In order to perform estimations of a traffic model for multimedia flows, it is necessary for the researcher to have precise control of the test environment, minimizing errors and interference that may occur, leaving a test scenario that allows a smooth development to the application to be modeled. As an example, we have selected a VoIP traffic which is quite easy to interpret and it provides some of the things that must be done.   Scenario for testing Figure # 1 shows the diagram used for testing in order to obtain the pattern of traffic on the transmission of voice…

Some time ago, I read an interesting article of a "successful attack" against AES, the famous symmetric-key algorithm. Raphael C.-W. Phan [1] presented a seven rounds "impossible differential attack" for AES-192 and AES-256. Someone may ask: what kind of attack is this?, well, it is a crypt-analysis that takes advantage of the differences that are impossible to be, in a data block through encryption, in order to discover the key?. Without going into many details of the method used, below I comment some of the most important results of this study. The attack involves taking pairs of identical texts in…

I present you my favorite applications to capture packets on the network, although they are well known for their features, I decided to give a little space to discuss some of their features. In addition to data capture, these applications are useful for certain packets analysis with the obtained data, on the other hand, when the analysis that we need to do is a bit complex or very specific, it is always advisable to build our own scripts, but there is no doubt that no matter for what we use them, this applications will help us to obtain useful network…

For some time I have been using various traffic generators, and today I want to share 3 of the that I most use for their interesting features. The traffic generators are useful for injecting traffic of certain applications or network services and not have the need to run such applications, in my case I used to generate the traffic of VoIP, video streaming, video surveillance, and even to make some reverse engineering on certain commercial devices. Then I leave a short review of each of them: