Description
Decode bit zero of firstOctet as groupAddress and bit one as locallyAdministered.
Packet headers encode several meanings in fixed-width fields. Bit positions, network byte order, and reserved values must be distinguished from validation of an entire message.
Decode bit zero of firstOctet as groupAddress and bit one as locallyAdministered.
When to use this tool
Use Network: Ethernet Mac Group Local Bits when you need to decode or encode one explicit packet field.
How to use the tool and how it works
- Enter firstOctet. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read result. Expand result to inspect the returned fields.
Decode bit zero of firstOctet as groupAddress and bit one as locallyAdministered.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| firstOctet | First Octet | Required. Safe integer. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| result | Result | Required. Object. |
| result.groupAddress | Group Address | Calculated result member: boolean. |
| result.locallyAdministered | Locally Administered | Calculated result member: boolean. |
{
"input": {
"firstOctet": 3
},
"output": {
"result": {
"groupAddress": true,
"locallyAdministered": true
}
}
}Limitations and assumptions
- This does not validate a complete MAC address or identify its owner.
- Outputs are nested inside result. Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Inspect the complete captured header and apply the relevant protocol's structural and state rules.
References
Similar or alternative tools
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