> On Oct 10, 2016, at 14:59 , Baldur Norddahl <baldur.nordd...@gmail.com> wrote: > > > > Den 10/10/2016 kl. 22.27 skrev Owen DeLong: >> Not true… There are myriad reasons that the /24 might not reach a network >> peered with ISP-A, including the possibility of being a downstream customer >> of a network peered with or buying transit from ISP-A. In the latter case, >> not an issue, since it’s paid transit, but in the former (peered, not >> transit), again, ISP-A is probably not super excited to carry traffic that >> someone isn’t paying them to carry. >> > > But ISP-A is in fact being paid to carry the traffic. Supposedly ISP-B has a > paid transit relation to ISP-A. In the case the transit link is down ISP-A > might have to transport the traffic through a less profitable link however.
Which isn’t really in the agreement between ISP-B and ISP-A unless it was specifically (and unusually) negotiated. Also, you’re assuming that the leased space came with a transit agreement. In many cases, address leases don’t, so consider the additional scenario where ISP-B leases addresses from ISP-A, but has transit contracts with ISP-C and ISP-D but no connection at all to ISP-A. > I know that if ISP-A was my network I would be making money even with the > transit link down. Yes I might have to transport something out of my network > through one of my transits, but outbound traffic is in fact free for us > because we are heavy inbound loaded. Yes, but it doesn’t help if it also came in on a transit link. Any traffic you both receive and transmit on transit costs you money pretty much no matter who you are. Owen
