The MRC protocol aims to improve network routing reliability and reduce packet loss during link and node failures. It does so by pre-computing and storing backup routing configurations at each node to allow for fast rerouting onto alternate shortest paths after any failure without needing to determine the root cause. The MRC approach is evaluated to show it can reduce network traffic loads and recovery times compared to standard protocols like IGP and BGP that require more time to detect failures and recalculate routes.

1. International Journal JOURNAL OF COMPUTER ENGINEERING & TECHNOLOGY
INTERNATIONAL of Computer Engineering and Technology (IJCET), ISSN 0976 –
(IJCET)
6367(Print), ISSN 0976 – 6375(Online) Volume 3, Issue 3, October-December (2012), © IAEME
ISSN 0976 – 6367(Print)
ISSN 0976 – 6375(Online)
Volume 3, Issue 3, October - December (2012), pp. 23-29 IJCET
© IAEME: www.iaeme.com/ijcet.asp
Journal Impact Factor (2012): 3.9580 (Calculated by GISI)
www.jifactor.com
©IAEME
MULTIPLE ROUTING CONFIGURATION
A.S.Tamboli (Asst. Professor) Ms. B.A.Jadhawar(Asst. Professor)
Dept. of Information Technology Dept. of Information Technology
Annasaheb Dange College of Engineering and Annasaheb Dange College of Engineering
Technology,Ashta and Technology,Ashta
shikalgar.arifa@gmail.com bajdhawar123@gmail.com
ABSTRACT
As we know today’s world surrounded with internet and internet is the most important
part of the communication, but some routing protocols are work slow for recover link or
node. So we introduce new routing protocol called as “Multiple Routing Configuration”
(MRC). MRC protocol gives the guarantees for recovering both failed nodes and failed links,
works without knowing the root cause of failure of node or links. MRC is connectionless and
forward packet Hop-by-Hop. MRC keeps information of routing, and allow to forward packet
through shortest alternate link after the failure. Using MRC we also can reduce the traffic on
network and also reduce the time of forwarding packet after failure.
Keywords: Routing, multiple routing, shortest Path
I. INTRODUCTION
Today’s Internet is so fast, central and it covers large area every day. The main problem of
the internet to fast recover from the failure. There are many protocols to forward packet after
the failure of links and nodes but they work after the failure such as BGP and IGP. In this
case, packet can drop during the failure. The both protocols can give a more time to detect the
failure, to send the NACK message to source and calculate the shortest path for the specific
Destination. IGP is a slow process, it is reactive and global because it reacts after the failure
arises and it can involves all the nodes in the network. In case of MRC is a proactive and
local because it can stores the additional information of routing in the nodes and send the
packet hop-by-hop from previous node of failure node by shortest path. These shortest paths
are already calculated so the time for calculating shortest path is minimised after the failure,
means the time for recover the node is reduced. MRC working without knowing the root
cause of the failure such as node failure or link failure.
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2. International Journal of Computer Engineering and Technology (IJCET), ISSN 0976 –
6367(Print), ISSN 0976 – 6375(Online) Volume 3, Issue 3, October-December (2012), © IAEME
II. MRC OVERVIEW
MRC builds a set of backup routing configurations that are used to route the packet on
alternate path after failure. The backup configuration is different from original network
configuration. In observation, If traffic on a link is high then traffic doesn’t routed through
that link or node.
MRC scheme is based on three steps. First, create a set of backup configurations for
each and every node; forward the packet using one of this after the failure of node or link.
Second, for calculating shortest path use the OSPF for each backup configuration and create
forward table for each configuration. Finally, design a packet forwarding process that shows
the advantage of backup configurations to facilities fast recovery from a component failure.
III. CREATE BACKUP CONFIGURATIONS
MRC configuration is based on network topology; network topology is like a graph,
with collection of nodes and unidirectional links. It gives the guarantee fault tolerance; the
network topology graph must be bi-connected. Each link having the weight, this weight
necessary for deciding the node is isolated, restricted or normal. Isolated node doesn’t carry
any traffic; restricted links carry traffic at sufficient high weight. Isolated nodes are those
nodes that having only restricted or isolated nodes. Means restricted links are always between
the isolated node and non-isolated node. Isolated links between isolated node and non
isolated node or between two isolated nodes.
Backbone:- All isolated nodes are directly connected to the backbone configuration.
