Three words, three separate claims. Dedicated means the address is assigned to you and nobody else for as long as you pay for it — it does not rotate and it is not in a shared pool. ISP means the address block is registered at a regional registry to a consumer broadband carrier rather than to a hosting company. And in practice it also means hosted in a datacentre: the machine sits on real server hardware with a real uplink, it is just wearing a carrier registration.
That combination is why the term exists. A rotating residential proxy borrows real home connections, which makes it hard to detect but also slow, unpredictable, and shared with whoever else is using that pool. A plain datacentre server is fast and stable but registered to a hosting company, which is the first thing a fraud system looks at. A dedicated ISP address gives you the registration of the first and the behaviour of the second.
It is also why it costs what it costs. Carriers do not hand out address blocks the way registries hand them to hosting companies, so supply is genuinely limited — and the specs you get for the money will look poor next to a normal VPS. One core and a gigabyte of RAM for the price of a small dedicated server is normal here. You are paying for the registration, not the hardware. If the specs look generous for the price, check the address before you believe the label.
Verify two things and you have checked almost everything that matters. First, which autonomous system announces the address — it should belong to a carrier you can name. Be sceptical of organisation names containing "fiber" or "broadband" that match no carrier you have heard of; that pattern is common among resellers. Second, whether the registration country matches where the server actually is — registered in the US but locating to Hong Kong means the address is being broadcast, and platforms treat that mismatch as an anomaly. Ask for a test IP before you pay, and use the refund window.
LisaHost