RFC 1347 (rfc1347) - Page 2 of 9

TCP and UDP with Bigger Addresses (TUBA), A Simple Proposal for Internet Addressing and Routing

        RFC 1347   TUBA: A Proposal for Addressing and Routing   June 1992


        CLNP packets and vice versa, or encapsulation of IP packets
        inside CLNP packets. However, other shorter-term techniques (for
        example [3]) have been proposed which will allow the Internet to
        operate successfully for several years using the current IP
        address space. This in turn allows more time for IP-to-CLNP
        migration, which in turn allows for a much simpler migration
        technique.

        The TUBA proposal therefore makes use of a simple long-term
        migration proposal based on a gradual update of Internet Hosts
        (to run Internet applications over CLNP) and DNS servers (to
        return larger addresses). This proposal requires routers to be
        updated to support forwarding of CLNP (in addition to IP).
        However, this proposal does not require encapsulation nor
        translation of packets nor address mapping. IP addresses and NSAP
        addresses may be assigned and used independently during the
        migration period. Routing and forwarding of IP and CLNP packets
        may be done independently.

        This paper provides a draft overview of TUBA. The detailed
        operation of TUBA has been left for further study.


        2 Long-Term Goal of TUBA

        This proposal seeks to take advantage of the success of the
        Internet Suite, the greatest part of which is probably the use of
        IP itself. IP offers a ubiquitous network service, based on
        datagram (connectionless) operation, and on globally significant
        IP addresses which are structured to aid routing. Unfortunately,
        the limited 32-bit IP address is gradually becoming inadequate
        for routing and addressing in a global Internet. Scaling to the
        anticipated future size of the worldwide Internet requires much
        larger addresses allowing a multi-level hierarchical address
        assignment.

        If we had the luxury of starting over from scratch, most likely
        we would base the Internet on a new datagram internet protocol
        with much larger multi-level addresses. In principle, there are
        many choices available for a new datagram internet protocol. For
        example, the current IP could be augmented by addition of larger
        addresses, or a new protocol could be developed. However, the
        development, standardization, implementation, testing, debugging
        and deployment  of a new protocol (as well as associated routing
        and host-to-router protocols) would take a very large amount of
        time and energy, and is not guaranteed to lead to success. In
        addition, there is already such a protocol available. In
        particular, the ConnectionLess Network Protocol (CLNP [1]) is
        very similar to IP, and offers the required datagram service and
        address flexibility. CLNP is currently being deployed in the
        Internet backbones and regionals, and is available in vendor
        products. This proposal does not actually require use of CLNP
        (the main content of this proposal is a graceful migration path
        from the current IP to a new IP offering a larger address space),


        Callon