<!DOCTYPE html><html lang="en"><head><meta charSet="utf-8"/><meta http-equiv="X-UA-Compatible" content="IE=edge"/><title>Pulsar Overview · Apache Pulsar</title><meta name="viewport" content="width=device-width, initial-scale=1.0"/><meta name="generator" content="Docusaurus"/><meta name="description" content="Pulsar is a multi-tenant, high-performance solution for server-to-server messaging. Pulsar was originally developed by [Yahoo](http://opensource.yahoo.com/), it is under the stewardship of the [Apache Software Foundation](https://www.apache.org/)."/><meta name="docsearch:version" content="2.4.2"/><meta name="docsearch:language" content="en"/><meta property="og:title" content="Pulsar Overview · Apache Pulsar"/><meta property="og:type" content="website"/><meta property="og:url" content="https://pulsar.apache.org/"/><meta property="og:description" content="Pulsar is a multi-tenant, high-performance solution for server-to-server messaging. Pulsar was originally developed by [Yahoo](http://opensource.yahoo.com/), it is under the stewardship of the [Apache Software Foundation](https://www.apache.org/)."/><meta name="twitter:card" content="summary"/><meta name="twitter:image" content="https://pulsar.apache.org/img/pulsar.svg"/><link rel="shortcut icon" href="/img/pulsar.ico"/><link rel="stylesheet" href="//cdnjs.cloudflare.com/ajax/libs/highlight.js/9.12.0/styles/atom-one-dark.min.css"/><link rel="alternate" type="application/atom+xml" href="https://pulsar.apache.org/blog/atom.xml" title="Apache Pulsar Blog ATOM Feed"/><link rel="alternate" type="application/rss+xml" href="https://pulsar.apache.org/blog/feed.xml" title="Apache Pulsar Blog RSS Feed"/><link rel="stylesheet" href="/css/code-blocks-buttons.css"/><script type="text/javascript" src="https://buttons.github.io/buttons.js"></script><script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/clipboard.js/2.0.0/clipboard.min.js"></script><script type="text/javascript" src="/js/custom.js"></script><script src="/js/scrollSpy.js"></script><link rel="stylesheet" href="/css/main.css"/><script src="/js/codetabs.js"></script></head><body class="sideNavVisible separateOnPageNav"><div class="fixedHeaderContainer"><div class="headerWrapper wrapper"><header><a href="/en"><img class="logo" src="/img/pulsar.svg" alt="Apache Pulsar"/></a><a href="/en/versions"><h3>2.4.2</h3></a><div class="navigationWrapper navigationSlider"><nav class="slidingNav"><ul class="nav-site nav-site-internal"><li class="siteNavGroupActive"><a href="/docs/en/2.4.2/getting-started-standalone" target="_self">Docs</a></li><li class=""><a href="/en/download" target="_self">Download</a></li><li class="siteNavGroupActive"><a href="/docs/en/2.4.2/client-libraries" target="_self">Clients</a></li><li class=""><a href="#restapis" target="_self">REST APIs</a></li><li class=""><a href="#cli" target="_self">Cli</a></li><li class=""><a href="/blog/" target="_self">Blog</a></li><li class=""><a href="#community" target="_self">Community</a></li><li class=""><a href="#apache" target="_self">Apache</a></li><li class=""><a href="https://pulsar-next.staged.apache.org/" target="_self">New Website (Beta)</a></li><span><li><a id="languages-menu" href="#"><img class="languages-icon" src="/img/language.svg" alt="Languages icon"/>English</a><div id="languages-dropdown" class="hide"><ul id="languages-dropdown-items"><li><a href="/docs/ja/2.4.2/concepts-overview">日本語</a></li><li><a href="/docs/fr/2.4.2/concepts-overview">Français</a></li><li><a href="/docs/ko/2.4.2/concepts-overview">한국어</a></li><li><a href="/docs/zh-CN/2.4.2/concepts-overview">中文</a></li><li><a href="/docs/zh-TW/2.4.2/concepts-overview">繁體中文</a></li><li><a href="https://crowdin.com/project/apache-pulsar" target="_blank" rel="noreferrer noopener">Help Translate</a></li></ul></div></li><script>
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class="navListItem"><a class="navItem" href="/docs/en/2.4.2/client-libraries">Use Pulsar with client libraries</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle">Concepts and Architecture</h3><ul class=""><li class="navListItem navListItemActive"><a class="navItem" href="/docs/en/2.4.2/concepts-overview">Overview</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/concepts-messaging">Messaging</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/concepts-architecture-overview">Architecture</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/concepts-clients">Clients</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/concepts-replication">Geo Replication</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/concepts-multi-tenancy">Multi Tenancy</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/concepts-authentication">Authentication and Authorization</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/concepts-topic-compaction">Topic Compaction</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/concepts-tiered-storage">Tiered Storage</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/concepts-schema-registry">Schema Registry</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle">Pulsar Schema</h3><ul class=""><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/schema-get-started">Get started</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/schema-understand">Understand schema</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/schema-evolution-compatibility">Schema evolution and compatibility</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/schema-manage">Manage schema</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle">Pulsar Functions</h3><ul class=""><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/functions-overview">Overview</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/functions-worker">Setup: Pulsar Functions Worker</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/functions-runtime">Setup: