North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: Exodus / Clue problems
>Define "network border." I used to block all traffic from or to RFC1918 [[email protected] /]# traceroute mae-east.fnsi.net traceroute to mae-east.fnsi.net (192.41.177.11), 30 hops max, 40 byte packets -----> 1 border-core0-eth1.Columbus.EnterZone.Net (209.41.244.1) 0.538 ms 0.444 ms 0.411 ms | 2 core1-eth0-ENTERZONE.Columbus.fnsi.net (209.115.127.21) 0.916 ms 0.783 ms 0.774 ms | ---> 3 border1-atm6.Vienna.fnsi.net (206.183.239.90) 23.132 ms 23.797 ms 23.829 ms | | | |-- That is the network border of my provider at mae-east. | |---- That is the network border for MY network. The DEMARC where my network ends and my providers begins. I can't tell you precisely where yours is since @home has decided to block the traceroute. [[email protected] /]# traceroute www.senie.com traceroute: Warning: Multiple interfaces found; using 209.41.244.2 @ eth0 traceroute to fennel.senie.com (204.69.207.2), 30 hops max, 40 byte packets 1 border-core0-eth1.Columbus.EnterZone.Net (209.41.244.1) 0.542 ms 0.438 ms 0.411 ms 2 core1-eth0-ENTERZONE.Columbus.fnsi.net (209.115.127.21) 0.896 ms 0.768 ms 0.731 ms 3 core1-atm0.Cleveland.fnsi.net (209.115.127.102) 12.083 ms 9.756 ms 9.316 ms 4 border1-atm6.SanJose.fnsi.net (206.183.239.94) 66.729 ms 65.678 ms 63.696 ms 5 bb2.mae-w.home.net (198.32.136.70) 67.027 ms 65.376 ms 76.126 ms 6 172.16.2.250 (172.16.2.250) 90.842 ms 78.524 ms * 7 172.16.2.58 (172.16.2.58) 146.095 ms 130.080 ms * 8 10.0.248.34 (10.0.248.34) 118.753 ms 125.679 ms 128.392 ms 9 10.252.48.218 (10.252.48.218) 156.053 ms !X * * 10 10.252.48.218 (10.252.48.218) 129.488 ms !X * 146.837 ms !X Bad idea in my book. By the way, you might want to ask them about all of those *'s. Nasty, nasty, nasty. In addition, path MTU discovery won't work on your network because of the RFC1918 addresses. Don't get me wrong. I personally use RFC1918 addresses within my network. Those are NON-EXPOSED hosts however and there is no need for path discovery to take place. In your case, your provider wanted to save 4 IP addresses, a /30. >addresses, but my present upstream is using 10.0.0.0/8 and >172.16.0.0/16, at least, for their internal use. So, the IP address of >the WAN interface on my router connecting to them has a 10.0.0.0/8 >address. If I block incoming traffic to 10.0.0.0/8, they can't monitor >my net. Find out from them SPECIFICALLY which machine they want to monitor your router from and open your router up to that IP address individually. Block the rest of them. > >It appears this is becoming the preferred way for ISPs to limit their >use of address space for internal-only functions. While this makes sense The key phrase here is "internal-only." I would hardly consider your router or any router between yours and the rest of the world to be considered "internal-only." >at some levels, attached corporate networks may have already used those >addresses. The result is some level of confusion, though for the most >part it doesn't break too many things. Mostly, it's just annoying since >firewalls can't filter out stuff they'd otherwise limit. I can find no good reason for joe blow fortune 1000 company to use anything other than RFC1918 addresses on their INTERNAL network and run NAT or set up a proxy or something. I can also not find any good reason to use RFC1918 space between routers. It breaks too many things. I want to see you poll or for that matter, log into your router from any other network than your own. I Hope nothing happens that would require your PERSONAL attention while you're at some convention, on vacation, etc. > >In cases where ISPs use RFC1918 addresses within their networks, they >really should: > >- Tell their downstream customers WHICH of these blocks are in use. > >- Provide filters at peering points that ensure RFC1918 addresses from > outside the ISP's space do not come in from outside. > >- Provide Ingress filtering at all downstream customer ports to ensure > only valid source IP addresses come from their customers. > ...and one last point... - Have someone loan them a clue about why they should NOT use RFC1918 space in the way your isp is doing so. ------- John Fraizer | __ _ The System Administrator | / / (_)__ __ ____ __ | The choice mailto:[email protected] | / /__/ / _ \/ // /\ \/ / | of a GNU http://www.EnterZone.Net/ | /____/_/_//_/\_,_/ /_/\_\ | Generation A 486 is a terrible thing to waste...
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