LOKI
block ciphers
In cryptography, LOKI89 and LOKI91 are symmetric-key block ciphers designed as possible replacements for the Data Encryption Standard (DES). The ciphers were developed based on a body of work analysing DES, and are very similar to DES in structure. The LOKI algorithms were named for Loki, the god of mischief in Norse mythology.
LOKI89
LOKI89 was first published in 1990, then named just "LOKI", by Australian cryptographers Lawrie Brown, Josef Pieprzyk, and Jennifer Seberry. LOKI89 was submitted to the European RIPE project for evaluation, but was not selected.
The cipher uses a 64-bit block and a 64-bit key. Like DES, it is a 16-round Feistel cipher and has a similar general structure, but differs in the choice of the particular S-boxes, the "P-permutation", and the "Expansion permutation". The S-boxes use the non-linearity criteria
developed by Josef Pieprzyk, making them as "complex" and
"unpredictable" as possible. Their effectiveness was compared
against the known design criteria for the DES S-boxes. The
permutations were designed to "mix" the outputs of the S-boxes
as quickly as possible, promoting the avalanche and completeness
properties, essential for a good Feistel cipher.
The public source identifies “LOKI” as block ciphers. This brief keeps that definition visible, then builds a research path around LOKI, block and ciphers.
Why this record matters
A short description can identify a subject without explaining its stakes. For “LOKI”, the useful work is to connect “block ciphers” to the records capable of establishing context and consequence.
Named sources, stable identifiers and responsible institutions provide the strongest route from overview to verifiable evidence. The source revision retrieved here is dated Mar 2, 2026. The linked authority identifier is Q378566. None of the 1 selected statements returned an explicit reference. The first chronological checks are 1990.
Overview language is designed for orientation and should not be treated as a substitute for the evidence cited beneath it. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.
- Subject orientation
- Search vocabulary
- Locating named sources
The closest primary source, responsible institution and strongest cited specialist reference.
Three-step research path
- Establish the record: confirm the title “LOKI”, its source revision and the description used here.
- Expand the search: follow LOKI primary sources, LOKI archive and LOKI research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “LOKI”?
- Which cited source is closest to the event, object or claim?
- Which institution is responsible for the underlying evidence?
Search terms from this dossier
This entry incorporates text from “LOKI” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.