From what I've read, - is a private address space. So I ran a tracert over the internet and I saw an address How is that possible? Thanks in advance!

Tracert Log:

1 1ms None    
2   ----    Timeout n/a 
3    13ms    None    
4      16ms    None    
5    11ms    ip65-46-186-97.z186 
6   24ms    vb1730.rar3.chicago 
7   ----    Timeout n/a 
8    48ms    None    
9    51ms    ae-1-0.cr0.chi30.tb 
10    62ms    None    
11      58ms    be1.clmkohpe02r.mid
  • Please share the details of your tracert, you can anonymize where necessary. – MikeDawg Feb 4 '14 at 22:35
  • It's in CSV format.[code]1,,1ms,None,---- 2,----,Timeout,n/a,---- 3,,13ms,None,---- 4,,16ms,None,---- 5,,11ms,ip65-46-186-97.z186,---- 6,,24ms,vb1730.rar3.chicago,---- 7,----,Timeout,n/a,---- 8,,48ms,None,---- 9,,51ms,ae-1-0.cr0.chi30.tb,---- 10,,62ms,None,---- 11,,58ms,be1.clmkohpe02r.mid,----[/code] ... Sorry, can't get this to display right... (I'm a new user) – pkSML Feb 4 '14 at 22:37

Not every ip address on your tracert has to be a public IP.

It might be a router or server on one of the internal nodes of an ISP that you went through on the way to your destination.

  • Just beat me to it! Good, simple and quick answer :) +1 – xstnc Feb 4 '14 at 22:40

Your ISP is likely using Carrier Grade NAT.

You can verify this by looking in your home router and checking what the WAN IP address is that you get from your ISP. You've likely been assigned an IP in the range as well. If that is the case then those suspicious hops are just the routers that are used to get from your machine to the edge of your ISPs network.

  • The hops can still be the routers even if it is not the case that the external IP address of the customer-premises equipment is in a non-publicly-routable range. – JdeBP Feb 5 '14 at 10:51
  • My public IP address is a routable address. But your link gives me something more to learn ;) – pkSML Feb 5 '14 at 12:14

If you refer to RFC1918 http://www.faqs.org/rfcs/rfc1918.html it states:

3. Private Address Space

   The Internet Assigned Numbers Authority (IANA) has reserved the
   following three blocks of the IP address space for private internets:        -  (10/8 prefix)      -  (172.16/12 prefix)     - (192.168/16 prefix) is a private IP address.

  • ... which the questioner said in the question. The actual question, which you've not answered at all, was how. – JdeBP Feb 5 '14 at 10:43

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