RFC 3126 Electronic Signature Formats September 2001 Table of Contents 1. Introduction 4 2 Overview 5 2.1 Aim 5 2.2 Basis of Present Document 5 2.3 Major Parties 6 2.4 Electronic Signatures and Validation Data 7 2.5 Forms of Validation Data 8 2.6 Extended Forms of Validation Data 11 2.7 Archive Validation Data 13 2.8 Arbitration 15 2.9 Validation Process 15 2.10 Example Validation Sequence 16 2.11 Additional optional features 21 3. Data structure of an Electronic Signature 22 3.1 General Syntax 22 3.2 Data Content Type 22 3.3 Signed-data Content Type 22 3.4 SignedData Type 22 3.5 EncapsulatedContentInfo Type 23 3.6 SignerInfo Type 23 3.6.1 Message Digest Calculation Process 23 3.6.2 Message Signature Generation Process 24 3.6.3 Message Signature Verification Process 24 3.7 CMS Imported Mandatory Present Attributes 24 3.7.1 Content Type 24 3.7.2 Message Digest 24 3.7.3 Signing Time 24 3.8 Alternative Signing Certificate Attributes 24 3.8.1 ESS Signing Certificate Attribute Definition 25 3.8.2 Other Signing Certificate Attribute Definition 25 3.9 Additional Mandatory Attributes 26 3.9.1 Signature policy Identifier 26 3.10 CMS Imported Optional Attributes 28 3.10.1 Countersignature 29 3.11 ESS Imported Optional Attributes 29 3.11.1 Content Reference Attribute 29 3.11.2 Content Identifier Attribute 29 3.11.3 Content Hints Attribute 29 3.12 Additional Optional Attributes 30 3.12.1 Commitment Type Indication Attribute 30 3.12.2 Signer Location attribute 32 3.12.3 Signer Attributes attribute 33 3.12.4 Content Time-Stamp attribute 34 3.13 Support for Multiple Signatures 34 3.13.1 Independent Signatures 34 3.13.2 Embedded Signatures 34 Pinkas, et al. Informational