[Mageia-discuss] home network using broadband router

Wed Mar 7 00:41:02 CET 2012

OK, you have two PCs on a private network with addresses in the range
+192.168.?.?.
+
+You reported only 192.?.?.? If that is accurate then the addresses are
+public, meaning if I knew what they are then I could reach them from
+here.
+
+Forgive me if I tell you things you already know. IP networks are
+defined by their address. My home network, for example, has been
+defined by me to occupy only addresses in the range 192.168.0.0 to
+192.168.0.255. These are only 256 of the 65536 addresses available. My
+network has no awareness of the possibility of other addresses because
+I have not configured it. My router's configuration web address is
+192.168.1.1, but that is not within my network, so even though I am
+physically connected to it, its address is inaccessible to me.
+
+Technically, my network's routing table has no information on how to
+reach 192.168.1.1 and by definition (it is private, remember) there is
+no way to reach it via the public network - it simply does not exist
+there.
+
+So, if your router and each of your PCs share the first two octets of
+the address (192 and 168) and your network mask is 255.255.0.0 then
+any address in the range 192.168.0.1 to 192.168.255.253 (or
+thereabouts) is valid for your network.
+
+Let's check your network mask so we know the extent of your private
+network. Use the ifconfig command in a console (you might need to be
+root for this) and look for the line in the output for your eth?
+interface which looks something like this;
+
+inet addr:192.168.0.111  Bcast:192.168.0.255  Mask:255.255.255.0
+
+You can see on mine that the mask is 255.255.255.0 which means that
+only the eight bits of the final octet can be used on my network for
+unique addresses - 0 to 255. So what is your network mask?
+
+On 06/03/2012, e-letter <inpost at gmail.com> wrote:
+> On 06/03/2012, mageia-discuss-request at mageia.org
+> <mageia-discuss-request at mageia.org> wrote:
+>>
+>> Message: 3
+>> Date: Tue, 6 Mar 2012 00:47:01 +0000
+>> From: WALKER RICHARD <richard.j.walker at ntlworld.com>
+>>
+>> Quick answer; yes
+>>
+>> man ifconfig should get you started. From memory you can set an
+>> address for an ethernet card with something like;
+>>
+>> ifconfig eth0 192.168.0.22
+>>
+>> That implicitly brings up the connection.
+>>
+>> This much is already working for you as you say both PCs can reach the
+>> internet. So let's take a step back. I don't want you to "publish"
+>> your PC addresses, but if they are both on the same network then they
+>> should both have addresses in the private network ranges. The most
+>> common on routers are;
+>>
+>> 10.?.?.?
+>> 192.168.?.?
+>>
+>
+> command terminal 'ifconfig' returns value for eth1, '192...', but not
+> '10...'.
+>
+>>
+>> Can you configure your router? Do you know if it has a web-based
+>> configuration address? If you haven't come across this before, this is
+>> a "web page" generated by your router which provides access to its
+>> configuration by means of forms on web pages. It is normally accessed
+>> by entering the address in your browser, but this cannot easily work
+>> if your PC and your router are on different networks, with different
+>> address ranges. For example, the router might be on 192.168.1.1 and
+>> your PC is on a.b.x.x  where a and b are NOT 192 and 168.
+>>
+>
+> yes, there is a configuration address 'http://192...' accessible via
+> web browser.
+>
+>> Let us take one more step back. When you configured your network on
+>> each computer (using MCC?)  did you opt for manual or automatic (via
+>> DHCP) configuration of the network address? That, I think, is the key
+>> starting point.
+>>
+>
+> automatic dhcp. To check, the command 'drakconnect' was used to
+> activate the network configuration process; the default is automatic
+> ip (bootp/dchp) connection protocol
+>
+>> If it is manual then you chose the addresses and typed them in. If it
+>> is automatic (via DHCP) then they will have been allocated by EITHER
+>> your router (which seems unlikely given the trouble your having) OR by
+>> your ISP, and that means they are permitting you to have more than one
+>> public address for your location AND that the address really is
+>> public; if I knew your address I could probe your network - that is
+>> potentially highly risky and is why the common practice, in these
+>> parts, is for each subscriber to get one public address and have the
+>> modem/router provide NAT for private networks on the premises.
+>>
+>
+> I think the ip address is determined by the isp; if the router is
+> switched off and then on, a new ip address is assigned.
+>
+>> I hope I haven't confused the issue. Let me re-state the important
+>> questions:
+>> 1. Are your PC addresses similar to each other?
+>
+> yes, they differ by a digit
+>
+>> 2. Are they in the private network range? (10.?.?.? or 192.168.?.?)
+>
+> yes, 192...
+>
+>> 3. Do you have the make and model of your router? (yes/no will do for
+>> now.)
+>>
+>
+> yes
+>
+