Configure Functions runtime</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/functions-develop">How-to: Develop</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/functions-debug">How-to: Debug</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/functions-deploy">How-to: Deploy</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/functions-cli">Reference: CLI</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/window-functions-context">Window Functions: Context</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle">Pulsar IO</h3><ul class=""><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/io-overview">Overview</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/io-quickstart">Get started</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/io-use">Use</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/io-managing">Managing Connectors</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/io-debug">Debug</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/io-connectors">Builtin Connectors</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/io-develop">Developing Connectors</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/io-cdc">CDC Connector</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle">Pulsar SQL</h3><ul class=""><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/sql-overview">Overview</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/sql-getting-started">Get Started</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/sql-deployment-configurations">Deployment and Configuration</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle">Deployment</h3><ul class=""><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/deploy-aws">Amazon Web Services</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/deploy-kubernetes">Kubernetes</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/deploy-bare-metal">Bare metal</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/deploy-bare-metal-multi-cluster">Bare metal multi-cluster</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/deploy-monitoring">Monitoring</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle">Administration</h3><ul class=""><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/administration-zk-bk">ZooKeeper and BookKeeper</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/administration-geo">Geo-replication</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/administration-dashboard">Dashboard</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/administration-stats">Pulsar statistics</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/administration-load-balance">Load balance</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/administration-proxy">Pulsar proxy</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/administration-upgrade">Upgrade</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle">Security</h3><ul class=""><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/security-overview">Overview</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/security-tls-transport">Transport Encryption using TLS</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/security-tls-authentication">Authentication using TLS</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/security-token-client">Client Authentication using tokens</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/security-token-admin">Token authentication admin</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/security-athenz">Authentication using Athenz</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/security-kerberos">Authentication using Kerberos</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/security-jwt">Authentication using JWT</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/security-authorization">Authorization and ACLs</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/security-encryption">End-to-End Encryption</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/security-extending">Extending</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle">Client Libraries</h3><ul class=""><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/client-libraries-java">Java</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/client-libraries-go">Go</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/client-libraries-python">Python</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/client-libraries-cpp">C++</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/client-libraries-websocket">WebSocket</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle">Admin API</h3><ul class=""><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/admin-api-overview">Overview</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/admin-api-clusters">Clusters</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/admin-api-tenants">Tenants</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/admin-api-brokers">Brokers</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/admin-api-namespaces">Namespaces</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/admin-api-permissions">Permissions</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/admin-api-persistent-topics">Persistent topics</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/admin-api-non-persistent-topics">Non-Persistent topics</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/admin-api-partitioned-topics">Partitioned topics</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/admin-api-schemas">Schemas</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/admin-api-functions">Functions</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle">Adaptors</h3><ul class=""><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/adaptors-kafka">Kafka client wrapper</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/adaptors-spark">Apache