Packet Creation Research Articles

Promotion and Tenure Database Creation and Utilization: A 12-Year History.

Trends in faculty demographic composition, promotion success, and retention are important considerations in Academic Health Centers (AHC). This paper reviews the design, implementation, and utility of a faculty promotion and tenure (P&T) database (PROMO/TE©) over 12years in a large southwestern academic health center. Review of the system design, portfolio creation, P&T tracking, interface with other faculty databases, and lessons learned will be offered. PROMO/TE© was developed to improve the P&T packet creation, application, and review process in one College and was expanded to other colleges at the AHC. The PROMO/TE© system is integrated with Workday® and FACFACTS© to track trends in recruitment, attrition, and P&T trends across gender, underrepresented minorities, and other subgroups. PROMO/TE© has several advantages including improving communication, transparency, uniformity, and efficiency in the P&T packet creation, application, and review process. Increased cost savings ($217,198 annually) were noted with elimination of hard copy packets and decreased time spent. The first college reviewed 743 dossiers in the PROMO/TE© system since its creation in 2012 and there has been on average a 10% increase in P&T approvals since its inception. PROMO/TE© facilitates and tracks trends in the P&T process and has many benefits as well as significant cost savings. PROMO/TE© serves as a potential model for other institutions.

Micro-Satellite Systems Design, Integration, and Flight.

Within the past decade, the aerospace engineering industry has evolved beyond the constraints of using single, large, custom satellites. Due to the increased reliability and robustness of commercial, off-the-shelf printed circuit board components, missions have instead transitioned towards deploying swarms of smaller satellites. Such an approach significantly decreases the mission cost by reducing custom engineering and deployment expenses. Nanosatellites can be quickly developed with a more modular design at lower risk. The Alpha mission at the Cornell University Space Systems Studio is fabricated in this manner. However, for the purpose of development, the initial proof of concept included a two-satellite system. The manuscript will discuss system engineering approaches used to model and mature the design of the pilot satellite. The two systems that will be primarily focused on are the attitude control system of the carrier nanosatellite and the radio frequency communications on the excreted femto-satellites. Milestones achieved include ChipSat to ChipSat communication, ChipSat to ground station communication, packet creation, error correction, appending a preamble, and filtering the signal. Other achievements include controller traceability/verification and validation, software rigidity tests, hardware endurance testing, Kane damper, and inertial measurement unit tuning. These developments matured the technological readiness level (TRL) of systems in preparation for satellite deployment.

Satellite-Enabled Internet of Remote Things Network Transmits Field Data from the Most Remote Areas of the Tibetan Plateau.

In this article, we employed a satellite-enabled Internet of Remote Things (IoRT) network as a promising solution to retrieve data in the most remote areas of interest, where public networks are absent. This article presents a system network based on the satellite-enabled IoRT, a new paradigm that defines a network where each environmental monitoring device can autonomously establish a network with a remote data center. The Xingyun satellite constellation was employed for data retrieval on the Tibetan Plateau (TP). The monitoring system was mainly composed of a ground Internet of Things (IoT) terminal that was built with satellite transceivers, environmental monitoring devices, and system software. We deployed five of these newly developed terminals in harsh areas to monitor environmental variables, and accordingly, air temperature and relative humidity, precipitation, snow depth, land surface temperature, tree stemflow rate, and photosynthetically active radiation were retrieved with the satellite-enabled IoRT network. Field experiments were conducted to evaluate the performance of the proposed system network, and the results indicated that the average time delay with and without the packet creation mode reached 32 and 32.7 s, respectively, and the average packet loss rate with and without the packet creation mode reached 5.63% and 4.48%, respectively. The successful implementation of the satellite-enabled IoRT network for the rapid retrieval of monitoring data in remote glacier, forestland, and canyon areas at very high altitudes on the TP provides an entirely new and revolutionary data retrieval means for backhauling data from remote areas of interest.

