Internet DRAFT - draft-friedl-secsh-fingerprint
INTERNET-DRAFT Markus Friedl
draft-friedl-secsh-fingerprint-00.txt The OpenBSD Project
Expires in six months March 2001
SSH Fingerprint Format
Status of this Memo
This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC2026.
Internet-Drafts are working documents of the Internet Engineering
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Distribution of this memo is unlimited.
This document formally documents the fingerprint format in use for
verifying public keys from SSH clients and servers.
The security of the SSH protocols relies on the verification of
public host keys. Since public keys tend to be very large, it is
difficult for a human to verify an entire host key. Even with a PKI
in place, it is useful to have a standard for exchanging short
fingerprints of public keys.
This document formally describes the simple key fingerprint format.
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INTERNET-DRAFT July 2000
The fingerprint of a public key consists of the output of the MD5
message-digest algorithm [RFC-1321]. The input to the algorithm is
the public key blob as described in [SSH-TRANS]. The output of the
algorithm is presented to the user as a sequence of 16 octets printed
as hexadecimal with lowercase letters and separated by colons.
For example: "4b:69:6c:72:6f:79:20:77:61:73:20:68:65:72:65:21"
[SSH-TRANS] Ylonen, T., et al: "SSH Transport Layer Protocol",
Internet Draft, draft-secsh-transport-09.txt
[RFC-1321] R. Rivest: "The MD5 Message-Digest Algorithm", April 1992.
[RFC-2026] S. Bradner: "The Internet Standards Process -- Revision
3", October 1996.
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