What is BCP38 and why it is important?

Anurag Bhatia
BCP38 - also known as “Network Ingress Filtering” is concept where we filter incoming packets from end customers and allow packets ONLY from IP’s assigned to them. Before going to BCP38, let’s first understand how packets forwarding work: Here User 1 is connected to User 2 via a series of router R1, R2 and R3. Here R1 and R3 are ISP’s edge routers while R2 is a core router. In typical way the network is setup, entire effort is given on logic of routing table i.