Archive for the ‘IP Corner Technical Articles’ Category
November 4th, 2008 by Marjan Bradesko
In today`s Voice over IP (VoIP) environment the final measure of network performance is provided by its users. A convergence of the network after the node failure in a traditional routing environment is simply too slow for voice users. Several attempts, mainly proprietary, have been introduced so far to speed ...
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October 1st, 2008 by Marjan Bradesko
Crypto maps - used as one of the oldest Cisco IOS implementation options for IPsec – have a downside - they do not provide for a routable logical interface. When migrating from a traditional WAN or upgrading an existing WAN to use cryptography, it may be beneficial to reuse the ...
Posted in IP Corner Technical Articles, IPsec, VPN | No Comments »
September 1st, 2008 by Mojca Parkelj
The April IP Corner article It’s good to be on time describes how you can use Network Time Protocol (NTP) to synchronize the real-time clock of your network devices with external time references. As soon as you start relying on your routers having pretty exact time, NTP becomes part of ...
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August 1st, 2008 by Mojca Parkelj
When designing a network solution, we often are faced with a myriad of parameters that influence the design process and the selection of the final solution. A network designer ideally would want to control as many parameters as possible apart from the business requirements, which is the basic set of ...
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July 1st, 2008 by Mojca Parkelj
Default routing should be a simple concept, but becomes surprisingly complex in routing protocols that have multiple layers of default routes. In this IP Corner article, Ivan Pepelnjak, the Chief Technology Officer (CTO) at NIL Data Communications, describes how the Open Shortest Path First (OSPF) protocol uses default routes and ...
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June 1st, 2008 by Bojana Stucin
If you want to deploy high-availability public servers within your network, you should implement proper multi-homing solution including BGP routing with the Service Providers. But even if you use alternative solutions, like the ones presented in the previous IP corner article Small Site Multi-Homing, there are ways to deploy public ...
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May 1st, 2008 by Bojana Stucin
Network designers and implementers try to avoid policy routing, as its common implementation in Cisco IOS requires a complex mix of access-lists and route-maps that have to be deployed on a hop-by-hop basis. In most cases, distance vector routing protocols can be used to implement policy routing requirements in large ...
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April 1st, 2008 by Bojana Stucin
The importance of having accurate time on distributed servers and even personal workstations has been recognized long time ago by the IT managers, but it hasn’t been applied consistently to the networking devices. In this IP Corner article, Ivan Pepelnjak, the Chief Technology Officer (CTO) at NIL Data Communications, describes ...
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March 1st, 2008 by Bojana Stucin
Border Gateway Protocol (BGP) was always considered a mastodonic routing protocol: huge, complex, hard to understand and configure, and very slow to converge. When Cisco decided to use it to implement layer-3 Virtual Private Networks (VPNs) due to its enormous route carrying capabilities, the slow convergence of BGP became a ...
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February 1st, 2008 by Bojana Stucin
Contrary to common wisdom, OSPF is not a pure link-state protocol. It uses link state algorithms within an area, but behaves almost like a distance vector protocol between the areas. This distinction introduces temporary routing instabilities into multi-area OSPF network that does not use inter-area summarization. In today's IP Corner ...
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