OSPF LSA Types
OSPF is a commonly used IGP used in a wide range of enterprise environments. It uses its algorithm to determine the shortest path to the destination network address. This algorithm is based on the...
OSPF Virtual Links
In an OSPF network, usually all areas need to be connected to the backbone area, area 0. There is a way around this though. Take a look at the topology above. Area 0 is...
3 ways to NAT on a Cisco Router
When working with Cisco routers, whether in a lab or production environment, there are may ways that NAT will come into play. This article will discuss the three most common reasons you would need...
Troubleshooting Basic BGP Path Issues
In everything I've been working on lately, a lot of it has revolved around BGP. Most of this has come from my CCIE studies. In practice labs and scenarios something I've become accustomed to...
When to Use BGP Next-Hop-Self
When beginning their CCIE studies, some people, including myself, wonder exactly when the next-hop-self option of BGP should be used. For this example we will use the topology above. Routers 1 and 2 have...
EIGRP and AF-Interface
Within the realm of EIGRP, there are two different modes, classic and named. Classic is the usual version most people are used to where the protocol configuration starts with "router eigrp 123" or something...
Two Methods of MPLS Interface Configuration within OSPF
Within all of the practice labs I have worked through for the CCIE Lab exam and in most real world applications I have seen, MPLS networks are run on top of (or within) an...