Self-Synchronized Encryption for Physical Layer in Gigabit Ethernet Optical Links

In this work a new self-synchronized symmetric encryption solution for high speed communication systems necessary to preserve the format of the plaintext is proposed, developed and tested. This new encryption mechanism is based on the block cipher operation mode called PSCFB (Pipelined Statistical Cipher Feedback) and the modulo operation. The confidentiality of this mode is analyzed in terms of its IND-CPA (Indistinguishability under Chosen-Plaintext Attack) advantage, concluding that it can be considered secure in the same way as traditional modes are. The encryption system has been integrated in the physical layer of a 1000Base-X Gigabit Ethernet Interface, where the 8b/10b symbol flow is encrypted at line rate. Moreover, an implementation of the proposed system has been carried out in an FPGA (Field Programmable Gate Array) device. Finally, an encrypted optical link has been tested with real Ethernet frames, getting maximum throughput and protecting the data traffic from passive eavesdroppers

Chaotic Encryption for 10-Gb Ethernet Optical Links

In this paper, a new physical layer encryption method for optical 10-Gb Ethernet links is proposed. Necessary modifications to introduce encryption in Ethernet 10GBase-R standard have been considered. This security enhancement has consisted of a symmetric streaming encryption of the 64b/66b data flow at physical coding sublayer level thanks to two keystream generators based on a chaotic algorithm. The overall system has been implemented and tested in a field programmable gate array. Ethernet traffic has been encrypted, transmitted, and decrypted over a multimode optical link. Experimental results are analyzed concluding that it is possible to cipher traffic at this level and hide the complete Ethernet traffic pattern from any passive eavesdropper. In addition, no overhead is introduced during encryption, getting no losses in the total throughput

Chaos-Based Bitwise Dynamical Pseudorandom Number Generator on FPGA

In this paper, a new pseudorandom number generator (PRNG) based on the logistic map has been proposed. To prevent the system to fall into short period orbits as well as increasing the randomness of the generated sequences, the proposed algorithm dynamically changes the parameters of the chaotic system. This PRNG has been implemented in a Virtex 7 field-programmable gate array (FPGA) with a 32-bit fixed point precision, using a total of 510 lookup tables (LUTs) and 120 registers. The sequences generated by the proposed algorithm have been subjected to the National Institute of Standards and Technology (NIST) randomness tests, passing all of them. By comparing the randomness with the sequences generated by a raw 32-bit logistic map, it is shown that, by using only an additional 16% of LUTs, the proposed PRNG obtains a much better performance in terms of randomness, increasing the NIST passing rate from 0.252 to 0.989. Finally, the proposed bitwise dynamical PRNG is compared with other chaos-based realizations previously proposed, showing great improvement in terms of resources and randomness

Diversification of importin-α isoforms in cellular trafficking and disease states.

The human genome encodes seven isoforms of importin α which are grouped into three subfamilies known as α1, α2 and α3. All isoforms share a fundamentally conserved architecture that consists of an N-terminal, autoinhibitory, importin-β-binding (IBB) domain and a C-terminal Arm (Armadillo)-core that associates with nuclear localization signal (NLS) cargoes. Despite striking similarity in amino acid sequence and 3D structure, importin-α isoforms display remarkable substrate specificity in vivo. In the present review, we look at key differences among importin-α isoforms and provide a comprehensive inventory of known viral and cellular cargoes that have been shown to associate preferentially with specific isoforms. We illustrate how the diversification of the adaptor importin α into seven isoforms expands the dynamic range and regulatory control of nucleocytoplasmic transport, offering unexpected opportunities for pharmacological intervention. The emerging view of importin α is that of a key signalling molecule, with isoforms that confer preferential nuclear entry and spatiotemporal specificity on viral and cellular cargoes directly linked to human diseases

Cellular Human CLE/C14orf166 Protein Interacts with Influenza Virus Polymerase and Is Required for Viral Replication ▿

The influenza A virus polymerase associates with a number of cellular transcription-related factors, including RNA polymerase II. We previously described the interaction of influenza virus polymerase subunit PA with human CLE/C14orf166 protein (hCLE), a positive modulator of this cellular RNA polymerase. Here, we show that hCLE also interacts with the influenza virus polymerase complex and colocalizes with viral ribonucleoproteins. Silencing of hCLE causes reduction of viral polymerase activity, viral RNA transcription and replication, virus titer, and viral particle production. Altogether, these findings indicate that the cellular transcription factor hCLE is an important protein for influenza virus replication

Structural Characterization of the Viral and cRNA Panhandle Motifs from the Infectious Salmon Anemia Virus ▿

Infectious salmon anemia virus (ISAV) has emerged as a virus of great concern to the aquaculture industry since it can lead to highly contagious and lethal infections in farm-raised salmon populations. While little is known about the transcription/replication cycle of ISAV, initial evidence suggests that it follows molecular mechanisms similar to those found in other orthomyxoviruses, which include the highly pathogenic influenza A (inf A) virus. During the life cycle of orthomyxoviruses, a panhandle structure is formed by the pairing of the conserved 5′ and 3′ ends of each genomic RNA. This structural motif serves both as a promoter of the viral RNA (vRNA)-dependent RNA polymerase and as a regulatory element in the transcription/replication cycle. As a first step toward characterizing the structure of the ISAV panhandle, here we have determined the secondary structures of the vRNA and the cRNA panhandles on the basis of solution nuclear magnetic resonance (NMR) and thermal melting data. The vRNA panhandle is distinguished by three noncanonical U·G pairs and one U·U pair in two stem helices that are linked by a highly stacked internal loop. For the cRNA panhandle, a contiguous stem helix with a protonated C·A pair near the terminus and tandem downstream U·U pairs was found. The observed noncanonical base pairs and base stacking features of the ISAV RNA panhandle motif provide the first insight into structural features that may govern recognition by the viral RNA polymerase