IS-IS is a link state routing protocol. Commonly used in Service Provider networks.
You need OSPF or IS-IS to distribute link information such as reserved, unreserved and used bandwidth, metric, link colouring information.These informations are used by CSPT ( Constraint based shortest path first ) algorithm.
What makes for a successful protocol ? Which protocol is successful and why ? Have you ever been asked these questions ? As an engineer you cannot say I believe Protocol X is successful or Protocol Y is not.
OSPF Prefix Suppression helps to company to use 200 routers in their network without any problem. You can think that, some companies use more than 200 routers in their OSPF network, why this post is special? You will understand why in 10 minutes.
IS-IS Overload Bit – Why IS-IS Overload bit is used ? What are the use cases ? In this post, I will explain the Overload bit which is an important feature of IS-IS routing protocol.
OSPF and MPLS is most commonly used two technologies in an MPLS VPN environment. In this post I will share a mini design scenario with you and ask couple questions about the fictitious company architecture.
– In the below picture, where should you place an OSPF ABR (Area Border Router) to scale OSPF design ? Why ?
If you design multi level IS-IS network and if you have more than one exit (L1-L2 routers) from the Level 1 domain, you will likely create a suboptimal routing. Multi-level IS-IS design is for large-scale network. What’s more, most of the real life networks use only flat Level 2 IS-IS as their interior gateway protocol …