Description
Classify option code zero as pad, 255 as end, and every other byte as option.
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.
Classify option code zero as pad, 255 as end, and every other byte as option.
When to use this tool
Use DHCP Option Pad End Token when you need to decode or encode one explicit packet field.
How to use the tool and how it works
- Enter code. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read kind, consumesLengthByte. Inspect consumesLengthByte before interpreting the associated values.
Classify option code zero as pad, 255 as end, and every other byte as option. Only ordinary options consume a length byte.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| code | Code | Required. Safe integer; minimum 0; maximum 255. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| kind | Kind | Required. Text; maximum UTF-16 length 8192. |
| consumesLengthByte | Consumes Length Byte | Required. Boolean. |
{
"input": {
"code": 0
},
"output": {
"kind": "pad",
"consumesLengthByte": false
}
}Limitations and assumptions
- The option payload, enclosing message, and sequence termination are not inspected.
- 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
- DHCP Option Length Octet Field
Require a code from 1 through 254 and a length byte from 0 through 255; return the two-byte header.
- TCP Option Nop End Kind Token
Map kind 0 to end-of-option-list and 1 to no-operation; both are single octets.