sorry for the earlier blank message

Mon May 5 23:44:55 UTC 1997

regarding my suggestion (although terse) with regard to 
set community no-export.  my box ran out of space and
mh ate the message (delivered a blank).  i would let it
go, and continue to look stupid, but i've recieved quite 
a few messages to let me know that my message was a blank,
so to say thank you, please stop now, and to look perhaps
even more stupid... :-)

press d now or forever conceal your boredom:-),

to re-cap,  

someone described the need to use a purchased connection to sprint
(or any other provider) as a customer-traffic-only-peering.  the right
way to do that would be for the seller to engineer a community that
accomplished sending routes to their own customer networks, but not
advertising those routes to any of their non-transit peers.

given that a majority of the networks that connect to large providers
are not bgp speakers (are within the provider's own AS) and those that do
speak bgp either take a limited set of routes and have alternate connectivity
(ie. a transit provider) or take a limited set of routes and generate
default from some of those routes,

i thought that a simple work-around for the case of a provider (A)
who would like to buy bandwidth from another provider (S) rather than
burn interconnect bandwidth for traffic to and from that same provider
(S) would be to set no-export on the advertised routes to that provider
(S).  

Given that the provider (A) already had global reachability and only
wanted to get to the other provider's (S) customers through the bandwidth
purchased from that provider (S) set no-export fails for those customers of the
provider (S) who are singly-homed to provider (S) and are default-free. 
ie, if another network (X) takes full routes from the provider (S) and 
has no other connectivity and no gateway of last resort,  provider (A) is 
not visible to the original network (X).  

i didn't think of this case, i can't think of why someone would want to
be homed to only one provider and be default-free, but i'm sure that
there's a reason. 

the other part of the message was to point out the sh ip bgp nei a.b.c.d adv
command which others have already done.

Jeff Young
young at mci.net