Hoda Hassan

Securing the AODV protocol using specification-based intrusion detection

This paper presents an implementation of an Intrusion Detection System (IDS) aiming to secure the AODV protocol designed for MANET. The IDS is designed as multiple static agents that run on a subset of the nodes in the network and executes a monitoring protocol that observes the process of route establishment. The monitoring protocol uses specification based intrusion detection to identify misuses to the routing messages. The IDS design is a correlation of previous work done in the field of MANET security. The IDS is implemented using ns-2 simulator and its ability to detect attacks was tested using previously devised attack scripts. Detailed specification for the runtime behavior of the AODV protocol was derived in the process of implementation

CellNet: A Bottom-Up Approach to Network Design

The ever-increasing dependence on the Internet is challenged by several factors impeding the smooth transition to the nomadic and ubiquitous future communications. These hindering factors are primarily attributed to the top-down approach in designing computer networks that resulted in adopting a layered architecture for abstracting network functionalities as well as for engineering protocols; a methodology that proved to be neither adaptable nor evolvable in response to changes in network operational requirements and technological advancements. This paper presents a bottom-up strategy for designing computer networks through i)the formalization of network design core principles, ii)the derivation of a conceptual framework for network concerns and a structural model for network building elements inspired by natural complex systems, thus introducing the Network Cell which is the network elementary building block intrinsically capable of specialization, adaptation and evolution, and iii) finally, a Cell-based network realization. Cell-based network adaptation capabilities are evaluated through simulations. Results show the awareness of UDP and TCP to path delays and the possibility of tweaking their operation accordingly.

IASM: An Integrated Attribute Similarity for complex networks generation

Complex networks are seen in different real life disciplines. They are characterized by a scale-free power-law degree distribution, a small average path length (small world phenomenon), a high average clustering coefficient, and the emergence of community structure. Most proposed complex networks models did not incorporate all of the four common properties of complex networks. Models have also neglected incorporating the heterogeneous nature of network nodes. In this paper, we propose two generation models for heterogeneous complex networks. We introduce the Integrated Attribute Similarity Model (IASM). IASM uses preferential attachment to connect nodes based on their attributes similarities integrated with nodes structural popularity (normalized degree or Eigen vector centrality). IASM proposed model is modified to increase their clustering coefficient using a triad formation step.

CORM: A reference model for future computer networks

This paper acknowledges the need for revolutionary designs to devise the Future Internet by presenting a clean-slate Concern-Oriented Reference Model (CORM) for architecting future networks. CORM is derived in accordance to the Function-Behavior-Structure engineering framework, conceiving computer networks as a distributed software-dependent complex system. CORM networks are designed along two main dimensions: a vertical dimension addressing structure and configuration of network building blocks; and a horizontal dimension addressing communication and interaction among the previously formulated building blocks. For each network dimension, CORM factors the design space into function, structure, and behavior, applying to each the principle of separation of concerns for further systematic decomposition. Perceiving the network as a complex system, CORM constructs the network recursively in a bottom-up approach starting by the network building block, whose structure and behavior are inspired by an evolutionary bacterium cell. Hence, CORM is bio-inspired, it refutes the long-endorsed concept of layering, it accounts intrinsically for emergent behavior fostering network integrity and stability. We conjecture that networks designed according to CORM-based architectures can adapt and further evolve to better fit their contexts. To justify our conjecture, we derive and simulate a CORM-based architecture for ad hoc networks.

Towards a Federated Network Architecture

The layered architecture that guided the design of the Internet is deemed inadequate as a reference model for engineering protocols for NGN. Layered protocol suites impose a strict sequential order on protocol execution conflicting with the efficient engineering of end systems, as well as failing to express vertical functional integration, the separation of control and data planes, and the distributed nature of network functions. Furthermore, protocols developed according to the layered architecture are implemented as monolithic blocks with undefined or implicit dependencies lacking flexibility to adapt to changing application requirements. We claim that NGN architecture design should be dual faceted along a vertical and a horizontal dimension. The vertical dimension addresses complexity at a network node by abstracting the communication functionality into several components and defining component interactions, while the horizontal dimension addresses the distributed nature of the network, abstracting network links into communication paths, and defining procedures for creating, maintaining, as well as exchanging data between different network components along these paths. We propose a preliminary network architecture based on component federation. We focus on the vertical decomposition of the communication functions and their interactions considering the distributed consequences of these interactions along the horizontal dimension of the network.

Routing and reliable transport layer protocols interactions in MANETs

Several research works have attempted to study the performance of TCP and SCTP in MANETS. In this paper we further aim to study the effects of these two transport layer protocols and that of the underlying routing protocols using a two-factor full factorial experimental design with replication through simulations. The routing protocols considered are AODV, DSR, and DSDV. Our motivation is that despite the efforts in comparing the different protocols at each layer separately, little is known about which layer has the greater effect on throughput in MANETS, and hence deserves further research, and how relevant the interaction between the layers is. We attempted to use mobility models to reflect realistic mobility scenarios. Our results show that the transport layer protocols have significant effect on throughput regardless of the routing layer protocol used: SCTP outperformed TCP in all cases.

Transformation of Coloured Petri Nets to UML 2 Diagrams

Business Process Modeling Notation is used by business modelers to model business processes logic and artifacts. However, it is inadequate in expressing the execution semantics of business processes and takes a process-oriented approach for modeling systems. UML, on the other hand, is known for its expressiveness to present the object-oriented approach for modeling software-based system. There is a rising need to transform business process models to flawless UML models. This paper proposes a modeling transformation technique for transforming a business process-modeling notation model to different UML diagrams, using Coloured Petri Nets (CPN) as a formal intermediate step to ensure flawless transformation. This transformation would allow modeler to take advantages of the presentation power in BPMN as well as the implementation power in UML. Furthermore, this step will bridge the gap between the different modeling notations previously mentioned.