traceroute going through 10.x.x.x ... Why?

I'm getting some really high pings to various game servers in my own country at peak hours. Before I complain to the ISP I want to know what some of these results in my tracert are:

Tracing route to 212.187.209.182 over a maximum of 30 hops

  1    <1 ms    <1 ms    <1 ms  local.gateway [10.0.0.2]
  2    11 ms    11 ms    11 ms  adsl-77-86-58-254.karoo.kcom.com [77.86.58.254]

  3    31 ms   218 ms    12 ms  10.102.243.65
  4    10 ms    11 ms    12 ms  10.102.240.213
  5    14 ms    15 ms    14 ms  10.55.0.209
  6   186 ms   205 ms   206 ms  212.187.137.133
  7    70 ms   136 ms   196 ms  ae-11-11.car1.Manchesteruk1.Level3.net [4.69.133
.97]
  8    33 ms    32 ms    31 ms  ae-4-4.ebr1.London1.Level3.net [4.69.133.102]
  9    28 ms    28 ms    22 ms  ae-59-114.csw1.London1.Level3.net [4.69.153.126]

 10    25 ms    24 ms    24 ms  ae-1-51.edge4.London1.Level3.net [4.69.139.74]
 11    20 ms    19 ms    23 ms  195.50.122.154
 12    55 ms    77 ms    50 ms  212.187.209.182

Trace complete.

What're the 10.x.x.x in steps 3, 4, 5? It's already gone out to the exchange so why am I back in local intranet space?

Thanks

traceroute

Ben

Posted 2012-02-07T19:56:11.610

Reputation: 13

possible duplicate of private address in traceroute results

– kinokijuf – 2014-07-07T10:34:50.567

Unless your local gateway includes the entire class-A range of 10.* that's no longer intranet space. – music2myear – 2012-02-07T20:05:13.550

Answers

10.0.0.0/8 is a private network so this means your ISP is using private addressing within their own network, probably to conserve limited IPv4 space especially if they have a relatively small allocation from RIPE.

Garrett

Posted 2012-02-07T19:56:11.610

Reputation: 4 039

It just means your traffic is being forwarded through some internal nodes in another network. It's not back in your network. This is pretty normal I think (I have similar hops when I do this from home).

You won't be able to route traffic directly to these nodes, of course, but there's no reason they can't forward your traffic inside your ISP's network. Your packet catches a ride through their private network and then gets back onto the Internet proper.

FatalError

Posted 2012-02-07T19:56:11.610

Reputation: 1 913

On a related note, why does it hit the subrange 212.187.x.x at step 6 and then only get to 212.187.209.182 at 13? Why does it go through those other places? – Ben – 2012-02-07T20:16:28.713