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 networ... more
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... more
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 ... more
After years of struggles, the IP fragmentation remains one of the challenges in IP network deployment, particularly if you have to implement extra layers in the protocol stack (like PPP over Ethernet)... more
The five nines (99.999% availability of a service) is the holy grail of many Chief Information Officers (CIO). To reach this goal, the average monthly downtime should be less than 25 seconds, which is... more
A few years ago, the traditional wisdom was that you could not do load balancing in networks using Border Gateway Protocol (BGP) as their core routing protocol. The technology, actually its implementa... more
Selecting the right IP routing protocol is one of the most important decisions in the network design phase. But even after careful consideration of all facts known to you at that time, you might get i... more
The introduction of real-time mission-critical applications (like voice-over-IP) into data networks has prompted many network designers to tune their routing protocols for faster convergence. The resu... more
The February IP Corner article Small Site Multi-Homing described how to implement the small site multi-homing with existing Cisco technologies in the existing ISP environment. That article has generat... more
The cost optimization in the IT industry is affecting all segments of network design and implementation. For example, some IP services like DHCP and DNS, which were previously distributed throughout t... more