Announcing a /19 from a /16

Mon Jul 5 21:49:09 UTC 2004

> -----Message d'origine-----
> De : owner-nanog at merit.edu [mailto:owner-nanog at merit.edu] De 
> la part de Eric Pylko
> Envoyé : lundi 5 juillet 2004 22:02
> À : nanog at merit.edu
> Objet : Announcing a /19 from a /16
> 
> 
> Hi-
> 
> I'm working on a project within a large corporation and asked 
> their network folks about getting a /19 from one of their 
> /16s.  I wanted it to avoid NAT and any possible overlapping 
> from using RFC1918 addresses.  This project gets connected to 
> the internet at different times throughout the year at 
> different locations through different ISPs.  I would announce 
> the /19 for a short period of time, maybe a month or so.
> 
> The response I got back was that this was impossible since 
> ISPs require an announcement of the /16 the /19 would come 
> from. 

Maybe one of the (fairly rare, from what I see) actors that ingress filter
(or takes into account those small few that does) by allocation? (What
prefixes are yopu talking about?)

mh

> I have done work with ISPs before (and have read the 
> NANOG list for many years) but haven't heard of such a 
> requirement nor can I find any standards that indicate the same thing.
> 
> Does anyone have requirements of a /19 announcement requires 
> the /16 to be there as well?  The company has plenty of /16s 
> that it uses internally that are not being announced on the 
> Internet at all.
> 
> Thanks-
> 
> -Eric
> 
> 
> 