Glossary
This page defines DoubleZero-specific terminology used throughout the documentation.
Network Infrastructure
DZD (DoubleZero Device)
The physical network switching hardware that terminates DoubleZero links and runs the DoubleZero Agent software. DZDs are deployed at data centers and provide routing, packet processing, and user connectivity services. Each DZD requires specific hardware specifications and runs both the Config Agent and Telemetry Agent.
DZX (DoubleZero Exchange)
Interconnect points in the mesh network where different contributor links are bridged together. DZXs are located in major metropolitan areas (e.g., NYC, LON, TYO) where network intersections occur. Network contributors must cross-connect their links into the broader DoubleZero mesh at the nearest DZX. Similar in concept to an Internet Exchange (IX).
WAN Link
A Wide Area Network link between two DZDs operated by the same contributor. WAN links provide backbone connectivity within a single contributor's infrastructure.
DZX Link
A link between DZDs operated by different contributors, established at a DZX. DZX links require explicit acceptance by both parties.
DZ Prefix
IP address allocations in CIDR format assigned to a DZD for overlay network addressing. Specified during device creation using the --dz-prefixes parameter.
Device Types
Edge Device
A DZD that provides user connectivity to the DoubleZero network. Edge devices leverage CYOA interfaces to terminate users (validators, RPC operators) and connect them to the network.
Transit Device
A DZD that provides backbone connectivity within the DoubleZero network. Transit devices move traffic between DZDs but do not terminate user connections directly.
Hybrid Device
A DZD that combines both edge and transit functionality, providing both user connectivity and backbone routing.
Connectivity
CYOA (Choose Your Own Adventure)
Interface types that allow contributors to register connectivity options for users to connect to the DoubleZero network. CYOA interfaces include various methods like DIA, GRE tunnels, and private peering. See Creating CYOA Interfaces for configuration details.
DIA (Direct Internet Access)
A standard networking term for connectivity provided over the public internet. In DoubleZero, DIA is a CYOA interface type where users (validators, RPC operators) connect to a DZD over their existing internet connection.
IBRL (Increase Bandwidth Reduce Latency)
A connection mode that allows validators and RPC nodes to connect to DoubleZero without restarting their blockchain clients. IBRL uses the existing public IP address and establishes an overlay tunnel to the nearest DZD. See Mainnet-Beta Connection for setup instructions.
Multicast
A one-to-many packet delivery method supported by DoubleZero. Multicast mode has two roles: publisher (sends packets across the network) and subscriber (receives packets from the publisher). Used by development teams for efficient data distribution. See Multicast Connection for connection details.
Software Components
doublezerod
The DoubleZero daemon service that runs on user servers (validators, RPC nodes). It manages the connection to the DoubleZero network, handles tunnel establishment, and maintains connectivity to DZDs. Configured via systemd and controlled through the doublezero CLI.
doublezero (CLI)
The command-line interface for interacting with the DoubleZero network. Used for connecting, managing identities, checking status, and administrative operations. Communicates with the doublezerod daemon.
Config Agent
Software agent running on DZDs that manages device configuration. Reads configuration from the Controller service and applies changes to the device. See Config Agent Installation for setup.
Telemetry Agent
Software agent running on DZDs that collects performance metrics (latency, jitter, packet loss) and submits them to the DoubleZero ledger. See Telemetry Agent Installation for setup.
Controller
A service that provides configuration to DZD agents. The Controller derives device configurations from onchain state on the DoubleZero ledger.
Link States
Activated
The normal operational state for a link. Traffic flows through the link and it participates in routing decisions.
Soft-Drained
A maintenance state where traffic will be discouraged on a specific link. Used for graceful maintenance windows. Can transition to activated or hard-drained.
Hard-Drained
A maintenance state where the link is completely removed from service. No traffic flows through the link. Must transition to soft-drained before returning to activated.
Organizations & Tokens
DZF (DoubleZero Foundation)
The DoubleZero Foundation, the organization overseeing the development and governance of the DoubleZero protocol.
2Z Token
The native token of the DoubleZero network. Used for paying validator fees and distributed as rewards to contributors. Validators can pay fees in 2Z via an onchain swap program. See Paying Fees with 2Z and Swapping SOL to 2Z.
Contributor
A network infrastructure provider who contributes bandwidth and hardware to the DoubleZero network. Contributors operate DZDs, provide WAN and DZX links, and receive 2Z token incentives for their contribution. See Contributor Documentation to get started.
Networking Concepts
MTU (Maximum Transmission Unit)
The largest packet size (in bytes) that can be transmitted over a network link. DoubleZero WAN links typically use MTU 9000 (jumbo frames) for efficiency.
VRF (Virtual Routing and Forwarding)
A technology that allows multiple isolated routing tables to exist on the same physical router. Contributors often use a separate management VRF to isolate switch management traffic from production traffic.
GRE (Generic Routing Encapsulation)
A tunneling protocol that encapsulates network packets inside IP packets. Used by IBRL and CYOA connections to create overlay tunnels between users and DZDs.
BGP (Border Gateway Protocol)
The routing protocol used for exchanging routing information between networks on the internet. DoubleZero uses BGP internally with ASN 65342.
ASN (Autonomous System Number)
A unique identifier assigned to a network for BGP routing. All DoubleZero devices use ASN 65342 for the internal BGP process.
Loopback Interface
A virtual network interface on a router/switch used for management and routing purposes. DZDs use Loopback255 (VPNv4) and Loopback256 (IPv4) for internal routing.
CIDR (Classless Inter-Domain Routing)
A notation for specifying IP address ranges. The format is IP/prefix-length where the prefix length indicates network size (e.g., /29 = 8 addresses, /24 = 256 addresses).
Jitter
Variation in packet latency over time. Low jitter is critical for real-time applications.
RTT (Round-Trip Time)
The time for a packet to travel from source to destination and back. Used to measure network latency between devices.
TWAMP (Two-Way Active Measurement Protocol)
A protocol for measuring network performance metrics like latency and packet loss. The Telemetry Agent uses TWAMP to collect metrics between DZDs.
IS-IS (Intermediate System to Intermediate System)
A link-state routing protocol used internally by the DoubleZero network. IS-IS metrics are adjusted during link draining operations.
Blockchain & Keys
Onchain
In the DoubleZero context, onchain refers to data and operations recorded on the DoubleZero ledger. Unlike traditional networks where device and link configurations live in centralized management systems, DoubleZero records device registrations, link configurations, and telemetry submissions onchain — making the network state transparent and verifiable by all participants.
Service Key
A cryptographic keypair used to authenticate CLI operations. This is your contributor identity for interacting with the DoubleZero smart contract. Stored at ~/.config/solana/id.json.
Metrics Publisher Key
A cryptographic keypair used by the Telemetry Agent to sign metric submissions to the blockchain. Separate from the service key for security isolation. Stored at ~/.config/doublezero/metrics-publisher.json.
Hardware & Software
EOS (Extensible Operating System)
Arista's network operating system that runs on DZD switches. Contributors install Config Agent and Telemetry Agent as EOS extensions.
EOS Extension
A software package that can be installed on Arista EOS switches. DZ agents are distributed as .rpm files and installed via the extension command.