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Algebraic Traceback Meets Network Coding

Pegah Sattari, Athina Markopoulou
2011 2011 International Symposium on Networking Coding  
Traceback schemes aim at identifying the source(s) of a sequence of packets and the nodes these packets have traversed. We are particularly interested in algebraic traceback, which encodes the IDs of nodes on a single path as coefficients of a polynomial in a finite field, and determines the polynomial by evaluating it at different points. So far, algebraic traceback schemes have only been developed to infer single paths, and multipath graphs have been considered as a collection of multiple
more » ... vidual paths [1], [2]. In this paper, we consider multi-path graphs that use network coding for marking, and we propose an algebraic traceback scheme that combines marks on packets from different paths for better inference. Our approach first identifies the topology by mapping the graph to a multivariate polynomial, marked on packets by intermediate nodes, and then reconstructs the node IDs within the topology by solving a system of linear equations. In addition to solving the multi-path algebraic traceback problem, for the first time efficiently, we also make the connections to two network coding problems: (i) we show that the dual of the traceback problem is a linear network coding problem; and (ii) we formulate our approach as passive topology inference with non-linear network coding.
doi:10.1109/isnetcod.2011.5978944 fatcat:5cmvu3pexvatfgo36v5ywih5m4

A Network Coding Approach to IP Traceback

Pegah Sattari, Minas Gjoka, Athina Markopoulou
2010 2010 IEEE International Symposium on Network Coding (NetCod)  
Traceback schemes aim at identifying the source(s) of a sequence of packets and the nodes these packets traversed. This is useful for tracing the sources of high volume traffic, e.g., in Distributed Denial-of-Service (DDoS) attacks. In this paper, we are particularly interested in Probabilistic Packet Marking (PPM) schemes, where intermediate nodes probabilistically mark packets with information about their identity and the receiver uses information from several packets to reconstruct the paths
more » ... they have traversed. Our work is inspired by two observations. First, PPM is essentially a coupon collector's problem [1], [2] . Second, the coupon collector's problem significantly benefits from network coding ideas [3], [4] . Based on these observations, we propose a network coding-based approach (PPM+NC) that marks packets with random linear combinations of router IDs, instead of individual router IDs. We demonstrate its benefits through analysis. We then propose a practical PPM+NC scheme based on the main PPM+NC idea, but also taking into account the limited bit budget in the IP header available for marking and other practical constraints. Simulation results show that our scheme significantly reduces the number of packets needed to reconstruct the attack graph, in both single-and multi-path scenarios, thus increasing the speed of tracing the attack back to its source(s).
doi:10.1109/netcod.2010.5487682 fatcat:fy6jdoj3kvbkxn7d4loygwsx2m

Loss Tomography in General Topologies with Network Coding

Minas Gjoka, Christina Fragouli, Pegah Sattari, Athina Markopoulou
2007 IEEE GLOBECOM 2007-2007 IEEE Global Telecommunications Conference  
Network tomography infers internal network characteristics by sending and collecting probe packets from the network edge. Traditional tomographic techniques for general topologies typically use a mesh of multicast trees and/or unicast paths to cover the entire graph, which is suboptimal from the point of view of bandwidth efficiency and estimation accuracy. In this paper, we investigate an active probing method for link loss inference in a general topology, where multiple sources and receivers
more » ... re used and intermediate nodes are equipped with network coding, in addition to unicast and multicast, capabilities. With our approach, each link is traversed by exactly one packet, which is in general a linear combination of the original probes. The receivers infer the loss rate on all links by observing not only the number but also the contents of the received probes. In this paper: (i) we propose an orientation algorithm that creates an acyclic graph with the maximum number of identifiable edges (ii) we define probe combining coding schemes and discuss some of their properties and (iii) we present simulation results over realistic topologies using Belief-Propagation (BP) algorithms.
doi:10.1109/glocom.2007.78 dblp:conf/globecom/GjokaFSM07 fatcat:gjhmiybcezcszht4nbx6hs27y4

Maximum Likelihood Estimation for Multiple-Source Loss Tomography with Network Coding

Pegah Sattari, Athina Markopoulou, Christina Fragouli
2011 2011 International Symposium on Networking Coding  
Loss tomography aims at inferring the loss rate of links in a network from end-to-end measurements. Previous work in [1] has developed optimal maximum likelihood estimators (MLEs) for link loss rates in a single-source multicast tree. However, only sub-optimal algorithms have been developed for multiple-source loss tomography [2]-[5]. In this paper, we revisit multiple-source loss tomography in tree networks with multicast and network coding capabilities, and we provide, for the first time,
more » ... complexity MLEs for the link loss rates. We also derive the rate of convergence of the estimators.
doi:10.1109/isnetcod.2011.5978946 fatcat:63poerwqg5hctj2oepatgxnlce

