Routing Policy and

For the first time we have had to deal with Sprint's routing policy as
defined by Here is the situation.

One of our dialup customers wants to access his website in the network at another provider. PSI is advertising it as a
/24. According to Sprint's routing policy, they do not honour anything
longer than a /19 in .

It's interesting that PSI routes it at all. While IP ownership (note the
NON-PORTABLE below) and routing aren't necessarily interconnected, I
suggest contacting the block's owner and seeing if they know it's
alternately routed. If they wish, they can request that PSI un-route this
block. However, that would break whomever is using it. The user should
re-number into PSI space, and this issue will go away. If the user is
multi-homed, they should investigate the adivisibility of getting a CIDR
block which they can announce as an aggregate.

My $0.02


PSI bought iSTAR earlier this year, so it's not really surprising that
they're routing these networks.


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Anyways to address the actual question:

I haven't dealt with anyone other than Sprint filtering space longer than
/19 in the but in the past I had issues with both UUnet and
Agis filtering errant /24's and /23's out of

I've been very clearly telling all my customers that while I will route
their IP space for them, as long as its allocated to them - I will not be
responsible for anything that we know Sprint may or may not filter on any
given day. It generally works well, they take space from me and we
resubmit their space to whomever the governing body is/was at the time.

For customers that really have a need we push as hard as we can to get
them their own /19 so they'll not have to renumber but we know the issues
involved with this.