Validating configurations are connected to the backbone.
Isolated Node
Fig 1:- Isolated Node and Link
Isolated nodes are those how’s weight having infinity or maximum than the link cost.
This link cannot be used to forward the packet from one node to another node.
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3. International Journal of Computer Engineering and Technology (IJCET), ISSN 0976 –
6367(Print), ISSN 0976 – 6375(Online) Volume 3, Issue 3, October-December (2012), © IAEME
Non-isolated nodes or links either normal or restricted (nodes/links). This node and
links can be used to forward the packet from one node to another node.
Restricted Node
Fig 2:- Restricted Node and Link
Restricted nodes are those how’s weight having less than maximum cost of link but
close to the maximum cost of the link. After sending some packets at the same time through
this node, this node goes under the isolated node.
That means restricted links are used to isolate the node after forwarding some traffic.
Within MRC, Restricted and isolated links are always attached to isolated nodes.
This means that a restricted link always connects an isolated node to a non-isolated
node. An isolated link either connects an isolated node to a non-isolated node, or it connects
two isolated nodes.
IV. FORWARDING PROCESS
When the packet travel through network and reach at the point of failure, the previous
node to failure node or link is called detecting node. This node is responsible for searching
the appropriate backup configuration for that failure node or isolated node without knowing
the root cause of the failure of component. Using that backup configuration the packet can be
sent through the alternative path. This alternative path is a loop less and shortest one.
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4. International Journal of Computer Engineering and Technology (IJCET), ISSN 0976 –
6367(Print), ISSN 0976 – 6375(Online) Volume 3, Issue 3, October-December (2012), © IAEME
Fig 3:- Forward Packet Form ‘A’ To ‘B’
As shown in above figure the packet is forwarded form source ‘a’ to destination ‘b’.
There is no any failure between the source and destination the packet is sent normally but
failure in path then the backup configuration is applied if the link or node is fail then packet is
dropped and previous node can look for the alternate path in the backup configuration. There
is no alternate path then packet is dropped otherwise packet sent by alternate shortest path.
Forwarding Table
Fig 4:- Forwarding Table
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5. International Journal of Computer Engineering and Technology (IJCET), ISSN 0976 –
6367(Print), ISSN 0976 – 6375(Online) Volume 3, Issue 3, October-December (2012), © IAEME
Forwarding table shows the information about all nodes and represent the cost on
those links that are connected to the nodes.
Shortest Path
Fig 5:- Shortest Path
In this part, shows the all path present between from node and to node but use only
those path that having minimum traffic. That means having the low costs on their links.
Shortest path assures that the successful packet reach at the destination than the other path
because of the other links having the more weight than shortest path. Having more weight is
responsible for the congestion; due to congestion packets are dropped.
Forward Packet
Fig 6:- Forwarding Packet
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6. International Journal of Computer Engineering and Technology (IJCET), ISSN 0976 –
6367(Print), ISSN 0976 – 6375(Online) Volume 3, Issue 3, October-December (2012), © IAEME
This is the actual packet forwarding process. In this the packet is forwarded from
source to destination using the shortest path. In case of failure of node or link MRC use the
backup configuration and sends the packet using the alternate shortest path.
V. PERFORMANCE EVALUATION
Multiple Routing Configuration requires the routers to store the additional
information of the routing configurations and backup configurations. The amount of memory
required in the routers to store the configurations is depends on the total configuration. The
total load of the network is reduced and time required for again sending the packet from
source to destination after failure is also reduced.
Fig 7:- Graph in case node failure in IGP & MRC
The IGP and BGP are taking a several time for determining the cause of failure, and
calculating the alternate shortest path for forwarding packet from source to destination. MRC
already provides the backup configuration means on the creation of the network that’s why
the time for calculating shortest path is totally minimised. MRC is local; means time required
for forwarding the packet from detecting node to destination is less. MRC recovers the failure
components within the seconds.
VI. CONCLUSION
In this paper Multiple Routing Configurations is achieve fast recovery in IP networks.
MRC uses routing information stored on the routers and allow them to forward the packet
through routers, avoiding the failed components in the networks. In a bi-connected network
MRC gives the guarantees to recover single failed link or node. MRC works without knowing
the root cause of the failure of the components and forward the packet hop-by-hop
successfully by solving the problems. It reduces the load of the network and time required to
reach at the destination after the failure of the component.
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