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Re: ISPs Blocking Private Addresses?
From: "Eric M. Carroll" <ecarroll () rogers wave ca>
Date: Sun, 8 Feb 1998 22:19:44 -0500 (Eastern Standard Time)
Peter,
Do most ISPs explicitly block private IP addresses (e.g. 10.X.X.X) at their borders? Do the "default-less" ISPs filter private addresses or do they let routing/forwarding do the work?
More clueful ISPs do in fact block private address space exchange via BGP. Many also filter. Smaller ISPs tend to miss these steps, and there is frequently someone advertising private space at the NAPs from time to time. And some believe it, surprisingly. Many cable networks, like Rogers and @Home use net 10 for numbering internal devices for SNMP survellience, like modems and switches. While INTERNIC may not mandate it, they are sensitive to 2 IP addresses per household drawn from the public space. As such, when @Home and Rogers merged networks, there was some private address space reconcilication required. Thus, you cannot assume that private address space is not routed "privately" within a given ISP's backbone. Needless to say, they are usually very vigilant about route and packet filtering. Regards, Eric Carroll eric.carroll () acm org Tekton Internet Associates
Current thread:
- ISPs Blocking Private Addresses? Peter Ford (Feb 08)
- Re: ISPs Blocking Private Addresses? Bradley Reynolds (Feb 08)
- Re: ISPs Blocking Private Addresses? Marc Slemko (Feb 08)
- Re: ISPs Blocking Private Addresses? Richard Yoo (Feb 08)
- Re: ISPs Blocking Private Addresses? Eric M. Carroll (Feb 09)
- Re: ISPs Blocking Private Addresses? Joe Shaw (Feb 09)
- Message not available
- Re: ISPs Blocking Private Addresses? Jay R. Ashworth (Feb 09)
- Message not available