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Martin Hell
Добавлен 7 июл 2020
Communicating Cybersecurity Vulnerability Information: A Producer-Acquirer Case Study
Presentation of paper on Profes 2021.
Authors: Martin Hell (Lund University) and Martin Höst (Lund University)
Title: Communicating Cybersecurity Vulnerability Information: A Producer-Acquirer Case Study
Presentation by Martin Hell
Authors: Martin Hell (Lund University) and Martin Höst (Lund University)
Title: Communicating Cybersecurity Vulnerability Information: A Producer-Acquirer Case Study
Presentation by Martin Hell
Просмотров: 113
Видео
Using Program Analysis to Identify the Use of Vulnerable Functions - SECRYPT 2021
Просмотров 1443 года назад
Conference presentation by Rasmus Hagberg.
The SMARTY Research Project
Просмотров 1483 года назад
A short overview of a research project conducted at Lund University. The project is entitled SMARTY: Secure Software Update Deployment for the Smart City. It is a collaboration between the Electrical and Information Technology department and the Computer Science department. It is supported by the Swedish Foundation for Strategic Research.
Bitcoin technology explained in a simple way
Просмотров 1864 года назад
An introductory overview of the technology that enables Bitcoin. The underlying technical problems and challenges are given and I show how Bitcoin solves these problems. The description is nontechnical, yet explains how the technical challenges are handled by the transactions and the blockchain.
5.5 Binary, Octal and Hexadecimal Representation of Numbers
Просмотров 9144 года назад
In digital circuits, numbers are treated in their binary form. Here we introduce the binary, octal, and hexadecimal representation of numbers. We also show how one can be derived from the other.
14.6 Observer Canonical Form for LFSRs
Просмотров 1,2 тыс.4 года назад
We define the observer canonical form for an LFSR and show that when clocking an LFSR of this form, it is the same as performing the division P(D)/C(D).
14.7 Period of Connection Polynomial
Просмотров 1,3 тыс.4 года назад
We define the period of the connection polynomial and link this period to the period of the sequence generated by the LFSR.
14.5 Derive P(D) from Starting State
Просмотров 1,3 тыс.4 года назад
With the connection polynomial and the starting state, we show how we can derive the polynomial P(D).
14.3 LFSR Theorem and Euclid's Algorithm for LFSRs
Просмотров 2,1 тыс.4 года назад
The LFSR theorem connects the sequence generated by the LFSR with the connection polynomial. We state the theorem and show how we can use Euclid's algorithm to find the shortest LFSR that generates a given sequence.
14.4 Derive Starting State From P(D)
Просмотров 1,4 тыс.4 года назад
With the connection polynomial and P(D), we show how we can derive the starting state of the LFSR.
14.1 LFSR - Definition and State Transitions
Просмотров 2 тыс.4 года назад
We define the linear feedback shift register and show how it implements transitions between states.
13.4 Rank, Diagnostic Matrix and Reduced Form
Просмотров 1,5 тыс.4 года назад
To understand how we can reduce the linear circuit, we need to define the rank of a matrix and define the diagnostic matrix. This will allow us to define the reduced form of the matrices A, B, C, and H.
14.2 LFSR - Connection Polynomial and Recursion
Просмотров 3,9 тыс.4 года назад
The connection polynomial defines the LFSR. We define this polynomial and give a few examples of LFSRs and their connection polynomial. We also prove the shift register recursion.
13.7 D-transform of Periodic Sequences
Просмотров 1,7 тыс.4 года назад
We introduce periodic sequences and show how such infinite sequences can be written on the D-transform.
13.5 Example of a Linear Sequential Circuit, Part 2 - Reducing the Circuit
Просмотров 1,5 тыс.4 года назад
We continue the example by showing how the reduced form of our matrices can be computed and finally give the reduced circuit.
13.3 Example of a Linear Sequential Circuit, Part 1 - Defining the Circuit
Просмотров 1,3 тыс.4 года назад
13.3 Example of a Linear Sequential Circuit, Part 1 - Defining the Circuit
11.8 The D-element - Cascading Two Latches
Просмотров 1,5 тыс.4 года назад
11.8 The D-element - Cascading Two Latches
12.1 Programmable Logic Array (PLA)
Просмотров 1,3 тыс.4 года назад
12.1 Programmable Logic Array (PLA)
11.7 The Latch - A Simple Memory Circuit
Просмотров 1,5 тыс.4 года назад
11.7 The Latch - A Simple Memory Circuit
11.6 Asynchronous Sequential Circuit
Просмотров 1,1 тыс.4 года назад
11.6 Asynchronous Sequential Circuit
11.3 Asynchronously Realisable Graphs
Просмотров 1,3 тыс.4 года назад
11.3 Asynchronously Realisable Graphs
Thanks a lot
Awesome, really appreciate this, helped a lot, thanks :)
Thanks a lot for this series, it has been very helpful!
Now I am starting to wonder if all the state transition graphs except for 00...0 have the same cylce length. But I feel that at least, any cycle length would have to divide (2^N - 1) with N as the number of slots in the register.
If they have the same cycle length, then this length will divide 2^n - 1, but it will depend on the polynomial that defines the LFSR. There are three cases, primitive, irreducible and reducible polynomials. If the polynomial is primitive then there is a maximum length sequence of length 2^n - 1. If it is irreducible (it can not be factored into the product of polynomials of smaller degree), then all sequences are the same length, which of course must divide 2^n - 1. If they are reducible (it can be factored), then the cycle lengths are more complex and will depend on the cycle lengths of the irreducible polynomials that it is factored into. There is old and well established theory on this. The first I know of is from 1958 by Birdsall and Ristenbatt (introduction to linear and shift-register generated sequences). It is actually quite readable and you will find the PDF on Google scholar.
@@martinhell4596 Awesome, thank you so much!
CNF var ju inte så svårt ju!
where are you martin i miss your videos
Great Job!
Interesting. How did you develop your definition for addition? EDIT: Nvm, it seems you explain it in the video about Boolean Algebra <-> Boolean Rings
Very nice video, clear explanation! You deserve more attention.
great video
Thank you very much for this video, really helped my on my final exam! 😁
weldon
eeldon
nice
LOL
2:12 “3 times 3 is idempotent because it equals 3”? maybe wish the multiplication was explained (at the “idempotency”-table)
It is a ring operation, so it is modulo 6. 3x3 = 3 mod 6.
mhm
I think you made a careless mistake at 1:25 . I think it is not "x1y1" but "x1x2".
Yes. Thanks for pointing it out. It should of course be x1x2.
Hi Martin.. your presentation was very nice.. i have one doubt. In a Boolean table a+b equation, is it solve for all the elements in that table? . If you solve only 4+1. In the same way I will try to solve 3+4 but it is not working.can you help me to solve that.
Hi. It will work. You have 3 + 4 = 3 (+) 4 (+) 4 (x) (3 (x) 4) mod 6 = 7 (+) 48 mod 6 = 55 mod 6 = 1 mod 6. I hope the notation makes sense.
Thank you sir. You explained better than my teacher :)
you are awsome
Ska inte C vara x3x5 och inte x2x5?
Jo, du har rätt.
This is pretty cool.
Just a note; In the last part of the video its written : "rj = sjn1 + tjn3 for all j", but should be ""rj = sjn1 + tjn2 for all j"
Yes, thanks for noticing.
2:28 slip of tongue ("when all inputs are zero")
Yes, you are right. It should be "when all inputs are one" .