MKIPS: MKI‐based protocol steganography method in SRTP

This paper presents master key identifier based protocol steganography (MKIPS), a new approach toward creating a covert channel within the Secure Real-time Transfer Protocol, also known as SRTP. This can be achieved using the ability of the sender of Voice-over-Internet Protocol packets to select a master key from a pre-shared list of available cryptographic keys. This list is handed to the SRTP sender and receiver by an external key management protocol during session initiation. In this work, by intelligent utilization of the master key identifier field in the SRTP packet creation process, a covert channel is created. The proposed covert channel can reach a relatively high transfer rate, and its capacity may vary based on the underlying SRTP channel properties. In comparison to existing data embedding methods in SRTP, MKIPS can convey a secret message without adding to the traffic overhead of the channel and packet loss in the destination. Additionally, the proposed covert channel is as robust as its underlying user datagram protocol channel.

SIPAV-SDN: Source Internet Protocol Address Validation for Software Defined Network

SDN technology is becoming every day more popular and big data centers and organizational networks have started deploying for its advantages. Current development of SDN network relies on target host IP address of packet and OFSwitches ignores checking of source host IP. SDN has separated control planes and data planes and OpenFlow protocol enabled switches are used as packet forwarding devices. The SDN controller controls flow of data packet through forwarding devices and when these are turned on, do not have any control and defense. The devices are not able to handle packet arriving from connected host. In this case, data packets of hosts are sent to the controller forwarding device for inspection and control packet creation for data packet and setting up required matching entries in flow table of forwarding device for such type of data packets generated by the hosts. The attackers can generate packets with Spoofed source IP address and perform various types of attacks. In this research paper, we offer a scheme as Source IP Address Validation for Software Defined Network (SIPAV-SDN) to check packet’s source host IP address by binding source host IP Address and MAC address with switch port. It maintains a HostTable at Controller for verification of source host IP and MAC with switch port and only forwards the packets which have valid sources host IP address. We also simulated SIPAV-SDN with hybrid SDN network and experiment results have shown that it achieved 100% packet filtering accuracy for IP spoofed TCP, UDP and ICMP packet attacks. We used python programming language for RYU controller in Mininet network emulator.

Minimizing End-to-End Delay on Real-Time Applications

In real time communication system, packets of lower prioritized flows suffer a longer queuing delay than the packets having higher priority. As a result, they reach at the destination in a long end-to-end delay and become less useful. In this paper, we have proposed a real time packet scheduling technique to minimize overall end-to-end delay among multiple flows. Here, elapsed time plays a major role to calculate priority of a packet. The packets, already spent a long queuing delay are re-assigned to lower priority. Also, the model reduces the priority of the higher prioritized packets when they are very early and approaching to the destination node. This model gives more importance to middle aged packets (neither too early nor too late with respect to packet creation and deadline of packet receiving) so that they can reach the destination within time bound. The model is experimented using NS-2 and performance has been compared with other queuing policies. Performance evaluation of this model exhibits moderated end-to-end latency of the flows and works more efficiently than other techniques.

Absolute timing of the photoelectric effect.

Photoemission spectroscopy is central to understanding the inner workings of condensed matter, from simple metals and semiconductors to complex materials such as Mott insulators and superconductors1. Most state-of-the-art knowledge about such solids stems from spectroscopic investigations, and use of subfemtosecond light pulses can provide a time-domain perspective. For example, attosecond (10-18 seconds) metrology allows electron wave packet creation, transport and scattering to be followed on atomic length scales and on attosecond timescales2-7. However, previous studies could not disclose the duration of these processes, because the arrival time of the photons was not known with attosecond precision. Here we show that this main source of ambiguity can be overcome by introducing the atomic chronoscope method, which references all measured timings to the moment of light-pulse arrival and therefore provides absolute timing of the processes under scrutiny. Our proof-of-principle experiment reveals that photoemission from the tungsten conduction band can proceed faster than previously anticipated. By contrast, the duration of electron emanation from core states is correctly described by semiclassical modelling. These findings highlight the necessity of treating the origin, initial excitation and transport of electrons in advanced modelling of the attosecond response of solids, and our absolute data provide a benchmark. Starting from a robustly characterized surface, we then extend attosecond spectroscopy towards isolating the emission properties of atomic adsorbates on surfaces and demonstrate that these act as photoemitters with instantaneous response. We also find that the tungsten core-electron timing remains unchanged by the adsorption of less than one monolayer of dielectric atoms, providing a starting point for the exploration of excitation and charge migration in technologically and biologically relevant adsorbate systems.

