Teng, You can also use whois to determin who owns the /30 between the hop in question. If ISPx comes up as the holder of the netblock in the registration then that traceroute result is comming from ISPx. Hopefully this helps! - Robert
-----Original Message----- From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu]On Behalf Of Teng Fei Sent: Monday, June 02, 2003 9:11 PM To: nanog@merit.edu Subject: About the address allocation convention between ISPs
Hello everyone,
I have a question about the convention of address allocation between ISPs. If a smaller ISP tries to establish connection with its provider, does this small ISP configure one of the interface on its boarder router using an IP address obtained from the provider, or it is the other way around, that is, the provider uses one of the IP address belongs to the customer to configure the provider's boarder router?
I have this question because I am trying to identify the link between two organizations from traceroute measurements. How the addresses are allocated will affect the identification of the inter-domain link by exactly one hop.
I am not sure if there is such a convention at all, or the address assignment is randomly decided according to the agreement between the customer and the provider?
Since I know there are many seasoned network professionals on this mailing list, I think it might be a proper question to ask here. Would anyone kindly be willing to share your experience? Thank you very much!
Sincerely
Teng