Active topology inference using network coding

Pegah Sattari, Christina Fragouli, Athina Markopoulou
2013 Physical Communication  
Email addresses: psattari@uci.edu (Pegah Sattari), christina.fragouli@epfl.ch (Christina Fragouli), athina@uci.edu (Athina Markopoulou) Our key intuition is that network coding introduces topology-dependent  ... 
doi:10.1016/j.phycom.2012.02.006 fatcat:iubh4vylkrfu5eu2f4mwlnflgu

Active learning of multiple source multiple destination topologies

Pegah Sattari, Maciej Kurant, Animashree Anandkumar, Athina Markopoulou, Michael Rabbat
2013 2013 47th Annual Conference on Information Sciences and Systems (CISS)  
We consider the problem of inferring the topology of a network with M sources and N receivers (hereafter referred to as an M -by-N network), by sending probes between the sources and receivers. Prior work has shown that this problem can be decomposed into two parts: first, infer smaller subnetwork components (i.e., 1-by-N 's or 2-by-2's) and then merge these components to identify the M -by-N topology. In this paper, we focus on the second part, which had previously received less attention in
more » ... e literature. In particular, we assume that a 1by-N topology is given and that all 2-by-2 components can be queried and learned using end-to-end probes. The problem is which 2-by-2's to query and how to merge them with the given 1-by-N , so as to exactly identify the 2-by-N topology, and optimize a number of performance metrics, including the number of queries (which directly translates into measurement bandwidth), time complexity, and memory usage. We provide a lower bound, ⌈ N 2 ⌉, on the number of 2-by-2's required by any active learning algorithm and propose two greedy algorithms. The first algorithm follows the framework of multiple hypothesis testing, in particular Generalized Binary Search (GBS), since our problem is one of active learning, from 2-by-2 queries. The second algorithm is called the Receiver Elimination Algorithm (REA) and follows a bottom-up approach: at every step, it selects two receivers, queries the corresponding 2-by-2, and merges it with the given 1-by-N ; it requires exactly N − 1 steps, which is much less than all N 2 possible 2-by-2's. Simulation results over synthetic and realistic topologies demonstrate that both algorithms correctly identify the 2-by-N topology and are nearoptimal, but REA is more efficient in practice.
doi:10.1109/ciss.2013.6552253 dblp:conf/ciss/SattariKAMR13 fatcat:wakmgiykird2vljwsfzo4zxhee

Active Learning of Multiple Source Multiple Destination Topologies

Pegah Sattari, Maciej Kurant, Animashree Anandkumar, Athina Markopoulou, Michael G. Rabbat
2014 IEEE Transactions on Signal Processing  
We consider the problem of inferring the topology of a network with M sources and N receivers (hereafter referred to as an M-by-N network), by sending probes between the sources and receivers. Prior work has shown that this problem can be decomposed into two parts: first, infer smaller subnetwork components (i.e., 1-by-N's or 2-by-2's) and then merge these components to identify the M-by-N topology. In this paper, we focus on the second part, which had previously received less attention in the
more » ... iterature. In particular, we assume that a 1-by-N topology is given and that all 2-by-2 components can be queried and learned using end-to-end probes. The problem is which 2-by-2's to query and how to merge them with the given 1-by-N, so as to exactly identify the 2-by-N topology, and optimize a number of performance metrics, including the number of queries (which directly translates into measurement bandwidth), time complexity, and memory usage. We provide a lower bound, N/2, on the number of 2-by-2's required by any active learning algorithm and propose two greedy algorithms. The first algorithm follows the framework of multiple hypothesis testing, in particular Generalized Binary Search (GBS), since our problem is one of active learning, from 2-by-2 queries. The second algorithm is called the Receiver Elimination Algorithm (REA) and follows a bottom-up approach: at every step, it selects two receivers, queries the corresponding 2-by-2, and merges it with the given 1-by-N; it requires exactly N-1 steps, which is much less than all N2 possible 2-by-2's. Simulation results over synthetic and realistic topologies demonstrate that both algorithms correctly identify the 2-by-N topology and are near-optimal, but REA is more efficient in practice.
doi:10.1109/tsp.2014.2304431 fatcat:ovbrr23eiffu3labyk6xkgcahi

