# Glossary and Terminology

**Last Updated:** 2025-01-20  
**Document Version:** 1.0  
**Status:** Active Documentation

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## Overview

This glossary provides definitions for terms, acronyms, and technical concepts used throughout the documentation.

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## A

### API (Application Programming Interface)
A set of protocols and tools for building software applications. In this context, refers to RPC APIs (ETH, NET, WEB3) exposed by Besu nodes.

### Archive Node
A blockchain node that stores the complete historical state of the blockchain, including all transactions and state changes. See also: Full Node, RPC Node.

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## B

### Besu
Hyperledger Besu, an Ethereum client used for running blockchain nodes. Supports both public and private networks, with features like permissioning and QBFT consensus.

### Block
A collection of transactions grouped together and added to the blockchain. In ChainID 138, blocks are produced approximately every 2 seconds using QBFT consensus.

### Blockscout
An open-source blockchain explorer that provides a web interface for viewing blockchain data, transactions, and smart contracts.

### Break-glass
Emergency access method that bypasses normal security controls. In this architecture, refers to optional inbound NAT rules for emergency access.

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## C

### CCIP (Chainlink Cross-Chain Interoperability Protocol)
A protocol for secure cross-chain communication and token transfers. The deployment includes Commit, Execute, and RMN node types.

### ChainID
A unique identifier for a blockchain network. ChainID 138 is the identifier for the Sankofa/Phoenix/PanTel network.

### cloudflared
The Cloudflare Tunnel client software that creates secure, encrypted connections between internal services and Cloudflare's edge network.

### Container (LXC)
Linux Container, a lightweight virtualization technology used by Proxmox. Containers share the host kernel but have isolated filesystems and network namespaces.

### CORS (Cross-Origin Resource Sharing)
A security feature that allows web applications to make requests to APIs from different domains. Configured in Besu RPC settings.

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## D

### DHCP (Dynamic Host Configuration Protocol)
A network protocol that automatically assigns IP addresses to devices on a network. Used for management VLAN (VLAN 11).

### DNS (Domain Name System)
A system that translates domain names (e.g., `rpc-http-pub.d-bis.org`) to IP addresses.

### DON (Decentralized Oracle Network)
A network of Chainlink nodes that work together to provide oracle services. In CCIP, there are Commit DONs and Execute DONs.

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## E

### Egress
Outbound network traffic leaving the internal network. Egress NAT pools map internal IPs to public IPs for allowlisting.

### Enode
Ethereum node identifier, a unique address that identifies a blockchain node on the network. Format: `enode://<node-id>@<ip>:<port>`

### ER605
TP-Link ER605 router, used as the edge router in this architecture. Two routers (ER605-A and ER605-B) provide redundancy.

### ES216G
TP-Link ES216G managed switch, used for network switching and VLAN trunking. Three switches provide core, compute, and management connectivity.

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## F

### Failover
Automatic switching to a backup system when the primary system fails. ER605 routers support WAN failover.

### Firewall
Network security system that controls incoming and outgoing network traffic based on predetermined security rules.

### Full Node
A blockchain node that stores the complete blockchain and validates all transactions. See also: Archive Node, RPC Node.

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## G

### Gateway
A network device that connects different networks and routes traffic between them. In this architecture, gateways are configured on ER605 routers for each VLAN.

### Genesis Block
The first block in a blockchain. The genesis block contains the initial configuration, including validators and network parameters.

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## H

### HA (High Availability)
System design that ensures services remain available even if individual components fail. ER605 routers provide active/standby redundancy.

### Hostname
A human-readable name assigned to a network device. In this architecture, hostnames follow patterns like `r630-01`, `ml110`, `besu-rpc-1`.

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## I

### Ingress
Inbound network traffic entering the internal network. In this architecture, ingress is primarily handled through Cloudflare tunnels.

### IPAM (IP Address Management)
The process of planning, tracking, and managing IP address space. This architecture uses deterministic IPAM aligned with VMID allocation.

### ISP (Internet Service Provider)
A company that provides internet access. This architecture uses Spectrum as the primary ISP, with a second ISP for failover.

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## J

### JWT (JSON Web Token)
A compact, URL-safe token format used for authentication. Besu RPC nodes use JWT tokens for secure API access.

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## L

### LXC (Linux Container)
See: Container

### Load Balancer
A device or service that distributes network traffic across multiple servers to improve performance and reliability.

