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Mastering ServiceNow by Martin Wood

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Finding devices with Shazzam

The vast majority of devices on a corporate network will have an IP address. Even if the device speaks multiple protocols (such as a SAN communicating over Fibre Channel), a management IP is likely to be available. Each IP address should be unique within the network, much like a phone number.

A port scan is much like someone deciding to ring every phone number in a town, one after another. If someone picks up, then the assumption is that the phone number is valid.

However, imagine if all the phones had extensions on them, which were mandatory to use. Then, in addition to knowing what phone number to dial, you would also have to give the extension number when you called it. However, to be helpful, suppose everyone agreed ...

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