.TEL Directory Infrastructure for Agent Discovery & Communication – Citation-Quality Ontology Schema
✓ 76% Tier-1 SourcesThis ontology provides authoritative definitions for .TEL-specific directory services enabling AI agent contact information and communication endpoints. The .TEL TLD specializes in real-time contact data enabling direct agent-to-agent communication initiation through DNS-based storage.
Coverage: .TEL DNS architecture, NAPTR contact records, SIP/VoIP integration, ENUM mapping, presence indicators, multi-protocol endpoints, GeoDNS routing, contact verification, and privacy controls.
Specialized top-level domain designed for storing contact information directly in DNS NAPTR records rather than traditional web hosting. Each .TEL domain functions as distributed contact database enabling instant resolution without intermediate servers. For AI agents, .TEL provides standardized contact endpoint storage including HTTP URLs, WebSocket addresses, gRPC endpoints, and protocol-specific connection strings accessible via standard DNS queries. DNS-based storage enables zero-configuration discovery where clients query domain receiving all contact methods in single response.
Structured connection information enabling agent communication including primary invocation URL (RESTful HTTP endpoint), WebSocket URL for bidirectional streaming, gRPC service address for type-safe RPC, MQTT broker for message queue integration, and authentication endpoint. HTTP Discovery Protocol specifies unified invocation interface accepting standardized request format returning JSON responses with operation results and metadata. Endpoints stored in .TEL NAPTR records enable clients to discover all communication methods through single DNS lookup.
Telephone Number Mapping protocol enabling agents to use E.164 telephone number format for addressing. AgentDNS service identifier agentdns://{organization}/{category}/{name} can map to ENUM-style +1-555-AGENT format facilitating telephony-integrated workflows. Particularly relevant for voice-capable AI agents interfacing with traditional phone systems, enabling seamless bridge between internet-based agent communication and PSTN infrastructure. ENUM lookups translate telephone numbers to URIs stored in DNS NAPTR records.
Dynamic DNS update mechanism allowing agents to modify contact endpoints without domain transfer. .TEL domains support programmatic updates via DNS UPDATE protocol enabling agents to advertise endpoint changes, capability additions, or temporary unavailability in real-time. Critical for mobile agents changing network locations, load-balanced deployments rotating endpoints, or services transitioning between protocol versions. Updates propagate through DNS hierarchy typically within minutes enabling responsive contact management.
Agent Networks Framework defines presence as real-time availability status including online/offline state, current workload capacity, response time estimates, and temporary unavailability periods. Stored as DNS TXT records in .TEL domain enabling lightweight polling without establishing full connection. Presence-aware discovery allows clients to preferentially contact available agents, implement failover to backup agents, or queue requests during maintenance windows. Presence data may include capacity percentage (0-100), expected response latency, and scheduled downtime windows.
Session Initiation Protocol adaptation for AI agent communication enabling voice-capable agents to participate in telephony workflows. SIP URIs stored in .TEL NAPTR records (sip:[email protected]) facilitate click-to-call functionality, conference participation, and voicemail systems. Particularly relevant for customer service agents, voice assistants, and real-time translation agents requiring audio stream processing. SIP integration enables agents to join traditional phone conferences, receive voicemail messages, and handle call routing.
.TEL domains store comprehensive protocol support matrix indicating which communication standards agent implements. Contact card includes HTTP/1.1 or HTTP/2 support, WebSocket availability, gRPC service definitions, MQTT topic subscriptions, and proprietary protocol endpoints. Enables clients to select optimal communication method based on network conditions, required features (streaming vs request-response), and client capabilities. Protocol negotiation occurs during discovery phase before establishing actual connection.
HTTP Discovery Protocol specifies authentication methods stored in agent metadata including OAuth 2.0 (client credentials or authorization code flow), API key authentication via header or query parameter, mTLS client certificates, JWT bearer tokens, or no authentication for public agents. .TEL contact record includes authentication endpoint URL, supported methods, and token request procedures enabling automated credential acquisition. Authentication metadata prevents unauthorized access while supporting various security models from open public agents to enterprise-grade secured agents.
DNS Service Discovery extension enabling zero-configuration agent discovery on local networks. Agents advertise services via multicast DNS (mDNS) announcing capabilities, endpoints, and availability. Complements global .TEL registry with local discovery for enterprise deployments, edge computing scenarios, or air-gapped networks. Follows RFC 6763 DNS-SD standard adapted for agent-specific service types. Local discovery enables agents to find each other within organizational boundaries without requiring internet connectivity or central registry access.
Redundant contact information ensuring agent reachability despite endpoint failures. .TEL records include primary endpoint, secondary endpoint for failover, tertiary endpoint for disaster recovery, contact email for async communication, and status page URL. Agent Networks Framework specifies failover logic: attempt primary with timeout, switch to secondary if unavailable, escalate to human operator if all endpoints fail. Fallback mechanisms critical for high-availability agents supporting production workloads.
Periodic testing ensuring advertised endpoints remain reachable. Registry performs health checks against HTTP endpoints expecting 200 OK responses, WebSocket connection establishment tests, gRPC service reflection queries verifying available methods, and MQTT subscription confirmation. Failed health checks trigger contact owner notification, endpoint status updates in directory, and eventual removal if persistently unavailable. Verification intervals typically range from 5 minutes for critical agents to 24 hours for stable services.
Standard DNS records adapted for agent contact storage including NAPTR records for URI mapping (service type, protocol, endpoint URL), SRV records for service location (port, priority, weight), TXT records for metadata (protocol versions, authentication requirements, capabilities), A/AAAA records for direct IP addressing when applicable, and CAA records specifying authorized certificate authorities. Enables standard DNS tools to query agent contact information without specialized software.
GeoDNS-based endpoint selection returning nearest agent instance based on client location. .TEL domain configured with multiple A records each representing different geographic region (US-East, EU-West, APAC). DNS server returns record set ordered by proximity reducing latency for global agent deployments. Particularly important for latency-sensitive applications like real-time translation or financial trading agents. GeoDNS can reduce round-trip time from 200ms+ cross-continent to 20ms regional improving responsiveness.
Selective disclosure enabling agents to expose different contact details based on requester identity. Public directory shows limited contact (general inquiry endpoint), authenticated partners see full endpoints (WebSocket, gRPC), verified enterprise clients receive priority contact channels (dedicated queue endpoints, SLA-backed response guarantees). Implemented via DNS views returning different record sets based on query source or authentication-gated registry APIs requiring credentials before exposing sensitive endpoints.
ADS specification supports bulk retrieval of agent contacts for offline processing, caching, or integration with enterprise directories. DHT-based distribution enables efficient bulk download without overwhelming single registry server. Export formats include CSV for spreadsheet import, vCard for contact management systems, JSON for programmatic processing, and LDIF for LDAP directory integration. Enables hybrid online/offline agent discovery where organizations maintain local cache updated periodically from global registry reducing dependency on real-time DNS queries.