Orhan Ergun 1 Comment

Segment Routing Fast Reroute

Segment Routing Fast Reroute  – Traffic Engineering with Segment Routing uses LFA mechanism to provide 50 msec fast reroute capability. Current Segment Routing implementation for the OSPF uses regular LFA (Loop Free Alternate) for fast reroute in Cisco devices.

Because LFA (Loop Free Alternate) has topology limitations, it does not include many faulty scenarios. 

On the other hand, the IS-IS supports topology independent LFA and TI-LFA covers every faulty scenario.

As of today, Segment Routing is enabled on ASR9000 and CRS1/3. Cisco NXOS software supports Segment Routing.

Indeed, you do not need to configure tunnels, complex link, or node protection configuration to use LFA to provide fast reroute capability.

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Orhan Ergun 2 Comments

What is The Real Reason Behind IP and MPLS Traffic Engineering ?

MPLS traffic engineering has many use cases and it helps to solve the problems in an MPLS enabled networks.

These use cases are in general; QoS guarantee, End to End SLA , Fast reroute, Admission control and so on.

All of them at the end is done for the COST SAVING.

The real reason behind MPLS Traffic engineering is cost saving. This is same for the IP Traffic Engineering as well.

Sometimes as a technical people we tend to forget the real reason behind these technologies and push ourselves to make it work on the network although we could find an easier, simpler, flexible, scalable solutions since we don’t focus on the business problem.

In this article I will show you couple alternative ways for the traffic engineering and then explain why you wouldn’t need MPLS Traffic engineering for the link bandwidth utilization.

 

traffic engineering fish problem

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