MPLS network

MPLS – Multi-Protocol Label Switching

MPLS is usually classified as a 2.5 layer protocol because it operates between layers 2 and 3 of the OSI model. When a packet gets in a Provider Edge (PE) router, coming from an IP routed network, it’s then classified into a Forwarding Equivalence Class (FEC) depending on its characteristics to receive a label. Once […]

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BGP features

This post is not finished yet; I will add other features/options. The topics below are alphabetically ordered. BGP Routing Information Base (RIB) First of all, BGP speakers exchange NLRI (Network Layer Reachability Information) that we usually simplify calling it routes or prefixes. NLRI is a set of network address and length tuples:, where 200.0.0 […]

Routing Table Printing

Routing: Metrics and Administrative Distance

When checking a router’s routing table, you will get something like this:

Notice the values between the brackets (Cisco output): they differ. These values are the costs of the routes. The first value is the administrative distance (AD). It indicates the priority of each routing protocol. The second value is the Metric. It is a […]

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My CCNA R&S Studies

Last week (August 2nd, 2017) I tried CCNA exam for the first time; I am not surprised I didn’t pass because I am aware of my weakness in tests, especially in multi-selection ones; some of my past experiences make me believe it. I am pretty sure I have more skills than CCNA requires, my professional […]