Re: SPF [ Was: Re: Anti-recommendation: Comcast.]

["Matt Shields-5" <user=70@nabble.blu.org>]

 On Jan 24, 2008 8:33 AM, Matthew Gillen <[hidden email]> wrote: 
> Bill Ricker wrote: 
> >> SPF record. There is a special syntax for saying basically "any server in 
> >> domainX's SPF record can also send mail 'from' my domain". 
> > 
> > Doesn't that mean any OTHER comcast customer can forge for your domain? 
> 
> In theory, no, because they wouldn't be in Comcast.net's SPF record. 
> However, looking at their actual SPF record, it looks excessively broad: 
> v=spf1 ip4:76.96.28.0/23 ip4:76.96.30.0/24 ip4:76.96.60.0/23 
> ip4:76.96.62.0/24 ?all 
> 
> Now, that might actually not be as bad as looks on first blush, since I 
> think those IP ranges are not ones that they give to customers (my current 
> address from them is 24.34.56.xxx). 
> 
> Even if Comcast's record is overly broad, SPF will still serve it's purpose. 
> SPF is meant merely as a hint (even though some providers will tag spam 
> based on SPF alone), so it's better to be overly broad than too narrow (and 
> thereby getting mail you sent needlessly tagged as spam). 
> 
> Matt 
>