<titledata-rh="true">Glossary | Waku Documentation</title><metadata-rh="true"name="viewport"content="width=device-width,initial-scale=1"><metadata-rh="true"name="twitter:card"content="summary_large_image"><metadata-rh="true"property="og:url"content="https://docs.waku.org/learn/glossary"><metadata-rh="true"property="og:locale"content="en_GB"><metadata-rh="true"name="docusaurus_locale"content="en-GB"><metadata-rh="true"name="docsearch:language"content="en-GB"><metadata-rh="true"name="keywords"content="waku, web3"><metadata-rh="true"name="image"content="https://docs.waku.org/_og/42f419aeef2eb912fac6f2a139bfae726493eff7.png"><metadata-rh="true"name="docusaurus_version"content="current"><metadata-rh="true"name="docusaurus_tag"content="docs-default-current"><metadata-rh="true"name="docsearch:version"content="current"><metadata-rh="true"name="docsearch:docusaurus_tag"content="docs-default-current"><metadata-rh="true"property="og:title"content="Glossary | Waku Documentation"><metadata-rh="true"name="description"content="Definitions and usage of the terminology used in the Waku ecosystem."><metadata-rh="true"property="og:description"content="Definitions and usage of the terminology used in the Waku ecosystem."><linkdata-rh="true"rel="icon"href="/theme/image/favicon.ico"><linkdata-rh="true"rel="canonical"href="https://docs.waku.org/learn/glossary"><linkdata-rh="true"rel="alternate"href="https://docs.waku.org/learn/glossary"hreflang="en-GB"><linkdata-rh="true"rel="alternate"href="https://docs.waku.org/learn/glossary"hreflang="x-default"><linkrel="alternate icon"type="image/png"href="/theme/image/favicon.png">
<p>Definitions and usage of the terminology used in the Waku ecosystem.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="bootstrapping">Bootstrapping<ahref="#bootstrapping"class="hash-link"aria-label="Direct link to Bootstrapping"title="Direct link to Bootstrapping"></a></h3>
<p>Bootstrapping is the initial entry point of a <ahref="#node">node</a> to the <ahref="#waku-network">Waku Network</a>. Once connected, other <ahref="#peer-discovery">peer discovery</a> methods can be employed to locate other <ahref="#peer">peers</a> in the network.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="content-topic"><ahref="/learn/concepts/content-topics">Content topic</a><ahref="#content-topic"class="hash-link"aria-label="Direct link to content-topic"title="Direct link to content-topic"></a></h3>
<p>A content topic is a string attached to <ahref="#waku-message">messages</a> to enable <ahref="#protocol">protocol-level</a> features like selective message processing and retrieval based on specific criteria.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="dappnode"><ahref="https://dappnode.com/"target="_blank"rel="noopener noreferrer">Dappnode</a><ahref="#dappnode"class="hash-link"aria-label="Direct link to dappnode"title="Direct link to dappnode"></a></h3>
<p>Dappnode is an open-source platform that simplifies the hosting and management of decentralised applications and blockchain nodes, including <ahref="#waku">Waku</a>.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="discv5"><ahref="/learn/concepts/discv5">Discv5</a><ahref="#discv5"class="hash-link"aria-label="Direct link to discv5"title="Direct link to discv5"></a></h3>
<p>Discv5 is a <ahref="#peer-discovery">peer discovery</a> mechanism using a Distributed Hash Table (DHT) to store <ahref="#enr">ENR</a> records, providing censorship resistance, load distribution, and enhanced network resilience.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="dns-discovery"><ahref="/learn/concepts/dns-discovery">DNS discovery</a><ahref="#dns-discovery"class="hash-link"aria-label="Direct link to dns-discovery"title="Direct link to dns-discovery"></a></h3>
<p>DNS discovery is a <ahref="#peer-discovery">peer discovery</a> mechanism that allows the retrieval of an <ahref="#enr">ENR</a> tree from the TXT field of a domain name, enabling the storage of <ahref="#node">node</a> connection details and promoting decentralisation.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="enr"><ahref="https://eips.ethereum.org/EIPS/eip-778"target="_blank"rel="noopener noreferrer">ENR</a><ahref="#enr"class="hash-link"aria-label="Direct link to enr"title="Direct link to enr"></a></h3>