Test Packet Generation Based on Firewall Policies

Systems are getting larger and more complicated, yet directors depend on standard tools such as called ping and track path to debug issues. We recommend an computerized and methodical strategy for examining and debugging networks called “Automatic Analyze Bundle Generation” (ATPG). ATPG flows wireless router configurations and produces a device-independent design. The design is used to produce a lowest set of test packages to (minimally) work out every link in the system or (maximally) work out every concept in the system. Analyze packages are sent regularly, and recognized problems induce a individual procedure to localize the mistake. ATPG can identify both effective (e.g., wrong firewall program rule) and efficiency issues (e.g., crowded queue). We will only consider action mistakes because they cover most likely failing circumstances and can be recognized using only one test packet per concept. A wrong beneficial is the case where a deal is associated with a authentic customer who is obstructed because of a name or another coordinate. False advantages cannot be completely prevented; however, they can be reduced by using innovative software. The false-positive amount shows the efficiency of the system. A 5% false-positive amount on 1 million dealings would result in the recognition of fifty million wrong advantages. Our trial results show effective several packages for different concept components for automated packet creation.

Production and manipulation of wave packets from ultracold atoms in an optical lattice

Within the combined potential of an optical lattice and a harmonic magnetic trap, it is possible to form matter wave packets by intensity modulation of the lattice. An analysis of the production and motion of these wave packets provides a detailed understanding of the dynamical evolution of the system. The modulation technique also allows for a controllable transfer (deexcitation) of atoms from such wave packets to a state bound by the lattice. Thus, it acts as a beam splitter for matter waves that can selectively address different bands, enabling the preparation of atoms in localized states. The combination of wave packet creation and deexcitation closely resembles the well-known method of pump-probe spectroscopy. Here, we use the deexcitation for spectroscopy of the anharmonicity of the combined potential. Finally, we demonstrate that lattice modulation can be used to excite matter wave packets to even higher momenta, producing fast wave packets with potential applications in precision measurements.

Positioning of Bound Electron Wave Packets in Molecules Revealed by High-Harmonic Spectroscopy

By solution of the time-dependent two-electron Schrödinger equation, we demonstrate that strong-field ionization in combination with electron correlation can localize bound electron wave packets in molecules. The wave packet creation is revealed by the emission spectrum in high-order harmonic generation, which is sensitive to the ionization and recombination phase difference between different ionization channels. For hydrogen molecules at stretched internuclear distance, we find that the ionization phase difference between the gerade and ungerade channels is in the range from π and 1.5π, indicating that the bound wave packet either is initially on the same side as the outgoing electron or is delocalized.

Network in a Box: Facilitating problem‐based learning through network emulation

AbstractProblem‐based learning (PBL) is a pedagogical method that challenges students to “learn how to learn” by working cooperatively in groups to develop solutions to real world problems. Network in a Box (NiB) is a unique, engineering‐oriented effort to employ PBL in core computer networks curriculum. Developed as an open‐ended exercise in PBL, NiB sets a learning environment in which student teams design and implement a network emulator using off‐the‐shelf hardware and open‐source software. The aims of this article are twofold. The first goal of this article is to catalogue our efforts at San Diego State University in implementing PBL in a computer networks engineering course. The second goal of this article is to introduce the NiB project as a viable example of PBL in the field of computer networks. This project not only arms students with a good understanding of network impairments but also provides the knowledge of low level packet processing, packet creation, packet injection into the network, meeting real time processing requirements of packet processing and packet filtering. By arming students with an understanding of network impairments, a working knowledge of low‐level packet processing, packet creation, packet injection, and their processing requirements, NiB serves as a model introduction of PBL into the field of computer networks engineering. In this article we disseminate the product specification and system design as an educational and research utility along with an assessment of this project as perceived by students over several semesters. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 19: 433–446, 2011