A Network Coding Approach to Loss Tomography

Pegah Sattari, Athina Markopoulou, Christina Fragouli, Minas Gjoka
2013 IEEE Transactions on Information Theory  
Network tomography aims at inferring internal network characteristics based on measurements at the edge of the network. In loss tomography, in particular, the characteristic of interest is the loss rate of individual links and multicast and/or unicast end-to-end probes are typically used. Independently, recent advances in network coding have shown that there are advantages from allowing intermediate nodes to process and combine, in addition to just forward, packets. In this paper, we study the
more » ... roblem of loss tomography in networks with network coding capabilities. We design a framework for estimating link loss rates, which leverages network coding capabilities, and we show that it improves several aspects of tomography including the identifiability of links, the trade-off between estimation accuracy and bandwidth efficiency, and the complexity of probe path selection. We discuss the cases of inferring link loss rates in a tree topology and in a general topology. In the latter case, the benefits of our approach are even more pronounced compared to standard techniques, but we also face novel challenges, such as dealing with cycles and multiple paths between sources and receivers. Overall, this work makes the connection between active network tomography and network coding.
doi:10.1109/tit.2012.2236916 fatcat:xfbz7pkq2vhxvnthdqxxs74aze

El truco de la "magia" en los cuentos populares de Mil y una noches

Nezad soleimani .Soheila, Ashrafzadeh .Reza, Taghavi Behbahani. Majid.
2019 Dilemas Contemporáneos: Educación, Política y Valores  
According to Sattari, this sleep can be defined as a transition from a life to a new life (Sattari, 1989, 76) .  ...  The uses of enchantments, translated by Shiva Razavi, First Edition, Tehran, Dastan.  Khadish, Pegah. (2006). Morphology of magical tales, Tehran, Scientific and Cultural Publications.  ... 
doi:10.46377/dilemas.v28i1.1667 fatcat:447lvimoava7nnzdrc6aieu4i4

Assessment of antifungal effects of copper nanoparticles on the growth of the fungus Saprolegnia sp. on white fish (Rutilus frisii kutum) eggs

Pegah Kalatehjari, Mahdi Yousefian, Mohammad Ali Khalilzadeh
2015 Egyptian Journal of Aquatic Research  
Despite known risks of malachite green as a teratogen and mutagen, it is still often used as a fungicide in some countries due to its high efficacy in controlling fungal infections (Sattari and Roustayi  ... 
doi:10.1016/j.ejar.2015.07.004 fatcat:viihquceancj3ojcgd4sadjfgi

Persistent Women Poets of Iran: Their Growth Through Hardships

Md Mumit Al Rashid, Tanjina Binte Nur
2022 Social Science Review  
From the second half of the nineteenth century, Iran came in direct contact with the Western world, particularly Europe (Sattari, 2009) .  ...  Poets like Shideh Taami, Khatre Hejazi, Fereshteh Sari, Nazanin Nezami Shahidi, Nahid Kabiri, Shiva Arastuu'ii, Roya Taftii, Pegah Ahmadi, Roza Jamali, Farakhandeh Hajizadeh, Hila Sadighi are the trendsetters  ... 
doi:10.3329/ssr.v38i1.56526 fatcat:5ahmmohow5at5brxg4hcgbb72e

Comparison of the Level of Substance P and Neurokinin A in Gingival Crevicular Fluid of Sound and Symptomatic Carious Primary Teeth by ELISA

Alireza Heidari, Mehdi Shahrabi, Marzieh Salehi, Shahrabi, Mehdi Ghandehari, Pegah Rahbar, M Shahrabi
2017 unpublished
In studies on coronal pulpal tissue, such as the studies by Rodd and Boissonade [21], Goodis et al [22] and Sattari et al [13], the level of SP in painful teeth was higher than that in asymptomatic  ... 
fatcat:5fc3jcw5lfbvlfkwe7e3ee3g4e

Furfural production in a biphasic system using a carbonaceous solid acid catalyst

Gerardo Gómez Millán, Josphat Phir, Mikko Mäkelä, Thad Maloney, Alina M. Balu, Antonio Pineda, Jordi Llorca, Herbert Sixta
2019 Applied Catalysis A : General  
Gharagheizi F., Sattari M., Angaji M. T. Effect of calculation method on values of hansen solubility parameters of polymers. 2006. Polymer Bulletin 57(3):377-84.  ...  Carlo, Carlos, Dou Jinze, Elsa, Estefania, Farhan, Ghazaleh, Guillaume, Joanna, Juanjo, Kaarlo, Kaniz, Karl, Kyösti, Lê Huy, Leena, Leonardo, Ling Wang, Marc, Marianna, Michael, Mikko, Olga, Panagiotis, Pegah  ... 
doi:10.1016/j.apcata.2019.117180 fatcat:nr2r7e6jcvgblhuxmloortsc5e