Description
Inspect the multicast and locally administered bits of a supplied MAC/EUI first octet.
Identifier validation can involve several distinct questions: whether text has the expected shape, whether a checksum is consistent, and whether an authority actually assigned the identifier. Formatting and field extraction address narrower questions. Each result must be read according to the particular property the tool checks.
Inspect the multicast and locally administered bits of a supplied MAC/EUI first octet.
When to use this tool
Use Mac Eui Local Multicast Bit Check when you need the particular shape, formatting, field, or checksum property as one explicit stage in an identifier workflow.
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 multicast, locallyAdministered. Inspect multicast, locallyAdministered before interpreting the associated values.
Require firstOctet from zero through 255. Return multicast from bit zero and locallyAdministered from bit one of that octet.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| firstOctet | First Octet | Required. Safe integer; minimum 0; maximum 255. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| multicast | Multicast | Required. Boolean. |
| locallyAdministered | Locally Administered | Required. Boolean. |
{
"input": {
"firstOctet": 3
},
"output": {
"multicast": true,
"locallyAdministered": true
}
}Limitations and assumptions
- Both flags can be true. The input is an already extracted first octet, not a full MAC/EUI address, and the tool does not verify allocation, device identity, uniqueness, or network behavior.
- The field tables state structural bounds; the mechanics also specify cross-field constraints. Malformed inputs and unsupported domains cause errors. A successful false flag, empty branch value, or zero placeholder has the meaning stated above and is distinct from an input error.
Alternative or Complementary methods
Use a complete format and checksum validator when required, then consult the issuing registry or verification process for assignment and identity. Preserve meaningful leading zeros as text.
References
Similar or alternative tools
- Uuid Variant Bit Pattern Check
Classify an integer octet from zero through 255 by leading bits: below 128 as ncs, below 192 as rfc, below 224 as microsoft, and the remainder as future.
- Ark Qualifier Leading Separator Check
Return valid when qualifier is empty or starts with slash or dot.