The Cisco Packet Tracer is a tool for learning and simulating networks interactively for instructors and students of Cisco CCNA. This e-learning software is offered as part of the Cisco Networking Academy. This tool allows users to create network topologies, configure devices, inject packets, and simulate a network with multiple visual representations. Packet Tracer focuses […]
Don’t depend solely on practice exams for Cisco Certifications
Preparing for a Cisco Certification solely with Practice exams is a method that many candidates follow, however I do not recommend this study method at all. My intention in this article is not to slam practice exams. I just want to address the phenomenon among Cisco certification candidates who use practice exams solely as an […]
TrainSignal Review
The Importance of IT Training Information Technology is a booming industry. For an individual who decided to get into this field, it will be a rewarding decision in terms of salary compensation but also quite a challenge too. Attending a focused and high quality I.T training related to your profession is inevitable if you want […]
Configuring Cisco Router Interfaces
One of the main elements to configure on a Cisco router is its interfaces. The router is usually equipped with Ethernet interfaces (for LAN connectivity) or Serial/ATM/T1/E1 interfaces for WAN connectivity. Below you will find three typical router interface configuration scenarios to get an idea about this important setup. Configuring Ethernet or Fast Ethernet Interfaces […]
GNS3 Graphical Network Simulator
GNS3 is a graphical network simulator that allows simulation of complex networks. To allow complete simulations, GNS3 is strongly linked with : * Dynamips, the core program that allows Cisco IOS emulation. * Dynagen, a text-based front-end for Dynamips. * Qemu, a generic and open source machine emulator and virtualizer. GNS3 is an excellent complementary […]
Cisco ASA 5500 Firewall Configuration-User Interface and Access Modes
This article describes the user interface and access modes and commands associated with the operation of Cisco ASA 5500 firewall appliances. We assume that you know how to connect to the appliance using a console cable (the blue flat cable with RJ-45 on one end, and DB-9 Serial on the other end) and a Terminal […]
Using TCP Intercept to mitigate DoS SYN Attacks
The most common attack against Service Provider IP Networks is Denial of Service. Usually these attacks take the form of “Many-to-One Attacks” where multiple attacking sources send flooding traffic towards a single destination. These attacks are sometimes called Distributed Denial of Service. Usually the attacking hosts are “zombie” computers which are compromised by hackers and […]
IEEE 802.3ba Standard -100 Gbps Ethernet is Here
On June 17th, the IEEE has ratified the 802.3ba standard for Ethernet connections with speeds of 40 and 100 Gbps. Both Cisco and Juniper have been supplying high performance network equipment which support the above standard. Cisco for example supports the 100Gbps Ethernet card on its CRS-3 router, while Juniper supports its 100Gbps PIC card […]
A brief overview of CCNA Certification
Do you want to learn how to install, configure and maintain computer networks? Are you looking to develop your professional skills in networking and to demonstrate your expertise or enhance your credibility? Then a Cisco Certified Network Associate (CCNA) certification is an excellent choice for you as an entry level professional. The knowledge that you […]
Cisco ASA Firewall in Transparent Layer2 Mode
Traditionally, a network firewall is a routed hop that acts as a default gateway for hosts that connect to one of its screened subnets. A transparent firewall (or Layer 2 firewall), on the other hand, acts like a “stealth firewall” and is not seen as a Layer 3 hop to connected devices. The appliance connects […]
Cisco Vs Juniper
I have found the following article at pcworld.com and thought about sharing with you. Its a good overall comparison between Cisco and Juniper, the two biggest players in the networking arena. It’s been an ongoing debate for much of the last 14 years – Cisco or Juniper? Increasingly, that argument will hinge on which router […]
Configuring IPS Protection and IP Spoofing on Cisco ASA 5500 Firewalls
The Cisco ASA firewall appliance provides great security protection out-of-the box with its default configuration. However, to increase the security protection even further, there are several configuration enhancements that can be used to implement additional security features. Two of these features are IP Spoofing protection and basic Intrusion Prevention (IPS) support. IP Spoofing Protection IP […]
IPv4 addresses are running out
It is beyond discussion that the full implementation of IPv6 in all Internet services and infrastructures will take place sooner or later. However, a harsh reality has knocked our door a few months ago. The Number Resource Organization (NRO) has warned that the available free IPV4 address space has fallen below 10%, which is considered […]