Currently viewing the tag: "Routing and Switching"

Cisco: Simple configuration of IP multicast dense mode

By On December 15, 2008 · 5 Comments

Until now, I did not meet a network engineer to be really “in love” with multicast. Some are considering challenging, interesting, useful but most of the network engineers (I repeat myself, from the persons that I discussed with) are rather preferring do other topics that multicast. If you are curious about my position in regarding [...]

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Cisco: BGP path selection for inbound traffic

By On December 10, 2008 · 3 Comments

In some previous post we saw how we can manipulate BGP paths using attributes for outgoing traffic. Today we will see how to use another BGP attribute, but this time for manipulating inbound traffic. First I would like to ask you to have a look into the topology file and [...]

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Cisco: Traffic manipulation with Policy Based Routing

By On December 5, 2008 · 3 Comments

Cisco Policy Based Routing provides a flexible mechanism for network administrators to customize the operation of the routing table and the flow of traffic within their networks. Policy Based Routing (PBR) offers many advanced features, including selection and forwarding of traffic to discreet Virtual Routing and Forwarding (VRF) instances, as well as Enhanced Tracking of [...]

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Cisco: Very simple NTP configuration

By On December 3, 2008 · 2 Comments

NTP (Network Time Protocol) is usually very simple to configure on Cisco devices. Of course you can reach complex configuration, but since I work in this field I didn’t saw somebody to push the things to extreme in NTP configuration.

NTP is based on server – client relation. It is recommended that in a Cisco [...]

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Cisco: How to improve BGP table stability with route dampening

By On December 3, 2008 · 5 Comments

One of the issues that can affect BGP table stability is link flapping. Imagine that if a link to a network is flapping very often, BGP process has to remove the route to that network from the BGP table and implicit from the routing table and then we the link is available again to re-introduce [...]

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Cisco: BGP path selection for outgoing traffic

By On December 1, 2008 · 2 Comments

Before going further on, please download the topology and the initial configuration files and have a close look into them (mostly into topology drawing). Also, this tutorial is addressed to people that know what is BGP and how to do a basic configuration for peering establishing.

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Cisco: Packet sniffing

By On November 26, 2008 · Leave a Comment

The official term of Cisco for Packet sniffing is  SPAN ( Switched Port Analyzer ) also called sometimes port mirroring or port monitoring and it’s purpose is to select traffic from a source and send to a destination with a network analyzer tool. You can find out there terms like RSPAN, PSPAN, VSPAN, ESPAN, but [...]

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Cisco: SSH enable | disable | reconfigure tutorial

By On November 25, 2008 · 4 Comments

One of the most used method for remote access today is SSH protocol. Even most on the network engineer say what is so complicated in the process of the enable , disable , reconfigure of the SSH process, my experience proved me that it can be really complicated, if you mess up stuff there.

One [...]

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Cisco: Spoof detection

By On November 24, 2008 · 2 Comments

Spoofing is a kind of network attack to compromise your network security with the intention of traffic capture which will enable an attacker to get access to confidential data. Usually a spoof attach is associated with IP spoofing, which means that the source IP of the packet which arrive to your device has been changed [...]

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