Description
Return forwardable when hopLimit exceeds one.
A wire-format length may count headers, payload, padding, or only part of an enclosing message. Offsets and exclusive ends must use a clearly stated byte convention.
Return forwardable when hopLimit exceeds one.
When to use this tool
Use Network: IPv6 Hop Limit Expired Flag when you need a field-level byte count or boundary check.
How to use the tool and how it works
- Enter hopLimit, action. 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.
Return forwardable when hopLimit exceeds one. For action forward, decrement with a zero floor and set expiredForForwarding at zero or one; for receive, retain the input and leave that expiry flag false.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| hopLimit | Hop Limit | Required. Safe integer. |
| action | Action | Required. Text; one of "receive", "forward". Implementation limit: 8192 Unicode code points and 16384 UTF-16 code units. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| result | Result | Required. Object. |
| result.forwardable | Forwardable | Calculated result member: boolean. |
| result.nextHopLimit | Next Hop Limit | Calculated result member: number. |
| result.expiredForForwarding | Expired For Forwarding | Calculated result member: boolean. |
{
"input": {
"hopLimit": 1,
"action": "forward"
},
"output": {
"result": {
"forwardable": false,
"nextHopLimit": 0,
"expiredForForwarding": true
}
}
}Limitations and assumptions
- Forwardable reports the numeric threshold even for receive; local-delivery policy is not evaluated.
- 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
Compare the computed span with the actual captured buffer and validate its contents separately.
References
Similar or alternative tools
- IPv6 Hoplimit Decrement Expiry Flag
Decrease hopLimit by one with a floor of zero and set expired when the original value is zero or one.
- IPv6 Routing Segments Left Decrement Budget
Decrease segmentsLeft by one with a floor of zero.