This NSS documentation was just imported from our legacy MDN repository. It currently is very deprecated and likely incorrect or broken in many places.

More Documentation

Network Security Services (NSS) is a set of libraries designed to support cross-platform development of security-enabled client and server applications. Applications built with NSS can support SSL v3, TLS, PKCS #5, PKCS #7, PKCS #11, PKCS #12, S/MIME, X.509 v3 certificates, and other security standards.

For detailed information on standards supported, see mozilla_projects_nss_overview. For a list of frequently asked questions, see the mozilla_projects_nss_faq.

NSS is available under the Mozilla Public License. For information on downloading NSS releases as tar files, see mozilla_projects_nss_nss_sources_building_testing.

If you’re a developer and would like to contribute to NSS, you might want to read the documents mozilla_projects_nss_an_overview_of_nss_internals and Getting Started With NSS.

Background Information


Provides a brief summary of NSS and its capabilities.


Answers basic questions about NSS.

Introduction to Public-Key Cryptography

Explains the basic concepts of public-key cryptography that underlie NSS.

Introduction to SSL

Introduces the SSL protocol, including information about cryptographic ciphers supported by SSL and the steps involved in the SSL handshake.

Getting Started


This page contains information about the current and past releases of NSS.


Instructions on how to build NSS on the different supported platforms.

Get Mozilla Source Code Using Mercurial

Information about with working with Mercurial.

Get Mozilla Source Code Using CVS (deprecated)

Old deprecated CVS documentation.


Introduction to Network Security Services

Provides an overview of the NSS libraries and what you need to know to use them.


Summarizes the SSL APIs exported by the NSS shared libraries.


API used to invoke SSL operations.


Explains how the libraries and code are organized, and guidelines for developing code (naming conventions, error handling, thread safety, etc.)


Links to NSS technical notes, which provide latest information about new NSS features and supplementary documentation for advanced topics in programming with NSS.

Tools, testing, and other technical details


Describe how to check out and build NSS releases.


How to make changes in NSS. Coding style, maintaining ABI compatibility.


Tools for developing, debugging, and managing applications that use NSS.


Demonstrates how NSS can be used for cryptographic operations, certificate handling, SSL, etc.


A list of third-party code included in the NSS library.

NSS 3.2 Test Suite

Archived version. Describes how to run the standard NSS tests.

NSS Performance Reports

Archived version. Links to performance reports for NSS 3.2 and later releases.

Encryption Technologies Available in NSS 3.11

Archived version. Lists the cryptographic algorithms used by NSS 3.11.

NSS 3.1 Loadable Root Certificates

Archived version. Describes the scheme for loading root CA certificates.


Archived version. General format of the cert7.db database.

PKCS #11 information

CA certificates pre-loaded into NSS

NSS is built on top of Netscape Portable Runtime (NSPR)

Netscape Portable Runtime

NSPR project page.

NSPR Reference

NSPR API documentation.

Additional Information

  • Using the window.crypto object from JavaScript

  • mozilla_projects_nss_http_delegation

  • mozilla_projects_nss_tls_cipher_suite_discovery

  • mozilla_projects_nss_certificate_download_specification

  • mozilla_projects_nss_fips_mode_-_an_explanation

  • mozilla_projects_nss_key_log_format


Information on NSS planning can be found at wiki.mozilla.org, including: