By setting the Next Hop field correctly (to XR2 for N3/N4/N5, to XR3 for N6/N7), only XR1 need exchange RIP-2 routes with IR1/IR2/IR3 for routing to occur without additional hops through XR1. G., "Data Networks", Prentice-Hall, Englewood Cliffs, N.  Braden, R., and Postel, J., "Requirements for Internet Gateways", STD 4, RFC 1009, June 1987. This document and the information contained herein is provided on an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. a regional network, of which the campus is a member) and are using some other routing protocol (e.g. XR1, XR2, and XR3 exchange routing information among themselves such that they know that the best routes to networks N1 and N2 are via XR1, to N3, N4, and N5 are via XR2, and to N6 and N7 are via XR3. The limited permissions granted above are perpetual and will not be revoked by the Internet Society or its successors or assigns.There are two primary ways of configuring routing: statically and dynamically.is typically used on very small networks, where the number of routes to be configured is just as small.The designers believe that the basic protocol design is inappropriate for larger networks. Contains a value from 1 to 15 which specifies the current metric for the destination.Note that this statement of the limit assumes that a cost of 1 is used for each network. If the system administrator chooses to use larger costs, the upper bound of 15 can easily become a problem. For RIPv2, this is the IP where packets for this entry should be forwarded to. A value of 16 indicates that the destination is not reachable. A circuit manager provides an interface between the connectionless and connection oriented network layers. This sets an upper limit on the sizes of routing and service advertising databases which can be propagated. Acknowledgements I would like to thank the IETF RIP Working Group for their help in improving the RIP-2 protocol. Much of the text for the background discussions about distance vector protocols and some of the descriptions of the operation of RIP were taken from "Routing Information Protocol" by C. Some of the final editing on the document was done by Scott Bradner.
It has been enhanced with various techniques, including Split Horizon and Poison Reverse in order to enable it to perform better in somewhat complicated networks.
The protocol depends upon "counting to infinity" to resolve certain unusual situations. For RIPv2, this is the subnet mask that can be applied to the IPv4 address to resolve the network portion of the address. The circuit manager takes datagrams from the connectionless network layer protocols and as necessary opens a virtual circuit to the next hop router.
If the system of networks has several hundred networks, and a routing loop was formed involving all of them, the resolution of the loop would require either much time (if the frequency of routing updates were limited) or bandwidth (if updates were sent whenever changes were detected). If the field is cleared to 0, no subnet mask is specified.
Status of this Memo This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements.
Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Copyright Notice Copyright (C) The Internet Society (1998). Abstract This document specifies an extension of the Routing Information Protocol (RIP), as defined in , to expand the amount of useful information carried in RIP messages and to add a measure of security.
We'll start with RIP fundamentals and then discuss how to configure this protocol.