These pages document the use of cryptography on the Internet, in the form of links to IETF RFCs (Request For Comments) and Internet Drafts.

About the Internet Cryptography Pages

About the Internet Cryptography Web Pages

These pages provide references to the use of cryptography on the Internet, in the form of links to IETF RFCs (Request For Comments) or Internet Drafts. RFCs that define a cryptographic algorithm are highlighted in bold text. Many of the references describe the use of a cryptographic algorithm or protocol. Some references make only a passing mention of cryptography, but are included for completeness.

About IETF documents

RFCs and Internet Drafts (I-Ds) are are written and used by the Internet Engineering Task Force (IETF). I-Ds are the "working documents" of the IETF, and they are short-lived and typically dynamic. An I-D expires after six months, and can be replaced by another version of that draft; versions are indicated by the trailing digits in the name. Some I-Ds mature into RFCs, after they become stable and have been reviewed. RFCs do not expire.

Some RFCs are standards, and some are not. RFCs that describe standards are on the Standards track. The other tracks are Informational, Experimental, and Historic (see RFC 2026, The Internet Standards Process -- Revision 3). On the Internet Cryptography pages, the track of each RFC is listed along with its reference.

See below for a summary of the data notation used in IETF documents.

The IRTF Crypto Forum Research Group is the group that discusses and reviews cryptographic mechanisms for network security in general and for the IETF in particular.

Using the Internet Cryptography pages

The URLs on these pages link to the versions of RFC and Internet Drafts on the IETF Tools site. At the top of page there is a set of links to additional information, such as any intellectual property claims that have been brought to the attention of the IETF (the IPR link), other versions (the From or Versions links), and change tracking information (the Diff link).

Four types of IETF documents are listed on these pages:

  • New Internet Drafts, initial (00) versions of I-Ds,
  • Current Internet Drafts, I-Ds that have not yet expired,
  • Requests for Comments, RFCs,
  • Expired Internet Drafts, I-Ds that have expired and are no longer official IETF documents.

New drafts are listed on a separate page .


The notational conventions for IETF documents are outlined in the Data Notations section of RFC 1700 :

The convention in the documentation of Internet Protocols is to
express numbers in decimal and to picture data in "big-endian" order.
That is, fields are described left to right, with the most significant
octet on the left and the least significant octet on the right.

The order of transmission of the header and data described in this
document is resolved to the octet level.  Whenever a diagram shows a
group of octets, the order of transmission of those octets is the
normal order in which they are read in English.  For example, in the
following diagram the octets are transmitted in the order they are

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   |       1       |       2       |       3       |       4       |
   |       5       |       6       |       7       |       8       |
   |       9       |      10       |      11       |      12       |

                       Transmission Order of Bytes

Whenever an octet represents a numeric quantity the left most bit in the
diagram is the high order or most significant bit.  That is, the bit
labeled 0 is the most significant bit.  For example, the following
diagram represents the value 170 (decimal).

                          0 1 2 3 4 5 6 7
                         |1 0 1 0 1 0 1 0|

                        Significance of Bits

Similarly, whenever a multi-octet field represents a numeric quantity
the left most bit of the whole field is the most significant bit.  When
a multi-octet quantity is transmitted the most significant octet is
transmitted first.

Return to the Internet Cryptography main page.


The Internet Cryptography pages are maintained by David McGrew and are constructed by a set of text-processing scripts. They are provided in the hope that they will be useful, but without any warranty or claims of fitness for a particular purpose.

Creative Commons License
This work is licensed under a Creative Commons Attribution 3.0 Unported License.