> For the complete documentation index, see [llms.txt](https://docs.editran.onesait.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.editran.onesait.com/documentacion-editran/connect-v3.1-en/firma.md). # Signature The *digital signature* is a mechanism that irrevocably associates certain content with one or more identities. The content is the file being signed and each identity is represented by a digital certificate. This association is carried out using mathematical encryption operations that use the private (for signing) and public (for verification) keys associated with the digital certificates used. From the moment a digital signature is produced for a document, the following are guaranteed: * The **document integrity**: any modification made to the file after signing would be detected during signature verification. * The **authorship** of the signature: each digital certificate used is uniquely associated with the natural or legal person it represents. * **Origin non-repudiation**: the private key used to encrypt is only accessible to the natural or legal person it represents, and only that person knows the mechanism used to keep it protected (PIN, password, etc.), so once it has been used, the author cannot repudiate it. Connect includes all operations that require signing and verification of file signatures before and after being exchanged between two endpoints. For this functionality, available under a specific license, the following elements are essential: * ***Channel***** of Connect with the signing feature** in the corresponding direction of transmission: * In sending, when it is a *channel* through which files (signed or not) will be sent that have previously undergone signing processing in the local installation. * In receiving, when the *channel* will receive and verify signatures performed (with Connect or not) at other endpoints. * Roles and users: * **User with signer role**: this is the one who accesses Connect to sign the files. Their configuration profile contains the public key digital certificates that represent them. To perform the signatures, the signer must have the **private key certificates** corresponding to the public key ones mentioned in their configuration. * **Remote signer**: associated with a *contact* in Connect, this is the author of signatures generated at another endpoint that are subsequently received and verified here. Their configuration profile contains the public key digital certificates that represent them. * ***File group***: is the set of parameters that define a signing rule. In a *file group* it specifies **which** files must be signed (location, banking format/standard), **how** (PKCS#7 or XAdES signing mode) and **who** and **how many** must do so. Signing rules can be established based exclusively on the signers' criteria (signatories, their groupings, and required signatures) or also taking into account certain data provided in the files being signed (tax ID, account, largest transaction amount, total file amount, etc.). They can have two purposes: signing files or verifying signatures. Below, the administration tasks for the module are detailed, as well as the use of the product once configured, both for signing files and for verifying signatures. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://docs.editran.onesait.com/documentacion-editran/connect-v3.1-en/firma.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.