<p>Ethereum Node Record (ENR) is a specification used to represent and identify <ahref="#node">nodes</a>, facilitating <ahref="#peer-discovery">discovery</a> and communication within the network. Besides connection details, <code>ENR</code> also includes node configuration information like enabled protocol and shards.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="filter"><ahref="/learn/concepts/protocols#filter">Filter</a><ahref="#filter"class="hash-link"aria-label="Direct link to filter"title="Direct link to filter"></a></h3>
<p>Filter is a <ahref="#protocol">protocol</a> that enables <ahref="#light-node">light nodes</a> to selectively subscribe to specific <ahref="#waku-message">messages</a> transmitted by <ahref="#peer">peers</a> using <ahref="#content-topic">content topics</a>. It is designed to be a lightweight alternative for accessing the <ahref="#relay">Relay</a> network.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="gossipsub"><ahref="/learn/concepts/network-domains#gossip-domain">GossipSub</a><ahref="#gossipsub"class="hash-link"aria-label="Direct link to gossipsub"title="Direct link to gossipsub"></a></h3>
<p>GossipSub is a <ahref="#protocol">protocol</a> for efficient and scalable information dissemination in decentralised networks commonly used in blockchain systems.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="libp2p"><ahref="https://libp2p.io/"target="_blank"rel="noopener noreferrer">Libp2p</a><ahref="#libp2p"class="hash-link"aria-label="Direct link to libp2p"title="Direct link to libp2p"></a></h3>
<p>Libp2p is a modular network stack and protocol suite that allows developers to build decentralised, peer-to-peer applications across various network protocols.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="light-node">Light node<ahref="#light-node"class="hash-link"aria-label="Direct link to Light node"title="Direct link to Light node"></a></h3>
<p>A light node is a <ahref="#resource-limited">resource-limited</a> device or client that leverages service nodes to access the <ahref="#relay">Relay</a> network.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="light-push"><ahref="/learn/concepts/protocols#light-push">Light push</a><ahref="#light-push"class="hash-link"aria-label="Direct link to light-push"title="Direct link to light-push"></a></h3>
<p>Light push is a protocol enabling <ahref="#light-node">light nodes</a> to send <ahref="#waku-message">messages</a> to the <ahref="#relay">Relay</a> network and receive acknowledgements confirming that a <ahref="#peer">peer</a> has received them.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="mostly-offline">Mostly offline<ahref="#mostly-offline"class="hash-link"aria-label="Direct link to Mostly offline"title="Direct link to Mostly offline"></a></h3>
<p>Mostly offline devices are clients who spend most of their time offline or disconnected from the internet and only occasionally to the internet and <ahref="#waku-network">Waku Network</a>. Examples include browsers and mobile phones.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="node">Node<ahref="#node"class="hash-link"aria-label="Direct link to Node"title="Direct link to Node"></a></h3>
<p>A node is a device or client that implements Waku <ahref="#protocol">protocols</a> and leverages the <ahref="#waku-network">Waku Network</a> to enable secure and private peer-to-peer web3 communication.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="node-key">Node key<ahref="#node-key"class="hash-link"aria-label="Direct link to Node key"title="Direct link to Node key"></a></h3>
<p>A node key is a <ahref="https://en.bitcoin.it/wiki/Secp256k1"target="_blank"rel="noopener noreferrer">Secp256k1</a> (64-char hex string) private key for generating the <ahref="#peer-id">PeerID</a>, <ahref="#transport">listening</a> addresses, and <ahref="#peer-discovery">discovery</a> addresses of a Waku node.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="out-of-band">Out-of-band<ahref="#out-of-band"class="hash-link"aria-label="Direct link to Out-of-band"title="Direct link to Out-of-band"></a></h3>
<p>Out-of-band refers to exchanging information through a separate, secure channel distinct from the main communication method to enhance security.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="payload">Payload<ahref="#payload"class="hash-link"aria-label="Direct link to Payload"title="Direct link to Payload"></a></h3>
<p>The payload field in a <ahref="#waku-message">Waku Message</a> contains the application data, serving as the business logic message transmitted between clients over Waku. Applications can encrypt the payload or employ encryption methods specified in <ahref="#waku-message-payload-encryption">Waku Message Payload Encryption</a>.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="peer">Peer<ahref="#peer"class="hash-link"aria-label="Direct link to Peer"title="Direct link to Peer"></a></h3>
<p>A peer refers to other <ahref="#node">nodes</a> and participants of the <ahref="#waku-network">Waku Network</a> with whom communication and interaction are possible.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="peer-discovery"><ahref="/learn/concepts/peer-discovery">Peer discovery</a><ahref="#peer-discovery"class="hash-link"aria-label="Direct link to peer-discovery"title="Direct link to peer-discovery"></a></h3>
<p>Peer discovery is when a <ahref="#node">node</a> locates and gets information about other <ahref="#peer">peers</a> in the <ahref="#waku-network">Waku Network</a>.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="peer-exchange"><ahref="/learn/concepts/peer-exchange">Peer exchange</a><ahref="#peer-exchange"class="hash-link"aria-label="Direct link to peer-exchange"title="Direct link to peer-exchange"></a></h3>
<p>Peer exchange is a <ahref="#peer-discovery">peer discovery</a> mechanism that enables <ahref="#light-node">light nodes</a> to request and receive peers from other nodes in the network, allowing them to bootstrap and expand their connections without depending on <ahref="#discv5">Discv5</a>.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="peer-id">Peer ID<ahref="#peer-id"class="hash-link"aria-label="Direct link to Peer ID"title="Direct link to Peer ID"></a></h3>
<p><code>PeerID</code> is the unique identifier of a <ahref="#node">node</a> in the <ahref="#waku-network">Waku Network</a> generated from the cryptographic hash of the node's public key.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="protocol"><ahref="/learn/concepts/protocols">Protocol</a><ahref="#protocol"class="hash-link"aria-label="Direct link to protocol"title="Direct link to protocol"></a></h3>
<p>A protocol is a set of rules that enables <ahref="#node">nodes</a> within the <ahref="#waku-network">Waku Network</a> to perform various functionalities such as message sending, relaying, filtering, storing, retrieving, and more.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="pubsub">Pub/Sub<ahref="#pubsub"class="hash-link"aria-label="Direct link to Pub/Sub"title="Direct link to Pub/Sub"></a></h3>
<p>Publish/Subscribe (Pub/Sub) is an asynchronous messaging pattern where publishers send messages to topics, and subscribers receive messages from topics of interest, allowing efficient one-to-many communication.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="pubsub-topic">Pub/Sub topic<ahref="#pubsub-topic"class="hash-link"aria-label="Direct link to Pub/Sub topic"title="Direct link to Pub/Sub topic"></a></h3>
<p>A Pub/Sub topic is a string that serves as an identifier for the topic of interest among <ahref="#gossipsub">GossipSub</a> peers. Peers interested in the same topic are likely to maintain a connection and forward messages received on that topic.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="rate-limit-nullifiers"><ahref="https://rate-limiting-nullifier.github.io/rln-docs/"target="_blank"rel="noopener noreferrer">Rate limit nullifiers</a><ahref="#rate-limit-nullifiers"class="hash-link"aria-label="Direct link to rate-limit-nullifiers"title="Direct link to rate-limit-nullifiers"></a></h3>
<p>Rate Limit Nullifiers (RLN) are a construct based on zero-knowledge proofs that enables rate limiting functionality while preserving the users's anonymity.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="relay"><ahref="/learn/concepts/protocols#relay">Relay</a><ahref="#relay"class="hash-link"aria-label="Direct link to relay"title="Direct link to relay"></a></h3>
<p>Relay is a <ahref="#protocol">protocol</a> that extends the <ahref="#gossipsub">GossipSub protocol</a> to enable secure and censorship resistant <ahref="#waku-message">message</a> sending and receiving among <ahref="#peer">peers</a> while preserving privacy. It also scales the <ahref="#waku-network">Waku Network</a> to accommodate many nodes efficiently.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="resource-limited">Resource-limited<ahref="#resource-limited"class="hash-link"aria-label="Direct link to Resource-limited"title="Direct link to Resource-limited"></a></h3>