Unveiling the nonadiabatic rotational excitation process in a symmetric-top molecule induced by two intense laser pulses

We experimentally investigate the nonadiabatic rotational excitation process of a symmetric-top molecule, benzene, in the electronic ground state irradiated by intense nonresonant ultrafast laser fields. The initial rotational-state distribution was restricted mostly to the five lowest levels with different nuclear spin modifications by an extensive adiabatic cooling with the rotational temperature well below 1 K, and distributions after the interaction with a femtosecond double-pulse pair (3-5 TW/cm(2) each with 160 fs duration) with time delays were probed in a quantum-state resolved manner by employing resonant enhanced multiphoton ionization via the S(1) ← S(0) 6(0) (1) vibronic transition. Populations of 10 rotational levels with J ranging from 0 to 4 and K from 0 to 3 were examined to show an oscillatory dependence on the time delay between the two pulses. Fourier analysis of the beat signals provides the coupling strengths between the constituent levels of the rotational wave packets created by the nonadiabatic excitation. These data are in good agreement with the results from quantum mechanical calculations, evidencing stepwise excitation pathways in the wave packet creation with ΔJ = 2 in the K = 0 stack while ΔJ = 1 and 2 in the K > 0 stacks.

An efficient approach of controlling traffic congestion in scale-free networks

We propose and study a model of traffic in communication networks. The underlying network has a structure that is tunable between a scale-free growing network with preferential attachments and a random growing network. To model realistic situations where different nodes in a network may have different capabilities, the message or packet creation and delivering rates at a node are assumed to depend on the degree of the node. Noting that congestions are more likely to take place at the nodes with high degrees in networks with scale-free character, an efficient approach of selectively enhancing the message-processing capability of a small fraction (e.g. 3%) of the nodes is shown to perform just as good as enhancing the capability of all nodes. The interplay between the creation rate and the delivering rate in determining non-congested or congested traffic in a network is studied more numerically and analytically.

Analysis of power spectrum and [formula omitted] type power law in a complex computer network model

The computer network, as a complex nonlinear system, exhibits plenty of nonlinear complexities phenomena. More and more researchers have been attracted to these exciting dynamic behaviors. In general, computer simulation studies are widely used in the researches on network dynamics. Unfortunately, too simple and regular topologies are adopted in these network models. It inevitably results in the fact that some important complexities behaviors in a real computer network may not emerge in most of computer experimental studies. In this paper, the phase transition phenomena between the packet creation rate and the lifetime of packet, on basis of more realistic computer network models composed of the Transit–Stub topology and the proposed mechanism of packet traffic, are explored. To illustrate the fluctuation of packets more clearly, a power spectrum is made and the 1/f type power law is found. Finally, simulation results and some research emphases in the future are discussed.

Information transfer and phase transitions in a model of internet traffic

In a recent study, Ohira and Sawatari presented a simple model of computer network traffic dynamics. These authors showed that a phase transition point is present separating the low-traffic phase with no congestion from the congestion phase as the packet creation rate increases. We further investigated this model by relaxing the network topology using a random location of routers. It is shown that the model exhibits nontrivial scaling properties close to the critical point, which reproduce some of the observed real Internet features. At criticality, the net shows maximum information transfer and efficiency. It is shown that some of the key properties of this model are shared by highway traffic models, as previously conjectured by some authors. The relevance to Internet dynamics and to the performance of parallel arrays of processors is discussed.

Phase transition in a computer network traffic model

We propose and study here a simple model of computer network traffic that can exhibit a phase transition from a low to high congestion state measured in terms of average travel time of packets as a function of the packet creation rate in the network. In the model, packets are generated with destination addresses, and are transferred from one router to another toward their destinations. The routers are capable of queuing packets and autonomously selecting a path to the next router for a packet. Through simulations on a two-dimensional lattice model network, we found that the phase transition point into the congestion phase depends on how each router chooses a path for the packets in its queue. In particular, an appropriate randomness in path selection can shift the onset of traffic congestion to accommodate more packets in the model network.