Network security policy models

Consideration is given to the development of security policy models for networks which can operate in a multilevel security environment. An outline is presented of an abstract security policy model which addresses the access control and information flow requirements in a multilevel network. The network security policy is formulated by drawing as much parallel as possible with the computer security policy. The model is defined, and the associated security requirements are given. The model is used to prove that the security conditions are not violated by the defined network operations. >

This project establishes a Chinese wall security policy model in the environment of cloud computing. In 1988 Brewer and Nash proposed a very nice commercial security policy in British financial world. Though the policy was well accepted, but the model was incorrect. A decade later, Dr. Lin provided a model in 2003 that meets Brewer & Nash’s Policy. One of the important components in Cloud computing is data center. In order for any company to store data in the center, a trustable security policy model is a must; Chinese wall security policy model will provide this assurance. The heart of the Chinese Wall Security Policy Model is the concept of Conflict of Interest (COI). The concept can be modeled by an anti-reflexive, symmetric and transitive binary relation. In this project, by extending Dr. Lin’s Model, we explore the security issues in the environment of cloud computing and develop a small system of the Chinese Wall Security Model.

Transaction-processing systems (TPS) are becoming increasingly more available as commercial products. However, the approaches to the issues associated with using TPS in multilevel secure environments are still in the research stage. In this article, we address the issues of multilevel security in distributed transaction-processing systems. A distributed transaction-processing system (DTPS) is a collection of a finite number of centralized transaction-processing systems connected by a computer network. Each of these transaction-processing systems is controlled by a software layer and can be accessed both remotely and locally. Properties of a DTPS, such as data replication, may have a substantial effect on the security of the system. The security policies and integrity constraints adopted at each site may result in global security having inconsistent states. We address the issues of achieving a multilevel secure DTPS, and discuss the security constraints and data replication.

Federated cloud networks are formed by federating virtual network segments from different clouds, e.g. in a hybrid cloud, into a single federated network. Such networks should be protected with a global federated cloud network security policy. The availability of network function virtualisation and service function chaining in cloud platforms offers an opportunity for implementing and enforcing global federated cloud network security policies. In this paper we describe an approach for enforcing global security policies in federated cloud networks. The approach relies on a service manifest that specifies the global network security policy. From this manifest configurations of the security functions for the different clouds of the federation are generated. This enables automated deployment and configuration of network security functions across the different clouds. The approach is illustrated with a case study where communications between trusted and untrusted clouds, e.g. public clouds, are encrypted. The paper discusses future work on implementing this architecture for the OpenStack cloud platform with the service function chaining API.

Security policy is a main mechanism of information security management. While there are a lot of security-related standards and guidelines which specify requirements for high-level security policies, implementation of network security policy still depends on interfaces provided by network security systems (NSS). Obviously, diversity of policy representation languages affects efficiency of policy deployment process. The paper proposes a concept of unification of policy rules for NSSs as a solution for the problem. The idea is based on a formal language which makes it possible to formalize network security policies independently of particular NSSs.

Computer security policies are relatively new to many organisations, particularly regarding their Information Security Management Systems (ISMS). Although their conceptual origins date back to the 1980s, verifying these policies computationally remains a significant challenge. This research proposes a new tool for the verification of ISMS policies based on the VPD methodology. This methodology assesses information security policies and their compliance with ISMS by comparing the set of directive policies (M1) with the implemented policies (M2). The case study presented in this paper involves the M2 policies implemented in the security system of the Mayor’s Office in the municipality of Funza, Cundinamarca. These are based on established standards, such as ISO 27001, ITIL best practice libraries, the OISM3 guidelines, and Colombian government regulations—particularly those aligned with standards set by the Ministry of Information and Communication Technologies (MINTIC). The main contribution of this research is the development of ESVIT, an expert system built upon the VPD methodology to support the evaluation of policies in both public and private sector entities.

Role Based Access Control (RBAC) is more and more applied to design and implement security policies in large networking systems. Although the elegance of this model, the design process of a security policy remains a challenge. The consistence and the correctness of the policy are crucial. Formal verification is one of the techniques, which can be used to prove that the designed policy is consistent. In this paper, we present a concrete formal modeling/analysis approach for RBAC policies. The modeling phase uses Colored Petri Nets (CPN) and the generated models will be analyzed using the CPN-tool. This analysis will wallow to prove many important proprieties about the RBAC security policy.

Communications networks are valuable in proportion to the trustworthy information they carry. Network security policies are designed to classify nodes as trustworthy or not with some probability of error when the true status of each node is unknown. By making an analogy with the binary symmetric channel model, properties of networks with optimal security policies are derived. Additive and multiplicative utility models with and without aversion to misclassification risk are considered.

