ISP (Internet Service Provider)

An Internet Service Provider sells internet access to residential, business, or wholesale customers. Telecom carriers are typically also ISPs, often the dominant ones in their market. ISP-specific security responsibilities include anti-spoofing (BCP 38), abuse handling, DDoS mitigation upstream of customers, and DNS hygiene.

Categories: Threats and AttacksInternet and Routing

ISP in context

Telecom threats range from opportunistic SMS phishing and SIM swap to nation-state grade location tracking. The common thread is that most attacks exploit the inherited trust model of legacy signaling protocols.

Telecom networks depend on Internet-style routing (BGP, DNS, MPLS) for interconnect. Route hijacks and DNS abuse can degrade or intercept signaling, which is why RPKI and DNSSEC are now standard hardening for carrier networks.

To place ISP in the wider telecom-security picture, review A5/2, ASN, BGP, BGP Hijacking, CGNAT and CVE — each entry cross-references back to this page so you can walk the topic in either direction.

Related terms

More from the TelcoSec Glossary

Browse the full TelcoSec Glossary, the Ultimate Guide to Mobile Network Security, or the P1 Arsenal of telecom-security tools.