Understanding BGP Link State (BGP-LS)

????What is BGP-LS?

BGP-LS (BGP Link-State)is anextension of BGPthat allows routers to exchangenetwork topology informationviaLink-State NLRI.

HelpsSDN controllers and path computation elements (PCEs)makeintelligent routing decisions.

????What Does BGP-LS Advertise?

✅Node Information– Router IDs, Loopbacks

✅Link Information– Bandwidth, Delay, Cost

✅Prefix Information– Network Subnets

✅Topology Information– Full network graph

Why is the Answer TRUE?

✅BGP-LS introduces a new NLRI formatfor advertising link-state information.

✅NLRI (Network Layer Reachability Information) is used to distribute topology datato SDN controllers.

✅It improves path optimization by enabling centralized traffic engineering decisions.

Real-World Application:

SDN-Based Traffic Engineering:Used inSegment Routing (SR)networks for centralizedpath selection.

MPLS TE (Traffic Engineering):Optimizes network paths dynamically based onreal-time link-state data.

✅Reference:Huawei HCIE-Datacom Guide – BGP Link-State (BGP-LS) Fundamentals