Internet Protocol fragmentation and reassembly
E519653
Internet Protocol fragmentation and reassembly is the process by which large IP packets are split into smaller fragments for transmission across networks with limited maximum transmission units and then reassembled back into the original packet at the destination.
Statements (48)
| Predicate | Object |
|---|---|
| instanceOf |
Internet Protocol feature
ⓘ
networking mechanism ⓘ |
| appliesTo |
IPv4
ⓘ
IPv6 ⓘ |
| canCause |
higher processing overhead on routers and hosts
ⓘ
increased packet loss probability when any fragment is lost ⓘ reduced performance for real-time applications ⓘ |
| characterizedBy |
fragmentation occurring in-network for IPv4
ⓘ
fragmentation only at endpoints for IPv6 ⓘ |
| constrainedBy | MTU of each link along the path ⓘ |
| differsBetween | IPv4 and IPv6 fragmentation behavior ⓘ |
| discouragedIn | modern network design ⓘ |
| governedBy |
RFC 791
NERFINISHED
ⓘ
RFC 8200 NERFINISHED ⓘ |
| handledBy | IP layer ⓘ |
| hasPurpose | to allow transmission of packets across links with smaller Maximum Transmission Units ⓘ |
| involves |
reassembling fragments into the original IP packet
ⓘ
splitting a large IP packet into smaller fragments ⓘ |
| mayResultIn |
discarding all fragments if any fragment is missing
ⓘ
discarding all fragments if reassembly timer expires ⓘ |
| mitigatedBy |
Path MTU Discovery to avoid in-path fragmentation
ⓘ
firewall policies that drop suspicious fragments ⓘ |
| partOf | Internet Protocol NERFINISHED ⓘ |
| performedBy |
routers in IPv4
ⓘ
sending host in IPv6 ⓘ |
| reassembledBy | destination host ⓘ |
| relatedTo |
Don’t Fragment bit used by Path MTU Discovery in IPv4
ⓘ
Path MTU Discovery NERFINISHED ⓘ |
| requires |
all IPv6 fragments of a packet to carry the same Fragment Identification value
ⓘ
all fragments of a packet to have the same Identification value ⓘ all fragments of a packet to have the same destination address ⓘ all fragments of a packet to have the same protocol field value ⓘ all fragments of a packet to have the same source address ⓘ reassembly timeout at the destination ⓘ |
| securityConcern |
fragmentation-based evasion of intrusion detection systems
ⓘ
overlapping fragment attacks ⓘ resource exhaustion via many incomplete fragment sets ⓘ |
| transparentTo | transport layer protocols ⓘ |
| uses | IP header length field to compute fragment data boundaries ⓘ |
| usesConcept |
Maximum Transmission Unit
ⓘ
Path MTU ⓘ |
| usesExtensionHeader | IPv6 Fragment header ⓘ |
| usesField |
Flags field in the IP header
ⓘ
Fragment Offset field in the IP header ⓘ Identification field in the IP header ⓘ |
| usesFlag |
Don’t Fragment flag
ⓘ
More Fragments flag ⓘ |
| usesUnit | 8-byte blocks for Fragment Offset ⓘ |
Referenced by (1)
Full triples — surface form annotated when it differs from this entity's canonical label.