Understanding IPSec Protocol

VPN is a virual private network which creates a secure tunnel over a public network. It can be – client to firewall, – router to router, – firewall to firewall. VPN uses the internet as the public backbone to access a secure private network. For example, remote employees can access their office network VPN Protocols can […] Read more»

Setting up PPTP VPN in Ubuntu 14.04

I installed vpn application as, [crayon-5ab2d96dedb04161898151/] Then, i defined server ip and client ip range in /etc/pptpd.conf as, [crayon-5ab2d96dedb12049066244/] Then, i define DNS server for pptp clients in /etc/ppp/pptpd-options as, [crayon-5ab2d96dedb16879308767/] After that, i defined vpn users in /etc/ppp/chap-secrets as, [crayon-5ab2d96dedb19768106244/] Then, i setup ip forwarding and define rules in iptables as, [crayon-5ab2d96dedb1d363011357/]   That’s it. Cheers!! Read more»


Kannel SMS Gateway setting up

  Kannel is an open source WAP and SMS gateway works as both an SMS gateway, for implementing keyword based services via GSM text messages, and a WAP gateway, via UDP.   The kannel mainly consist of: 1. Core – Bearerbox 2. SMSbox 3. WAPbox Kannel can be installed by compiling directly from source code […] Read more»


Mariadb Galera Cluster setting up

Mariadb is drop in replacement for MySQL which was developed just after MySQL acquired by Oracle. Both Maria and My are named after daughter of its database developer. Clustering in Mariadb is very easy and straightforward. Currently, there are two releases of Mariadb, 5.5 which is stable version and 10.0 is development version. I installed the […] Read more»


circle of fifth

This is how i learn ” Father Christmas Gave Dad An Electric Bed”. So, in the above circle every chord is at distance of fifth like C D E F G, here G is at fifth distance from C and so on. The above circle of fifth also helps to find the key signature (also […] Read more»


Encryption operation is done by substitution, transposition and product. For a system to be computationally secure,  the cost of breaking the cipher exceeds the value of the encrypted information and the time required to break the cipher exceeds the useful lifetime of the information. Symmetric Encryption: Mathematically, Y = Ek(X) Encryption Model, X = Dk(Y) […] Read more»


Network Security Services

Security services as per ITU-T X.800 are authentication, access control, data confidentiality, data integrity and non-repudiation. Security attacks can be categorized as interruption (attack on availability), interception (attack on confidentiality), modification (attack on integrity) and fabrication (attack on authenticity). Malicious programs like virus, worm, zombie are replication on behavior and  trapdoors, trojan horse are non […] Read more»


Network Security: An Introduction

Network Security is very essential in any organization. Without network security, there is always threat in that organization for information being hacked and cracked. Network security is the protection of information and systems and hardware that use, store and transmit that information, as defined by National Telecommunications Security and Information System Security Committee. So, network […] Read more»