Routing over Large Clouds (rolc)
































Charter































Status: Concluded May, 1996 































































































Chair(s):































































 Andy Malis 































































Description of Working Group:































NOTE: This WG combined with IPATM to form the ION WG.































































Summary: This group is created to analyse and propose solutions to































those problems that arise when trying to perform IP routing over large































``shared media'' networks. Examples of these networks include SMDS, 































Frame































Relay, X.25, and ATM.































































Definition:































   Internetwork Layer: To avoid confusion with multiple meanings of































   ``network'' layer, we will use the term ``Internetwork'' layer to































   unambiguously refer to that layer at which IP runs. This is the































   layer at which IP routing functions. This is also the layer at which































   CLNP, DECnet, etc. run.































































Large cloud:  A collection of ``end-points'' be they routers or hosts,































   connected over a fabric such that communication can be established,































   in the absence of policy restrictions, between any two such































   entities. This communication within a cloud takes place using































































   addressing and capabilities below the ``Internetwork'' layer.































































The connectivity may or may not require circuit setup before































communication. Such a collection is considered large if it is































infeasible for all routing entities on such a ``cloud'' to maintain































``adjacencies'' with all others. Examples include, but are not limited































to, ATM, Frame Relay, SMDS, and X.25 public services.































































The group will investigate the operation of IP routing protocols and































services over ``Large Clouds.'' Whenever possible, solutions shall be































applicable to a range of ``cloud'' services. That is, the goal is a































single solution applicable to multiple kinds of large ``clouds'' be they































public or private, and independent of the specific technology used to































realize the ``cloud'' (even a very large bridged Ethernet). It is also 































an































objective that solutions, where possible, apply to network layer































protocols other than IP.































































The problems the group will cover are:































































A) The architectural implications of allowing direct communication































   between entities which do not share a common IP network number. The































   group will also entertain proposals on the use of a common IP network































   number. If (as many believe) it is infeasible, an effort to document































   the difficulties will be made.































































B) The routing/information protocol required to allow direct































   communication between two entities which were not directly































   exchanging routing information.  This will include address































   resolution.  The solution must couple closely to routing. It must































   take into account realistic connectivity policies.































































C) Operation of existing protocols between peers on such clouds. Are































   any changes necessary or desirable?  If changes are required, they 































will































   be proposed to the relevant working group.































































D) Consideration of how policy restrictions and constraints (such as































   access control and policy-based routing paths) affect A, B, and C.































































The group will also review the applicability of the work to ISDN and































POTS. These technologies have a prima-facia difference, in that the































number of simultaneous connections is much smaller. The implications of































this for routing and relaying at the Internetwork layer will need to be































explored further.































Request for Comments:

  • RFC1735 NBMA Address Resolution Protocol (NARP) (Experimental)
  • RFC1937 "Local/Remote" Forwarding Decision in Switched Data Link Subnetworks (Informational)