Yup, residential broadband accounts are usually "dynamic"...you often get a new IP address each time you reboot your broadband router. More often with phone company (DSL) types of broadband, as cable broadband typically has longer DHCP lease times.
When you get a "business" broadband account, you usually have options such as getting assigned a "static IP"...so it doesn't change. Typically comes with a higher cost...but usually many other benefits with a business account versus residential.
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