# PrECast: An Efficient Crypto-Free Solution for Broadcast-Based Attacks in IPv4 Networks
## 1 Introduction  
In this paper, we focus our attention on the broadcasting feature in the Internet Protocol (IP) Version 4 (IPv4). Several important IP-based services like the Bootstrap Protocol (BOOTP) and the Dynamic Host Configuration Protocol (DHCP) are based on IP broadcasting. The Routing Information Protocol Ver.1 (RIPv1) uses IP broadcasting to disseminate the routing information [1]. Ethernet broadcasts are used by the Address Resolution Protocol (ARP) and the Neighbour Discovery Protocol (NDP) to translate IPv4 and IPv6 addresses respectively to MAC (Media Access Control) addresses.  
Since a source host has no information about the destination host in a broadcast transmission, any malicious host may pretend to be the intended destination host and launch several attacks in a network. An attack may originate from a host inside a Local Area Network (LAN) or from a host outside the network. However, all the attacks are targeted towards a LAN. In Section 2, we create a taxonomy of attacks that result from IPv4 broadcasting. One such important attack is the Address Resolution Protocol (ARP) poisoning problem. We discuss them in detail in Section 3.  
There are numerous papers available in the literature to solve security-related problems that result from IP broadcasting. However, all papers concentrate on solving only a particular problem. No holistic approach is made to address this problem in its entirety. Furthermore, every solution either uses cryptographic algorithms to establish a relation between an end-host and the network or uses a non-standard protocol to connect to the network. These assumptions defeat the generality offered by protocol features and the new Bring Your Own Device (BYOD) strategy. This forms the main motivation for the research work presented in this paper.  
In this paper, we follow the seven-tier architecture of the Open Systems Interconnection model (OSI) for our reference. The reader may refer to [2] for the activities of each layer in the OSI stack. If the context is clear, we denote IPv4 just as IP.  
Unlike other works available in the literature, in this paper, we provide an efficient and seamless solution for all security-related problems that are due to IPv4 broadcasting. Our proposed scheme, called PrECast (Protocol for Eliminating Broadcast) eliminates broadcasting at the network layer without losing the functionality of broadcasting. Our contributions and strengths are as follows:  
* The proposed scheme eliminates broadcasting in IPv4 networks, without losing any functionality due to IP broadcasting. Thus, our solution eliminates every security-related issue that is due to broadcasting.
* Unlike other papers available in the literature, the proposed solution is crypto-free and does not require any modification to a protocol or configuration at the client-side. Thus, our scheme does not violate any protocol standards and support BYOD.
* Implementing our scheme requires minimal configuration at the core network, and its operation is autonomous.
* Our solution is future proof and scalable. It can easily be implemented in a Software-Defined Networking (SDN) environment.  
The rest of the paper is organized as follows: In Section 2, we create a taxonomy of security-related attacks that are due to IPv4 broadcasting. One such important attack is the ARP-poisoning attack. In Section 3, we review the current solutions to the ARP-poison problem. We also highlight the strengths and weaknesses of various solutions reviewed in this paper. Section 4 deals with the design of the PrECast protocol. In Section 5, we present the performance analysis of the PrECast protocol for convergence and message complexity. In Section 6, we highlight the strength of our protocol against the protocols we reviewed here. Section 7 deals with the conclusions and future directions.