Mūlabhadra (മൂലഭദ്ര) aka Mūlabhadri ( :ml:മൂലഭദ്രി) was a secret method of communication employed by the royal spies of the erstwhile Travancore Kingdom during the medieval period. The scheme was also colloquially referred to as Mūlapatra. It was essentially a cryptographic scheme involving a partial transposition of the letters of the

Malayalam Malayalam (; , ) is a Dravidian languages, Dravidian language spoken in the Indian state of Kerala and the union territories of Lakshadweep and Puducherry (union territory), Puducherry (Mahé district) by the Malayali people. It is one of ...

alphabet An alphabet is a standard set of letter (alphabet), letters written to represent particular sounds in a spoken language. Specifically, letters largely correspond to phonemes as the smallest sound segments that can distinguish one word from a ...

. The scheme had been extensively used by King Marthanda Varma (1706–1758) of Travancore Kingdom and his spies both for oral and written communication of messages. It was a fixed one-time unchangeable code in as much as it did not employ any key in its implementation in contrast to modern methods of substitution ciphers involving the utilisation of a key for generating a system of codes.

The scheme

The following tables give the transposition scheme used in the ''Mulabhadra'' code.

Vowels

Consonants

Chillus

Mnemonic

The users had developed a

mnemonic A mnemonic device ( ), memory trick or memory device is any learning technique that aids information retention or retrieval in the human memory, often by associating the information with something that is easier to remember. It makes use of e ...

to learn and remember this language. The mnemonic was very similar to

Sanskrit Sanskrit (; stem form ; nominal singular , ,) is a classical language belonging to the Indo-Aryan languages, Indo-Aryan branch of the Indo-European languages. It arose in northwest South Asia after its predecessor languages had Trans-cultural ...

slokas Shloka or śloka ( , from the root , Macdonell, Arthur A., ''A Sanskrit Grammar for Students'', Appendix II, p. 232 (Oxford University Press, 3rd edition, 1927).) in a broader sense, according to Monier-Williams's dictionary, is "any verse or stan ...

. അകോഖഗോഘങശ്ചൈവ ചടോഞണതപോമനഃ യശോരഷോലസശ്ചൈവ

Examples

References

{{reflist History of cryptography Military communications Kingdom of Travancore