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So i know the gist of it. Thanks to the help here

Network Address i see as anything ending with 0 Example: 192.168.0.0

Broadcast Address i see as anything ending with 255 Example: 192.168.0.255

Whereas NetID i honestly just see in theory as what your network is identified as, example 192.168.0.X

But let me know if i am wrong. Just curious?

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    Network addresses most certainly don't have to end with .0 and not every address ending with .0 is a network address. The same goes for broadcast addresses on 255. Please see the answers to this question for a much more detailed explanation.
    – Teun Vink
    Commented Feb 16 at 12:49
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    Your assumptions are too simple and often not correct. See here for a discussion on how IP addresses, subnetting, masks and prefixes work.
    – Zac67 ♦
    Commented Feb 16 at 13:09
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    "all-zeros" and "all-ones" addresses. Networks do not always land perfectly on /8, /16, and /24 boundaries. (and haven't had to for many DECADES.)
    – Ricky
    Commented Feb 16 at 15:35

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Your "gist" is wrong, unfortunately. "0"s and "255"s may or may not indicate anything.

The important thing to remember is that IP addresses are 32-bit binary numbers. The dotted-decimal notation (1.2.3.4) is just there to make it easier for humans to read. The dots have no meaning.

So the network address depends on the subnet mask. You can't assume it ends in zero. Same for the broadcast address -- it depends on the subnet mask.

The term Netid is not well-defined. We would have to see the term in context to tell you for sure if is the same thing as network address.

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To answer the titular question... "Network Address" is a well defined term. (in many RFC's) NetID is not.

The Network Address is the all-zeros address of a subnet. For a /24, that's a dot-zero. For a /25 [0xxxxxxx & 1xxxxxxx], that's a dot-zero and dot-128. Broadcast is the all-ones address. (127 and 255 for the aforementioned /25)

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Network Address i see as anything ending with 0 Example: 192.168.0.0

Not correct. A network address or prefix is anything where the host bits are all 0. Your example works for /24 only.

With e.g. a /26 subnet, the network address could end with .0, .64, .128, or .192.

A /23 could end with any even number in the third octet and 0 in the fourth.

Broadcast Address i see as anything ending with 255 Example: 192.168.0.255

The subnet directed broadcast address is the network address with all host bits 1. Same logic as above applies (.255 only for a /24, /26 with .63, .127, .191, .255, and so on).

In a nutshell: without knowing the subnet mask, you can't tell whether an address is a prefix or a directed broadcast. E.g. 192.168.0.255 is not the broadcast address for 192.168.0.0/23.

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