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)