Network security polices are essential elements in Internet security devices that provide traffic filtering, integrity, confidentiality, and authentication. Network security perimeter devices such as firewalls, IPSec, and IDS/IPS devices operate based on locally configured policies. However, configuring network security policies remains a complex and error-prone task due to rule dependency semantics and the interaction between policies in the network. This complexity is likely to increase as the network size increases. A successful deployment of a network security system requires global analysis of policy configurations of all network security devices in order to avoid policy conflicts and inconsistency. Policy conflicts may cause serious security breaches and network vulnerability such as blocking legitimate traffic, permitting unwanted traffic, and insecure data transmission. This article presents a comprehensive classification of security policy conflicts that might potentially exist in a single security device (intrapolicy conflicts) or between different network devices (interpolicy conflicts) in enterprise networks. We also show the high probability of creating such conflicts even by expert system administrators and network practitioners.

This document describes the problem space and solution requirements for developing an IP Security Policy (IPSP) configuration and management framework. The IPSP architecture provides a scalable, decentralized framework for managing, discovering and negotiating the host and network security policies that govern access, authorization, authentication, confidentiality, data integrity, and other IP Security properties. This document highlights such architectural components and presents their functional requirements.

Network traffic classification is the process of analyzing traffic flows and associating them to different categories of network applications. Network traffic classification represents an essential task in the whole chain of network security. Some of the most important and widely spread applications of traffic classification are the ability to classify encrypted traffic, the identification of malicious traffic flows, and the enforcement of security policies on the use of different applications. Passively monitoring a network utilizing low-cost and low-complexity wireless local area network (WLAN) devices is desirable. Mobile devices can be used or existing office desktops can be temporarily utilized when their computational load is low. This reduces the burden on existing network hardware. The aim of this paper is to investigate traffic classification techniques for wireless communications. To aid with intrusion detection, the key goal is to passively monitor and classify different traffic types over WLAN to ensure that network security policies are adhered to. The classification of encrypted WLAN data poses some unique challenges not normally encountered in wired traffic. WLAN traffic is analyzed for features that are then used as an input to six different machine learning (ML) algorithms for traffic classification. One of these algorithms (a Gaussian mixture model incorporating a universal background model) has not been applied to wired or wireless network classification before. The authors also propose a ML algorithm that makes use of the well-known vector quantization algorithm in conjunction with a decision tree—referred to as a TRee Adaptive Parallel Vector Quantiser. This algorithm has a number of advantages over the other ML algorithms tested and is suited to wireless traffic classification. An average F-score (harmonic mean of precision and recall) > 0.84 was achieved when training and testing on the same day across six distinct traffic types.

The use of different network security components, such as firewalls and network intrusion detection systems (NIDSs), is the dominant method to monitor and guarantee the security policy in current corporate networks. To properly configure these components, it is necessary to use several sets of security rules. Nevertheless, the existence of anomalies between those rules, particularly in distributed multi-component scenarios, is very likely to degrade the network security policy. The discovery and removal of these anomalies is a serious and complex problem to solve. In this paper, we present a complete set of mechanisms for such a management.

A model of security is presented which integrates notions of confidentiality and integrity. This model has been developed to fulfil the needs of the RSRE SMITE project because existing modeling approaches proved to be inadequate. The authors introduce the model and subsequently compare and contrast it with existing approaches. Both an inductive confidentiality property and a noninductive integrity property have been modeled. To successfully utilize the second property, the authors have used an approach whereby the noninductiveness is absent in the model, but appears in proof obligations on refinement. >

The paper describes the development of a formal security policy model in Z for the NATO Air Command and Control System (ACCS): a large, distributed, multilevel-secure system. The model was subject to manual validation, and some of the issues and lessons in both writing and validating the model are discussed. >

This paper summarizes our experiences deploying a transparent Split TCP middlebox for WiFi networks in Enterprise customer environments. Since Split TCP is nearly two decades old, we believed this would be a straightforward application of well-known technology. Reality, however, would teach us otherwise. While we began our deployment in our own office with 3,000 users, we encountered several challenges in deploying this technology at customer sites. Each customer had different network architectures, security policies, and non-negotiable requirements. In particular, modifying the network architecture was frequently impossible. Deployment challenges tended to fall into two related but distinct categories. First, making the box transparent to both clients and servers required extending the notion of transparency from beyond just layer 3 and layer 4 to include layer 2. Second, the interaction of our middlebox with other middleboxes resulted in unexpected behaviors.Our deployments supported up to 15,000 simultaneous users and lasted up to 2 years. We offer up our experiences so that others need not repeat them. We discuss some implications of our experiences on deploying network functionality in virtual environments, or Network Function Virtualization (NFV). If NFV is to be successful in real environments, these challenges will need to be overcome.