In the market of networking devices, you can find both wireless routers (just like the WiFi devices we have in our homes) and wired routers which can be great performers in both small home networks and in business environments as well. In this article I have researched some great wired router models for both home […]
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Usually, commercial and enterprise grade network routers (such as Cisco, Juniper, HPE etc) run on their own proprietary operating system (OS) software which runs only on the specific vendor’s hardware devices. However, the Open Source community has developed some great Router OS software that can power commodity hardware such as x86 computers or regular SOHO […]
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The purpose of HSRP (Hot Standby Routing Protocol) is to check interfaces and other connectivity parameters, and if the interface is down then a failover takes place from Active HSRP Router to standby HSRP router. There is no direct correlation between HSRP and IPSEC. However, we can use HSRP to provide VPN tunnel failover, as […]
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In our day to day work as network administrators it is often necessary to compare configuration files of Cisco routers, switches, firewalls etc. As we know, a characteristic of Cisco IOS is that the configuration files are stored in text format, but still a line by line comparison of different config files is tedious and […]
[Continue reading]The following article describes the proper way to allow BGP sessions between two routers to pass through a Cisco ASA firewall appliance. Especially if the BGP configuration between the two routers uses MD5 authentication (which is a good security practice), you need some special “treatment” on this session in order to pass it successfully through […]
[Continue reading]With the new modular policy framework (MPF) introduced in ASA versions 7.x and 8.x, the firewall administrator is now able to apply policing and rate limiting to traffic passing through the ASA appliance. I got a few questions from people how this functionality works and decided to throw in a quick example below which you […]
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Device virtualization is one of the most popular topics in IT industry today and Cisco has been supporting this concept in the majority of its network devices. In this article we will talk about Cisco ASA virtualization, which means multiple virtual firewalls on the same physical ASA chassis. Virtual ASA is also known as “Security […]
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This article describes the security levels concept as used in the Cisco ASA firewall appliance. The following information applies to both the older 5500 series and the newer 5500-X series of appliances. What is Security Level A Security Level is assigned to interfaces (either physical or logical sub-interfaces) and it is basically a number from […]
[Continue reading]There are several configuration features on Cisco ASA that require some sort of password or secret-key that you need to enter. Some examples include: VPN pre-shared keys (either for site-to-site IPSEC VPN or for Remote Access). AAA server secret key when communicating with a RADIUS server. Routing Protocols keys (for OSPF, EIGRP). Secret key for […]
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As network engineers, having insights about how our network performs can save us from a lot of headaches. That’s where software tools for network diagnostics are useful for every networking professional. Pingplotter is a network diagnostic software utility used to monitor packet loss, latency, jitter etc in data packets along network paths. This tool lets […]
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One of the most asked questions from those who deployed Cisco Unified Communications Manager is how to provide external caller ID on IP phone display. CUCM does it well for internal phone lines, but what about external incoming calls? Your account managers would love seeing the name of the client calling on the IP phone. […]
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Cacti is a popular open source networking tool that is web based, and it is used both for network monitoring and graphing. In my work environment we use Cacti extensively to mainly monitor bandwidth on interfaces of switches etc. It is a complex tool to learn but very powerful. With Cacti you can poll services, […]
[Continue reading]Learning to configure your Cisco devices from the Command Line Interface (CLI) is an essential step towards your Cisco networking career. This means that you need to learn how to configure the Cisco IOS operating system which runs on routers, switches and other network devices. Acquiring this hands-on experience with the Cisco IOS CLI will […]
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