Blog

  • What is a Light Virtual Access Point (LVAP)?

    Home Aug 26, 2020 | 18:16 pm

    What is a Light Virtual Access Point (LVAP)? Wireless networks are widely used in areas such as business centres, airports, university campuses or even in many city areas. For this scenarios there are solutions for coordinating Wi-Fi access points, usually known as Enterprise Wi-Fi. Although commercial solutions exist, these are proprietary, closed and costly, which in most of the cases make them infeasible for many organizations.In this context, there are some proposals for inter access points coordination solutions enabling advanced features such as load balancing, frequency planning or power control. Some works have proposed the adaptation of certain abstractions and concepts from Software Defined Networks (SDNs), for its[…]

    Read more...
  • General architecture for Software Defined Networking (SDN)

    Home Aug 23, 2020 | 13:57 pm

    General architecture for Software Defined Networking (SDN) La terminología y arquitectura de capas para los sistemas SDN ha sido definida por el Software-Defined Networking Research Group (SDNRG) del Internet Research Task Force (IRTF) en [1]. Aunque no tiene como objetivo estandarizar ninguna capa o interfaz, proporciona una referencia de los enfoques que se pueden seguir al definir arquitecturas SDN. La Open Networking Foundation (ONF) propuso una arquitectura diferente en [2], que está más orientada a servicios, mientras que la propuesta por el IRTF tiene una visión más funcional [3].La Figura 1 describe la arquitectura propuesta por el IRTF que consta de:Application Plane: en ésta capa es donde[…]

    Read more...
  • How to setup a Kubernetes cluster

    Home Aug 1, 2018 | 14:06 pm

    How to setup a Kubernetes cluster The initial setup consists of a remote server running KVM in which three virtual machines were installed using Ubuntu 16.04. Each virtual machine has one network interface bridged to a physical network interface on the remote server, so that each VM is using a different interface of the server and IP addresses were assigned accordingly. At the end of this tutorial, you will have a kubernetes cluster that consist of one Kubernetes master and two Kubernetes nodes. Docker installation First, let's install updates, dependencies and docker:sudo apt updatesudo apt upgradesudo apt install apt-transport-https # already installedsudo apt install docker.io Now,[…]

    Read more...
  • Kerberos protocol operation

    Home Sep 8, 2014 | 22:00 pm

    Kerberos protocol operation The authentication protocol Kerberos allows a number of computers to prove their identity among them safely over an insecure network. The operation of the protocol is based on the Needham-Schroeder protocol, which defines a ''trusted third party'' called Key Distribution Center (KDC). William Stallings in his book Fundamentals of Network Security: Applications and Standards, Second Edition (p.394) defines a KDC as follows: Authorized system to transmit temporary session key for users. Each session key is transmitted encrypted using a master key that the Key Distribution Center shares with the target user. The KDC can be seen as a set of[…]

    Read more...
  • How to modify files with SED?

    Home May 12, 2014 | 05:00 am

    How to modify files with SED? What is sed? Sed is a stream editor which is used to perform basic text transformations on an input stream (a file or input from a pipeline) or filter strings. It permits to modify the contents of different lines in a file, based on some parameters. For the examples shown in this article, you used the 4.2.1 version of sed as shown below:sed --versionGNU sed version 4.2.1Copyright (C) 2009 Free Software Foundation, Inc.This is free software; see the source for copying conditions. There is NOwarranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE,to the extent permitted by law.[…]

    Read more...