The design of the IP protocol makes it difficult to reliably identify the originator of an IP packet. Even in the absence of any deliberate attempt to disguise a packet's origin, widespread packet forwarding techniques such as NAT and encapsulation may obscure the packet's true source. Techniques have been developed to determine the source of large packet flows, but, to date, no system has been presented to track individual packets in an efficient, scalable fashion. We present a hash-based technique for IP traceback that generates audit trails for traffic within the network, and can trace the origin of a single IP packet delivered by the network in the recent past. We demonstrate that the system is effective, space efficient (requiring approximately 0.5% of the link capacity per unit time in storage), and implementable in current or next-generation routing hardware. We present both analytic and simulation results showing the system's effectiveness.

The Border Gateway Protocol (BGP), which is used to distribute routing information between autonomous systems (ASes), is a critical component of the Internet's routing infrastructure. It is highly vulnerable to a variety of malicious attacks, due to the lack of a secure means of verifying the authenticity and legitimacy of BGP control traffic. This paper describes a secure, scalable, deployable architecture (S-BGP) for an authorization and authentication system that addresses most of the security problems associated with BGP. The paper discusses the vulnerabilities and security requirements associated with BGP, describes the S-BGP countermeasures, and explains how they address these vulnerabilities and requirements. In addition, this paper provides a comparison of this architecture to other approaches that have been proposed, analyzes the performance implications of the proposed countermeasures, and addresses operational issues.

Summary form only given. The history of network security is outlined by looking at technology in 1979 and comparing it with that of 1999. The following areas are included: crypto based net security; access control and authentication; and security protocols.

The need of scaleable key management support for Mobile IP, especially the route‐optimized Mobile IP, is well known. In this paper, we present the design and the implementation of a public key management system that can be used with IETF basic and route optimized Mobile IP. The system, known as the Mobile IP Security (MoIPS) system, was built upon a DNS based X.509 Public Key Infrastructure and the innovation in cross certification and zero‐message key generation. The system can supply cryptographic keys for authenticating Mobile IPv.4 location management messages and establishing IPSec tunnels for Mobile IP redirected packets. It can also be used to augment firewall traversal of Mobile IP datagrams. A FreeBSD UNIX implementation of the MoIPS prototype is available for non‐commercial uses.

This paper describes the work undertaken to secure Nimrod, a complex and sophisticated routing system that unifies interior and exterior routing functions. The focus of this work is countering attacks that would degrade or deny service to network subscribers. The work began with an analysis of security requirements for Nimrod, based on a hybrid approach that refines top-down requirements generation with an understanding of attack scenarios and the capabilities and limitations of countermeasures. The countermeasures selected for use here include several newly developed sequence integrity mechanisms, plus a protocol for shared secret establishment. A novel aspect of this work is the protection of subscriber traffic in support of the overall communication availability security goal.

Previous work (e.g., [1], [2]) has characterized communication security requirements in connection-oriented (virtual circuit) environments supporting applications such as interactive communication and file transfer. This work has developed protocols to achieve these requirements using conventional ciphers (CC's) such as the NBS data encryption standard (DES) [3]. More recently, several authors [4]-[6] have analyzed key distribution protocols for such environments based on CC's and on public-key ciphers (PKC's) such as the RSA algorithm [7], noting similarities in form, function, and vulnerability. Advances in satellite and packet radio technology [8], [9] and the development of high-speed, local area networks [10] have stimulated interest in broadcast protocols for various applications. This article examines security requirements for a simple broadcast scenario characteristic of some of these applications and develops protocols for achieving these requirements. Two sets of protocols, one based on CC's and the other based on PKC's, are developed and analyzed in terms of functionality and performance.

This paper develops a virtual connection model, complete with intruder, for interactive terminal-host communication and presents a set of protection goals that characterize the security that can be provided for a physically unsecured connection. Fundamental requirements for protocols that achieve these goals and the role of encryption in the design of such protocols are examined. Functional and security constraints on positioning of protection protocols in a communication system and the impact of positioning on the design of secure operating systems are discussed.