Spark</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/adaptors-storm">Apache Storm</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle">Cookbooks</h3><ul class=""><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/cookbooks-tiered-storage">Tiered Storage</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/cookbooks-compaction">Topic compaction</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/cookbooks-deduplication">Message deduplication</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/cookbooks-non-persistent">Non-persistent messaging</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/cookbooks-partitioned">Partitioned Topics</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/cookbooks-retention-expiry">Message retention and expiry</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/cookbooks-encryption">Encryption</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/cookbooks-message-queue">Message queue</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/cookbooks-bookkeepermetadata">BookKeeper Ledger Metadata</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle">Development</h3><ul class=""><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/develop-tools">Simulation tools</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/developing-binary-protocol">Binary protocol</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/develop-schema">Custom schema storage</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/develop-load-manager">Modular load manager</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/develop-cpp">Building Pulsar C++ client</a></li></ul></div><div class="navGroup"><h3 class="navGroupCategoryTitle">Reference</h3><ul class=""><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/reference-terminology">Terminology</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/reference-cli-tools">Pulsar CLI tools</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/reference-connector-admin">Connector Admin CLI</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/reference-configuration">Pulsar configuration</a></li><li class="navListItem"><a class="navItem" href="/docs/en/2.4.2/reference-metrics">Pulsar Metrics</a></li></ul></div></div></section></div><script>
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<p>Key features of Pulsar are listed below:</p>
<ul>
<li>Native support for multiple clusters in a Pulsar instance, with seamless <a href="/docs/en/2.4.2/administration-geo">geo-replication</a> of messages across clusters.</li>
<li>Very low publish and end-to-end latency.</li>
<li>Seamless scalability to over a million topics.</li>
<li>A simple <a href="/docs/en/2.4.2/concepts-clients">client API</a> with bindings for <a href="/docs/en/2.4.2/client-libraries-java">Java</a>, <a href="/docs/en/2.4.2/client-libraries-go">Go</a>, <a href="/docs/en/2.4.2/client-libraries-python">Python</a> and <a href="/docs/en/2.4.2/client-libraries-cpp">C++</a>.</li>
<li>Multiple <a href="/docs/en/2.4.2/concepts-messaging#subscription-types">subscription types</a> (<a href="/docs/en/2.4.2/concepts-messaging#exclusive">exclusive</a>, <a href="/docs/en/2.4.2/concepts-messaging#shared">shared</a>, and <a href="/docs/en/2.4.2/concepts-messaging#failover">failover</a>) for topics.</li>
<li>Guaranteed message delivery with <a href="/docs/en/2.4.2/concepts-architecture-overview#persistent-storage">persistent message storage</a> provided by <a href="http://bookkeeper.apache.org/">Apache BookKeeper</a>.</li>
<li>A serverless light-weight computing framework <a href="/docs/en/2.4.2/functions-overview">Pulsar Functions</a> offers the capability for stream-native data processing.</li>
<li>A serverless connector framework <a href="/docs/en/2.4.2/io-overview">Pulsar IO</a>, which is built on Pulsar Functions, makes it easier to move data in and out Apache Pulsar.</li>
<li><a href="/docs/en/2.4.2/concepts-tiered-storage">Tiered Storage</a> offloads data from hot/warm storage to cold/longterm storage (such as S3 and GCS) when the data is aging out.</li>
</ul>
<h2><a class="anchor" aria-hidden="true" id="contents"></a><a href="#contents" aria-hidden="true" class="hash-link"><svg class="hash-link-icon" aria-hidden="true" height="16" version="1.1" viewBox="0 0 16 16" width="16"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Contents</h2>
<ul>
<li><a href="/docs/en/2.4.2/concepts-messaging">Messaging Concepts</a></li>
<li><a href="/docs/en/2.4.2/concepts-architecture-overview">Architecture Overview</a></li>
<li><a href="/docs/en/2.4.2/concepts-clients">Pulsar Clients</a></li>
<li><a href="/docs/en/2.4.2/concepts-replication">Geo Replication</a></li>
<li><a href="/docs/en/2.4.2/concepts-multi-tenancy">Multi Tenancy</a></li>
<li><a href="/docs/en/2.4.2/concepts-authentication">Authentication and Authorization</a></li>
<li><a href="/docs/en/2.4.2/concepts-topic-compaction">Topic Compaction</a></li>
<li><a href="/docs/en/2.4.2/concepts-tiered-storage">Tiered Storage</a></li>
<li><a href="/docs/en/2.4.2/concepts-schema-registry">Schema Registry</a></li>
</ul>
</span></div></article></div><div class="docs-prevnext"><a class="docs-prev button" href="/docs/en/2.4.2/client-libraries"><span class="arrow-prev">← </span><span>Overview</span></a><a class="docs-next button" href="/docs/en/2.4.2/concepts-messaging"><span>Messaging</span><span class="arrow-next"> →</span></a></div></div></div><nav class="onPageNav"><ul class="toc-headings"><li><a href="#contents">Contents</a></li></ul></nav></div><footer class="nav-footer" id="footer"><section class="copyright">Copyright © 2022 The Apache Software Foundation. All Rights Reserved. Apache, Apache Pulsar and the Apache feather logo are trademarks of The Apache Software Foundation.</section><span><script>
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