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## M

### Mermaid
A text-based diagramming language used to create flowcharts, sequence diagrams, and other visualizations in markdown documents.

### ML110
HP ML110 Gen9 server, used as the management and bootstrap node in this architecture. IP: 192.168.11.10

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## N

### NAT (Network Address Translation)
A method of remapping IP addresses. In this architecture, NAT is used for egress traffic to map private IPs to public IPs for allowlisting.

### Nginx
A web server and reverse proxy. In this architecture, Nginx Proxy Manager (VMID 105) routes HTTP traffic to internal services.

### Node
A computer or virtual machine that participates in a network. In blockchain context, refers to Besu nodes (validators, sentries, RPC nodes).

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## O

### Omada
TP-Link's network management system. Used for managing ER605 routers and ES216G switches.

### Oracle
In blockchain context, a service that provides external data to smart contracts. Chainlink provides oracle services.

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## P

### P2P (Peer-to-Peer)
A network architecture where nodes communicate directly with each other without a central server. Blockchain networks use P2P for node communication.

### Permissioning
A feature that restricts which nodes can join a blockchain network. Besu supports node permissioning and account permissioning.

### Proxmox VE (Proxmox Virtual Environment)
An open-source server virtualization platform. Used to manage VMs and containers in this architecture.

### Public IP Block
A range of public IP addresses assigned by an ISP. This architecture uses 6× /28 blocks (16 IPs each) for different purposes.

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## Q

### QBFT (QBFT Consensus)
QBFT (QBFT Byzantine Fault Tolerance) is a consensus algorithm used by Besu for private/permissioned networks. Provides fast block times and finality.

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## R

### R630
Dell PowerEdge R630 server, used as compute nodes in the Proxmox cluster. Four R630 servers provide production compute capacity.

### RPC (Remote Procedure Call)
A protocol for requesting services from remote programs. Besu nodes expose RPC APIs (HTTP and WebSocket) for blockchain interactions.

### RMN (Risk Management Network)
A network of Chainlink nodes that provide security validation for CCIP operations. RMN nodes review and approve sensitive cross-chain operations.

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## S

### Sentry Node
A blockchain node that acts as a proxy between validator nodes and the public network, protecting validators from direct exposure.

### Sovereign Tenant
An isolated tenant environment with dedicated resources and network segmentation. This architecture supports multiple sovereign tenants (SMOM, ICCC, DBIS, Absolute Realms).

### Static Node
A hard-coded list of peer nodes that a blockchain node will always try to connect to. Used for reliable peer discovery in private networks.

### Subnet
A logical subdivision of an IP network. This architecture uses multiple subnets (one per VLAN) for network segmentation.

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## T

### TOML (Tom's Obvious Minimal Language)
A configuration file format. Besu uses TOML files for node configuration.

### Tunnel
An encrypted connection between networks. Cloudflare tunnels provide secure access to internal services without exposing public IPs.

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## V

### Validator
A blockchain node that participates in consensus by proposing and validating blocks. In QBFT, validators take turns proposing blocks.

### VLAN (Virtual Local Area Network)
A logical network segment that groups devices regardless of physical location. This architecture uses 19 VLANs for network segmentation.

### VMID (Virtual Machine ID)
A unique identifier assigned to each VM or container in Proxmox. This architecture uses a deterministic VMID allocation scheme (11,000 VMIDs).

### VM (Virtual Machine)
A software emulation of a physical computer. Proxmox supports both VMs (full virtualization) and containers (LXC).

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## W

### WebSocket
A communication protocol that provides full-duplex communication over a single TCP connection. Used for real-time RPC subscriptions.

### WAN (Wide Area Network)
A network that spans a large geographic area. In this architecture, WAN refers to internet connections on ER605 routers.

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## Related Documentation

- **[../02-architecture/NETWORK_ARCHITECTURE.md](../02-architecture/NETWORK_ARCHITECTURE.md)** ⭐⭐⭐ - Network architecture reference
- **[../06-besu/BESU_OFFICIAL_REFERENCE.md](../06-besu/BESU_OFFICIAL_REFERENCE.md)** ⭐ - Besu official documentation
- **[../07-ccip/CCIP_DEPLOYMENT_SPEC.md](../07-ccip/CCIP_DEPLOYMENT_SPEC.md)** ⭐⭐ - CCIP deployment specification

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**Last Updated:** 2025-01-20  
**Review Cycle:** Quarterly
