches, send the packet via XXX.XXX.XXX.XXX as next hop, which is again my laptop. But, what will happen to the packet then? To what IP, will the next hop be? Suppose, I am sending a packet to hit google.com which is forwarded from my laptop acting as a gateway. But, then?
October 27, 2012 6:00:21 PM

I am pretty sure that is normal for a pppoe type of connection. All it means is that it will send all the traffic out the interface no matter what the ip on the far end is.
October 28, 2012 12:42:38 AM

john-b691 said:
I am pretty sure that is normal for a pppoe type of connection. All it means is that it will send all the traffic out the interface no matter what the ip on the far end is.


But my basic networking knowledge can't find the answer to the question where the next hop of the packet is. A gateway/router must define that, isn't it? No matter whether it is normal or not, I am trying to clarify it to myself.
!