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ugh1
26-11-2003, 07:22 PM
I noticed this weird setup on my pc:

Windows 2000 IP Configuration

Host Name . . . . . . . . . . . . : ugh
Primary DNS Suffix . . . . . . . :
Node Type . . . . . . . . . . . . : Broadcast
IP Routing Enabled. . . . . . . . : Yes
WINS Proxy Enabled. . . . . . . . : No
DNS Suffix Search List. . . . . . : ihug.co.nz

Ethernet adapter Local Area Connection:

Media State . . . . . . . . . . . : Cable Disconnected
Description . . . . . . . . . . . : 3Com EtherLink 10/100 PCI For Comple
te PC Management NIC (3C905C-TX)
Physical Address. . . . . . . . . : 00-50-04-B9-C1-2B

PPP adapter IHUG:

Connection-specific DNS Suffix . : ihug.co.nz
Description . . . . . . . . . . . : WAN (PPP/SLIP) Interface
Physical Address. . . . . . . . . : 00-53-45-00-00-00
DHCP Enabled. . . . . . . . . . . : No
Autoconfiguration IP Address. . . : 203.118.166.108
Subnet Mask . . . . . . . . . . . : 255.255.255.255
Default Gateway . . . . . . . . . : 203.118.166.108
DNS Servers . . . . . . . . . . . : 203.109.252.42
203.109.252.43
NetBIOS over Tcpip. . . . . . . . : Disabled

Can someone explain why the subnet mask is as it is?

Why is the default gateway the same as my IP address?

By all rights no traffic should leave my PC, yet it does!!!

-=JM=-
26-11-2003, 08:51 PM
Here is mine:

Windows IP Configuration

Host Name . . . . . . . . . . . . : My PC
Primary Dns Suffix . . . . . . . :
Node Type . . . . . . . . . . . . : Unknown
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No

PPP adapter Snap:

Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : WAN (PPP/SLIP) Interface
Physical Address. . . . . . . . . : 00-53-45-00-00-00
Dhcp Enabled. . . . . . . . . . . : No
IP Address. . . . . . . . . . . . : 202.124.110.106
Subnet Mask . . . . . . . . . . . : 255.255.255.255
Default Gateway . . . . . . . . . : 202.124.110.106
DNS Servers . . . . . . . . . . . : 202.37.101.1
202.37.101.2
NetBIOS over Tcpip. . . . . . . . : Disabled

-=JM=-
26-11-2003, 08:54 PM
All makes sense to me. That subnet is normal. If your PC doesn't use your own machine as a gateway... what is it going to use? Unless you've got a network running in which case you'd have a different IP/Subnet as well.

ugh1
26-11-2003, 09:35 PM
> All makes sense to me. That subnet is normal. If your
> PC doesn't use your own machine as a gateway... what
> is it going to use? Unless you've got a network
> running in which case you'd have a different
> IP/Subnet as well.

Is it not supposed to use the gateway provided by the ISP, after all I do not have a connection to any back bones.

So how does my PC know how to route to 143.14.1.3 for example, as I am not in the same subnet, nor do I host that subnet?

-=JM=-
26-11-2003, 10:02 PM
It will send out a packet addressed to that IP and the router at the ISP should take care of it. That's basically how it works.

linw
26-11-2003, 11:24 PM
Perhaps it might be helpful to google "PPP/SLIP". Basically, the PPP protocol causes the dial-up and establishes you as a serial node to the ISP's network. Thus the packet sends/receives happen via the PPP code. And as JM says, after that the ISP's router handles things.

The subnet mask of all 255's simply means that your NIC will respond to any IP no. The "subnet" is ALL IP no.s, in effect.

Cheers.