![](bg2.png)
Border Gateway Protocol (BGPv4) (Rekhter &
Hares, 2006) – Extends distance-vector idea by
having multiple attributes acompanying the
single prefix update. BGPv4 is currently the
only one EGP that is being used and it is often
refered as policy-control routing protocol.
Enhanced Interior Gateway Protocol (EIGRP) is
the backward compatible successor of previous
Cisco proprietary Interior Gateway Protocol (IGRP).
It is categorized as a hybrid routing protocol which
means that it is a crossover between distance-vector
(topology is known based on announcement from
neighbors) and link-state protocols (instead of
periodic updates, topology changes are propagated
immediately). Down below follows the list of main
beneficial features of EIGRP:
EIGRP employs Diffusing Update Algorithm
(DUAL) (Garcia-Lunes-Aceves, 1993) that
effectively propagates any topology change
and minimizes path recomputational time;
Currently EIGRP is the only routing protocol
that guarantees loop-free topology even during
the time when topology is actively converging
towards a new routing state;
EIGRP leverages its own reliable transport
protocol (even for multicast data transfer);
In the contrary to other distance-vector
protocols, EIGRP is capable of sending event-
driven partial bounded updates;
It has neighbor discovery and recovery
mechanism to determine route reachibility via
particular adjacent node;
EIGRP contains protocol-dependent modules
that allow operation over different network
protocols (including IPv4 and IPv6);
The EIGRP was introduced in 1993 as a cojoint
effort of Cisco and SRI International (Albrightson,
et al., May 1994). Initial and later measurements
revealed that it outperforms other routing protocols
(i.e., speed of convergece, network bandwidth
utilization, queing delay) (Xu & Trajkovic, 2011).
Despite its beneficial aspects (or maybe because of
them) it had been protected as one of the major
Cisco intellectual properties by a bunch of patents
for nearly twenty years. In the beginning of 2013,
basic EIGRP design and functionality were
submitted as a publicly available IETF informational
draft (Savage, et al., 2013).
The project ANSA (Automated Network
Simulation and Analysis) running at the Faculty of
Information Technology is dedicated to develop the
variety of software tools that can create simulation
models based on real networks and subsequently to
allow formal analysis and verification of network
configurations. This paper outlines a new simulation
module, which is a part of the ANSA project and
which extends functionality of the INET framework
(OMNeTpp/INET, 2014) in OMNeT++ (OMNeTpp,
2014).
This paper has the following structure. The next
section covers a quick overview of existing EIGRP
implementations (either real or simulation ones).
Section 3 deals with our contribution, mainly
necessary theory, proposed design and subsequent
implementation. Section 4 presents validation
scenarios proving corectness of the implementation.
The paper is summarized in Section 5 together with
unveiling our future plans.
2 STATE OF THE ART
Currently none of vendors other than Cisco supports
EIGRP in its active network devices. Despite
positive campaign targeting wider EIGRP
acceptance, many manufacturers and customers
remain skeptical and rely on a long-time proven
open solutions like OSPF or IS-IS. The one of the
first publicly available open-source EIGRP routing
demon is being developed at the University of Žilina
(GitHub/janovic, 2013) within the scope of Quagga
project (nonGNU, 2013).
A freely available demonstration tool called
Easy-EIGRP (SourceForge, 2013) exists rather for
educational purposes.
OPNET simulator has contained EIGRP
simulation modules even before its public IETF
release. However, its functionality is limited and it
lacks IPv6 support for EIGRP. Nevertheless,
OPNET and its simulation models were used to
conduct several measurement studies comparing
different routing protocols including EIGRP (Wu,
2011).
Previously described state of EIGRP deployment
affirmed our decision to offer academic and
enterprise community with a full-fledged EIGRP
implementation with all usually employed features.
The current status of unicast routing support in
OMNeT 4.4.1 and INET 2.2 framework is according
to our best knowledge as follows. The IPv4 (named
networkLayer) and IPv6 (pragmatically called
networkLayer6) layers are already parts of INET
framework. The framework contains OSPFv2 as the
only available dynamic routing protocol.
During ANSA project development we have
extended original simple router module to be dual-
stack and enhanced it with a variety of dynamic
routing protocols (RIP, RIPng, IS-IS, OSPFv3,
EnhancedInteriorGatewayRoutingProtocolforOMNeT++
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