System design tools are often only available as input–output blackboxes: for a given design as input, they compute an output representing system behavior. Blackboxes are intended to be run in the forward direction. This article presents a new method of solving the “inverse design problem,” namely, given requirements or constraints on output, find an input that also optimizes an objective function. This problem is challenging for several reasons. First, blackboxes are not designed to be run in reverse. Second, inputs and outputs can be discrete and continuous. Third, finding designs concurrently satisfying a set of requirements is hard because designs satisfying individual requirements may conflict with each other. Fourth, blackbox evaluations can be expensive. Finally, evaluations can sometimes fail to produce an output due to nonconvergence of underlying numerical algorithms. This article presents CNMA, a new method of solving the inverse problem that overcomes these challenges. CNMA tries to sample only the part of the design space relevant to solving the inverse problem, leveraging the power of neural networks, mixed-integer linear programs, and a new learning-from-failure feedback loop. This article also presents a parallel version of CNMA that improves the efficiency and quality of solutions over the sequential version and tries to steer it away from local optima. CNMA’s performance is evaluated against conventional optimization methods for seven nonlinear design problems of 8 (two problems), 10, 15, 36 and 60 real-valued dimensions and one with 186 binary dimensions. Conventional methods evaluated are stable, off-the-shelf implementations of the Bayesian optimization with the Gaussian Processes, Nelder–Mead, and Random Search. The first two do not even produce a solution for problems that are high dimensional, having both discrete and continuous variables or whose blackboxes fail to return values for some inputs. CNMA produces solutions for all problems. When conventional methods do produce solutions, CNMA improves upon their performance by 1%–87%.

In this paper, we first describe the challenges of provisioning Wi-Fi equipped M2M devices, which may be behind Network Address Translation (NAT). We then articulate an automatic over-the-air provisioning mechanism that includes four steps: device discovery, user account setup for device, ESSID/IP configuration, and device registration (including NAT tunnel configuration). The mechanism enables M2M service providers to manage the registered M2M devices and allows M2M users to access these M2M devices behind NAT using a unique fully qualified domain name (FQDN). Finally, we elaborate the performance analysis and technical discussions related to the automatic provisioning mechanism.

The NGN (Next Generation Network), which can provide advanced multimedia services over an all-IP based network, has been the subject of considerable attention for several years. While there have been tremendous efforts to develop its architecture and protocols, especially for IMS, a key technology of the NGN, its wide deployment is still a long way off. However, efforts to create an advanced signaling infrastructure able to meet many requirements have resulted in a large number of functional components and interactions between these components. Thus, the carriers are trying to explore effective ways to deploy IMS while offering value-added services. As one such approach, we have proposed a self-organizing IMS. A self-organizing IMS enables IMS functional components and corresponding physical nodes to adapt dynamically and automatically based on actual conditions such as network load and available system resources while continuing IMS operation. To realize this, service continuity for users is an important requirement when a reconfiguration occurs during operation. In this paper, we propose a mechanism that will provide service continuity to users without any impact on clients by extending the SBC (Session Border Controller). Furthermore, we implement it, show its behavior and evaluate its processing time.

The integrated networking technology prototype demonstrates the capability of several emerging networking technologies to operate together seamlessly to enhance network services targeted for dynamic mobile environments such as those found in the battlefield. The prototype consists of four technologies: (1) autoconfiguration technology supports autonomous and rapid network deployment and configuration; (2) self-managed virtual network (SMVN) technology provides virtual networking capabilities for networks which do not natively support these functions; (3) integrated mobility management technology supports session continuity in the presence of node mobility; (4) assured IP QoS technology supports guarantees for mission-critical applications. The prototype is capable of operating over the various types of equipment and protocols to be utilized in battlefield networks. The prototype is designed such that network services and functions are survivable and reconfigurable. In this paper, we describe the four technologies as well as the integrated prototype in the laboratory environment.

As client/server-based network communications becomes ever-increasingly widespread with the rapid growth of the Internet, security problems have emerged as one of the most pressing issues in the Internet community. Despite the best effort of the Internet community to minimize security problems, vulnerabilities in the network still exist, and various lapses in security have demonstrated the destruction of data integrity and resource availability in the Internet. In particular, a series of occurrences of distributed denial of service (DDoS) have proven to be a challenging issue for Internet service providers (ISPs) and content providers alike. We present a novel approach, ACtive edgeTagging (ACT), which facilitates the handling of source-spoofed attacks by effectively detecting, identifying, and isolating intrusions in the network layer. Unlike the existing solutions, ACT deals with the targeted attacks efficiently without over-bearing requirements or mandatory participation of every individual network in the Internet. ACT is particularly effective for identifying and isolating attackers employing DDoS type of intrusion schemes, and it is highly scalable and extensible as well as feasible to implement in large-scale networks such as the global Internet.