(OT?) Anyone wanna address my ISP's issues? [CIDR/BGP question]

[Elliot Finley]

On Thu, 14 Jun 2007 14:07:07 -0500, you wrote:

>[OT Warning]  Not related to FBSD, other than the use of
>ping(8), which is working as expected, apart from the fact
>that the network *isn't*.
>
>If anyone cares to give an opinion, TIA!
>
>I'm trying to get a land-based (DSL) solution to my
>rather remote office.  Found a provider, they (supposedly)
>made arrangements with the local telco, sent me the DSL
>modem, etc.  I set it up as instructed, but we're not
>getting TCP/IP here on it.  Hours and hours of frustrating
>hold music on the telephone, WWW-chat sessions that get
>nowhere, etc.  The modem "sync" is fine, but, as one tech
>put it, "sync but no surf".  It's been this way for >
>2 weeks.
>
>The DSL modem's outside (static) IP is n.n.n.70, the gw
>is n.n.n.69, and the mask is 255.255.255.252.  From
>inside, I can ping .70, but not .69 (and, needless to say,
>nothing else, either).  From the outside, it's the
>other way 'round.  Traceroute (from outside) shows different
>endpoints for the two addresses (that is, the last hop 
>before .69 is one router, and, when looking for .70, it's
>another router (but not the one that leads to .69)).
>
>If I did my CIDR homework correctly, the net is n.n.n.68/30.
>Using "BGPlay" (http://bgplay.routeviews.org/bgplay/), I get
>the message: "The selected data sources have no information on
>prefix n.n.n.68/30.  Please check that this prefix is globally
>announced."
>
>My question: shouldn't it be 'announced', if the ISP intends
>to route me TCP/IP traffic?  I apologize for my ignorance, 
>but BGP isn't something I figured to need to know at this 
>point in my life (although, it doesn't hurt to learn, usually)....

anything smaller than a /24 will be filtered.  The ISP would announce
the larger block that your /30 lives in.