Reassemble source fragments
05A source can split a packet with Fragment headers. Reassembly belongs at the destination.
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DIAGRAM§ 4.5 ↗
RFC 8200 · § 4.5EXAMPLE
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03
Reassemble only a valid complete set.
A conflicting overlap causes the packet’s fragments to be discarded.
Protocol participantThreat or exceptionProtocol controlSimplified drawings · precise section references
RFC 2460RFC 8200 § 4.5
RFC 8200 incorporates the rule to abandon overlapping-fragment reassembly and silently discard the fragments; Appendix B records this change.
Read the updated RFC section ↗Routers forward fragments; the destination reconstructs the packet.
- Fragment Identification and offsets associate the pieces; non-final fragment data is aligned to eight-octet units.
- The first fragment must contain all headers through the first upper-layer header.
- Overlapping fragments cause reassembly to be abandoned and received fragments discarded; exact duplicates may be detected and discarded separately.
Fragmentation is discouraged where the application can size packets to the path. Missing pieces can expire without a completed packet.
Read the RFC section ↗Diagrams simplify the RFC. Read the linked sections for complete requirements.
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