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MPLS

Segment Routing (SR-MPLS): Replacing LDP and RSVP-TE

SR-MPLS keeps the MPLS data plane and drops LDP and RSVP-TE. Prefix-SIDs, adjacency-SIDs, source-routed label stacks, SR-MPLS vs SRv6, and why networks migrate.

Jun 19, 2026 4 min read

VLAN

VTP (VLAN Trunking Protocol): v1, v2, v3 and Why It's Dangerous

How VTP propagates VLANs across a domain, the three modes, the revision-number disaster, v1/v2/v3 differences, and why many engineers disable it.

Jun 17, 2026 5 min read

OSPF

OSPF Passive Interface: What It Does and Where to Use It

OSPF passive-interface stops Hellos and adjacencies on an interface but still advertises its subnet. Config, the default pattern, and the route-filter gotcha.

Jun 15, 2026 4 min read

Learn networking by building it

Blog

Segment Routing (SR-MPLS): Replacing LDP and RSVP-TE

VTP (VLAN Trunking Protocol): v1, v2, v3 and Why It's Dangerous

OSPF Passive Interface: What It Does and Where to Use It

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