<p>Resource-limited refers to environments or devices restricting available resources, including bandwidth, CPU, memory, disk, and battery power.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="rln-relay"><ahref="/learn/concepts/protocols#rln-relay">RLN relay</a><ahref="#rln-relay"class="hash-link"aria-label="Direct link to rln-relay"title="Direct link to rln-relay"></a></h3>
<p>RLN Relay is an extension of the <ahref="#relay">Relay protocol</a> that uses <ahref="#rate-limit-nullifiers">Rate Limit Nullifiers (RLN)</a> to prevent spam economically by enforcing a rate limit on messages over time, imposing penalties, and facilitating network removal for spammers.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="sdk"><ahref="/">SDK</a><ahref="#sdk"class="hash-link"aria-label="Direct link to sdk"title="Direct link to sdk"></a></h3>
<p>SDKs are tools, libraries, and resources to integrate Waku's private, secure, and censorship-free communication features into various applications.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="store"><ahref="/learn/concepts/protocols#store">Store</a><ahref="#store"class="hash-link"aria-label="Direct link to store"title="Direct link to store"></a></h3>
<p>Store is a <ahref="#protocol">protocol</a> that enables the storage of relayed <ahref="#waku-message">messages</a> in the network, allowing offline peers to retrieve missed messages upon reconnecting to the network.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="transport"><ahref="/learn/concepts/transports">Transport</a><ahref="#transport"class="hash-link"aria-label="Direct link to transport"title="Direct link to transport"></a></h3>
<p>A transport is a network mechanism that establishes connections between <ahref="#peer">peers</a> and enables efficient transmission, routing, and delivery of data packets.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="waku">Waku<ahref="#waku"class="hash-link"aria-label="Direct link to Waku"title="Direct link to Waku"></a></h3>
<p>Waku is a family of private, secure, decentralised, and peer-to-peer web3 communication <ahref="#protocol">protocols</a> designed to operate in <ahref="#resource-limited">resource-limited</a> environments and suitable for <ahref="#node">node</a> or desktop application use. Additionally, these protocols collectively form the <ahref="#waku-network">Waku Network</a>.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="waku-message"><ahref="/learn/concepts/protocols#waku-message">Waku message</a><ahref="#waku-message"class="hash-link"aria-label="Direct link to waku-message"title="Direct link to waku-message"></a></h3>
<p>Waku Message defines the structure of messages in the <ahref="#waku-network">Waku Network</a>, including the <ahref="#content-topic">content topic</a>, <ahref="#payload">payload</a>, and metadata for application-specific processing.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="waku-message-payload-encryption"><ahref="https://rfc.vac.dev/waku/standards/application/26/payload"target="_blank"rel="noopener noreferrer">Waku message payload encryption</a><ahref="#waku-message-payload-encryption"class="hash-link"aria-label="Direct link to waku-message-payload-encryption"title="Direct link to waku-message-payload-encryption"></a></h3>
<p>Waku Message Payload Encryption provides guidelines for implementing secure and private communication in the <ahref="#waku-network">Waku Network</a>. It covers encryption, decryption, and signing methods for message <ahref="#payload">payloads</a>, focusing on confidentiality, authenticity, integrity, and unlinkability.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="waku-network"><ahref="/learn/">Waku network</a><ahref="#waku-network"class="hash-link"aria-label="Direct link to waku-network"title="Direct link to waku-network"></a></h3>
<p>The Waku Network is an open-access, scalable peer-to-peer messaging network emphasizing privacy protection and accessibility to <ahref="#resource-limited">resource limited</a> devices.</p>
<h3class="anchor anchorWithHideOnScrollNavbar_WYt5"id="waku-noise">Waku noise<ahref="#waku-noise"class="hash-link"aria-label="Direct link to Waku noise"title="Direct link to Waku noise"></a></h3>
