route cipher

cryptology

Written by

The Information Architects of Encyclopaedia Britannica

Last updated

July 13, 2026

Quick Summary

A route cipher is a type of transposition cipher used in cryptology. In this method, plaintext letters are written into a grid or matrix in a specific order. The ciphertext is then created by reading the letters out of the matrix following a different, predetermined route. The security of a route cipher relies on keeping the matrix dimensions, starting point, and routes secret. While simple route ciphers offer limited security, combining multiple transpositions can create a more complex and secure encryption. This technique was popular in the early history of cryptology and is still used as a component in modern encryption systems.12

Summary created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

2 Britannica Sources

Ask Britannica AI about this topic

Britannica doesn't have a full article on this topic, so we've curated a list of our relevant coverage.

cryptology
Transposition ciphers
…of transposition ciphers, known as route ciphers, that enjoyed considerable popularity in the early history of cryptology. In general, the elements of the plaintext (usually single letters) are written in a prearranged order (route) into a geometric array (matrix)—typically a rectangle—agreed upon in advance by the transmitter and receiver and…
Read More
…of transposition ciphers, known as route ciphers, that enjoyed considerable popularity in the early history of cryptology. In general, the elements of the plaintext (usually single letters) are written in a prearranged order (route) into a geometric array (matrix)—typically a rectangle—agreed upon in advance by the transmitter and receiver and…
Read More

transposition cipher
…of transposition ciphers, known as route ciphers, that enjoyed considerable popularity in the early history of cryptology. In general, the elements of the plaintext (usually single letters) are written in a prearranged order (route) into a geometric array (matrix)—typically a rectangle—agreed upon in advance by the transmitter and receiver and…
Read More
…of transposition ciphers, known as route ciphers, that enjoyed considerable popularity in the early history of cryptology. In general, the elements of the plaintext (usually single letters) are written in a prearranged order (route) into a geometric array (matrix)—typically a rectangle—agreed upon in advance by the transmitter and receiver and…
Read More