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In the inter-domain routing infrastructure, a route leak is defined as a violation of the routing policy agreed between two Autonomous Systems (AS). Route leaks have resulted in large-scale outages on the Internet, taking down several services. Although route leaks seem a simple problem, the solution is complex because: (i) ASes consider -partially- routing policy private, (ii) lack of a formal and standard language to express routing policy and (iii) BGP lacks adequate cryptographic-based security. In this paper, we present an experimental analysis of a distributed ledger-based architecture that provides a solution to route leaks. Specifically, the routing policy is unambiguously expressed using a formal language, that is then stored in a blockchain. This decentralized architecture allows private policies and interfaces seamlessly with the current BGP infrastructure, requiring no changes to routers. We build a prototype to evaluate our proposed architecture using Hyperledger, we analyze its performance using a real-world BGP dataset. Our results show that our architecture scales linearly with relevant metrics. Additionally, we validate the architecture preventing an artificially introduced route leak in a realistic 10 AS topology. This work was supported by the Spanish MINECO under contract TEC2017-90034-C2-1-R (ALLIANCE) and the Catalan Institution for Research and Advanced Studies (ICREA).

In this paper, we present InBlock4, a blockchain-based alternative to RPKI for the provision of Route Origin validation for BGP. InBlock4 embeds an alternative trust model to protect entities obtaining a resource allocations from errors and abuses from other entities in the allocation hierarchy. InBlock4 is compatible with BGPsec. Moreover, InBlock4 can be bootstrapped using the information in the RPKI and it can coexists with RPKI-based route origin validation. In the paper, we also present a working implementation of InBlock4 for Ethereum and we quantify its performance.

The Domain Name System (DNS) is one of the most fundamental infrastructures of the Internet. However, due to its design philosophy and implementation architecture, the current DNS still suffers from the centralization problem and the data authenticity problem. In this paper, we analyze these two problems and propose a blockchain-based naming system called blockDNS to solve them simultaneously. In blockDNS, domain names can be applied and transferred freely in a decentralized way. Moreover, a lightweight verification mechanism is also proposed coupled with blockDNS. The verification mechanism allows website clients to verify the authenticity of resolution results with few overheads. Simulation results show that, compared to the Simplified Payment Verification method, blockDNS can cut down the overheads for data authenticity verification from 4.955KBytes to 380Bytes. Moreover, we also present an implementation case of blockDNS, which is compatible with the current naming system and can be deployed incrementally.

Multipath transmission control protocol (MPTCP) has attracted significant attention from standardization bodies, industrial communities, and academic communities. However, an important performance-related aspect is that MPTCP is negatively affected by packet reordering, especially in heterogeneous wireless environments. Although to improve the protocol, the proposed updated scheduling policies and congestion control methods do not solve the problem fundamentally. In this context, by breaking the strong binding between data packets and their sequence numbers, network coding has been demonstrated to be a promising solution for end-to-end multipath transmissions. However, current network coding solutions are based on batch coding without exception, and encoding and decoding operations cannot proceed unless all packets of a group have arrived. In addition, frequent generation and transmission of coding coefficients increase the delay and waste the already limited bandwidth. This paper proposes a novel pipeline network coding-based MPTCP (MPTCP-PNC) which reduces encoding and decoding delay and saves bandwidth by using innovative economic coding coefficient rules. Based on these, a quality-based distribution scheme and a corresponding transmission management policy are introduced to further improve the performance of MPTCP-PNC. Simulation tests involving video delivery over a multi-path distribution network show how MPTCP-PNC outperforms other state-of-art network coding solutions.

ObjectiveTo investigate the relationship between small intestinal bacterial overgrowth (SIBO) and the severity of hepatitis B cirrhosis. MethodsForty-seven patients with hepatitis B cirrhosis who visited Department of Gastroenterology, Zhengzhou People′s Hospital, from June 2014 to June 2015 were selected as cirrhosis group; these patients consisted of 11 Child-Pugh class A cases, 16 Child-Pugh class B cases, and 20 Child-Pugh class C cases. Fifteen healthy volunteers were selected as control group. The levels of procalcitonin, bilirubin, plasma albumin, and globulin were measured in all subjects. The lactulose hydrogen breath test (LHBT) was performed to measure small intestinal bacterial growth. Comparison of categorical data was made by chi-square test or Fisher's exact test. Comparison of normally distributed continuacs data between groups was performed by t test, The correlations of SIBO with procalcitonin, bilirubin, plasma albumin, and albumin/globulin ratio were investigated by Pearson correlation analysis. ResultsSIBO was found in 22 (46.8%) of the 47 patients with liver cirrhosis, consisting of 2 (18.1%) in the 11 Child-Pugh class A cases, 7 (43.7%) in the 16 Child-Pugh class B cases, and 13 (65.0%) in the 20 Child-Pugh class C cases. The prevalence of SIBO showed a significant difference between the controls and all patients with hepatitis B cirrhosis, Child-Pugh class B cases, or Child-Pugh class C cases (P=0.005, 0.037, or 0.001), but no significant difference between the controls and Child-Pugh class A cases (P=0556); there was a significant difference in the prevalence of SIBO between Child-Pugh class A cases and Child-Pugh class B/C cases (χ2=4.727,P=0.030). The levels of procalcitonin, bilirubin, plasma albumin, and globulin were significantly correlated with LHBT set-value (r=0.895, 0.907, -0.810, and 0.755, respectively, all P＜0.001). ConclusionThe prevalence of SIBO increases with exacerbation of liver injury in patients with hepatitis B cirrhosis. The levels of procalcitonin, bilirubin, and globulin are positively correlated with SIBO, while plasma albumin level is negatively correlated with SIBO.

With the diverse needs of mobility support with different mobility behaviors and the different approaches to mobility in future Wireless, different mobility management mechanisms at the IP layer are needed. Different mobility architectures are presented in terms of the component mobility functions of location information database functions, forwarding management functions, and identifier for session continuity. Different IP mobility mechanisms are then systematically categorized in terms of these basic functions and architectures in networks with or without separation of data and control plane or virtualization of network functions. They provide the IP layer building blocks for the diverse mobility management mechanisms needed in future cellular network designs in 5G wireless and beyond.

Tunneling technology has been widely applied in the network, but the lack of effective congestion exposure in the tunnel, seriously affect the performance of the tunnel technology. This document will focus on the tunnel scenario, to design a tunnel congestion exposure and feedback model, and the tunnel congestion marking scheme and congestion information feedback scheme. First, the document describes Tunneling Protocol, Secondly describes the congestion problems in the tunnel, Thirdly proposes a basic tunnel congestion exposure model, Finally, proposes the detail of tunnel congestion marking and feedback scheme for the model. Modifying the ECN tunnel rules of RFC3168 and RFC6040, congestion marking scheme can be applied to the feedback model. Congestion feedback scheme use GRE (Generic Routing Encapsulation) header format extension to carry the feedback information. Content and format of Congestion feedback, and the transmission of feedback information are also discussed in the document.