OSPFv2
OSPF is the interior routing protocol of choice for enterprise and carrier networks. Understanding area design, LSA types, and SPF convergence is essential for data center networking, WAN design, and network certification paths.
What It Defines
Open Shortest Path First v2 is the dominant link-state IGP for IPv4 interior routing. Routers flood LSAs (Link State Advertisements) to build a complete topology map and compute shortest paths via Dijkstra's SPF algorithm. Defines area architecture (backbone area 0, standard/stub/NSSA), DR/BDR election, route summarization, and external route injection.
Canonical (Normative)
The canonical publication point for finalized RFCs. If a protocol is standardized as an RFC, the RFC Editor text is the normative final reference. Published by the IETF, IRTF, IAB, and independent stream.
Related Specs
BGP stitches the internet together — every AS, CDN, cloud provider, and multi-homed network runs it. Understanding AS path, communities, and prefix aggregation is essential for cloud networking, CDN design, and any serious network engineering role.
IS-IS is the IGP of choice in most Tier-1 and Tier-2 carrier networks and large-scale DC fabrics (Meta, Amazon). It runs under BGP in many hyperscale designs. Essential for service provider and large-scale DC networking roles.
MPLS is the forwarding substrate of carrier networks, MPLS VPNs, and traditional WAN services. Understanding FEC, LDP, and LSP concepts is essential for service provider or enterprise WAN networking.
BFD is how networks achieve sub-second failover — without it, BGP takes 90+ seconds to detect a peer failure. Any high-availability design (active-active DC, SD-WAN, carrier) relies on BFD for fast convergence.