I am building a lab network with about 10 virtual routers and 20 host machines (also virtualized) as a part of a school project. The aim is to demonstrate a wide range of IPv6 routing, deployment and transition mechanisms. However, there is a problem... I am only entitled to very limited network resources - max. 10 IPs with individually opened ports/protocols. For such a dual-stack netowork, I would require at least a /25 of IPv4 space to comfortably implement the network without resorting on private IP ranges and NAT (atleast in the backbone area) and also to be able to demonstrate 6to4 and similar mechanisms.
Getting the temporary IP range assignment from a local academic LIR would be posible, but it is a considerable bureaucratic burden (unlikely to be completed until April when my project is due). Running BGP is also not an option for me, so I am unable to bring my own PI space.
Since performance of the network is not very important to me, I figured, I could use tunneling to "bring" more IPs to the network. I know there are many IPv6 tunnel brokers, so getting IPv6 in is not really an issue. What I am looking for is a similar concept, only for IPv4 addresses - not individual ones, but a whole subnet.
So, does there exist an IPv4 tunnel broker where I could rent a subnet and get it routed to me through a tunnel (GRE, IPIP, OpenVPN, ...) ?