SMTP Compatible
Works with standard SMTP mail servers and messaging infrastructures.
Bardin Gate Mail Gateway
Air-Gapped Email Transfer
Transfer SMTP messages across physically separated networks through a controlled and isolated communication path.
Source Mail Server
SMTP messages are submitted from the source mail environment.
Bardin Gate Mail Gateway
Messages are queued, transferred, and delivered across the air-gapped communication path.
Destination Mail Server
Messages are delivered using standard SMTP protocols.
Air-Gapped SMTP Relay
Email Communication Across Isolated Networks
Bardin Gate Mail Gateway enables reliable SMTP communication between physically separated environments while preserving network isolation.
Air-Gapped Communication
Enable email exchange across separated environments without direct network connectivity.
One-Way or Two-Way Transfer
Support both unidirectional and bidirectional communication models.
Infrastructure Transparency
Operates as a standard SMTP relay without requiring changes to existing email workflows.
Transport-Only by Design
Bardin Gate Mail Gateway is designed as an SMTP transport appliance. It does not act as a mail security gateway, content inspection system, DLP, anti-spam engine, or policy review workflow.
No DLP
The product is not positioned as a data loss prevention engine.
No Anti-Spam
It is not designed to classify, block, or score unwanted email.
No Content Inspection
It does not analyze message content as a mail security product.
SMTP Transport
Its role is message transfer between separated SMTP environments.
Message Transfer Workflow
Mail Gateway focuses on reliable message transportation between isolated environments.
1. Receive
Receive SMTP messages from the source mail server.
2. Queue
Store and manage messages inside the transfer appliance.
3. Transfer
Move messages across the isolated communication path.
4. Deliver
Deliver messages to the destination SMTP server.
5. Track
Monitor transfer status and delivery outcomes.
6. Audit
Maintain transfer logs and operational records.
Key Capabilities
Built specifically for SMTP communication across isolated and air-gapped environments.
SMTP Relay
Standards-based SMTP message transport.
Message Queueing
Reliable message handling and delivery management.
Audit Logs
Visibility into message transfer operations.
High Availability
Support resilient enterprise deployment architectures.
Flexible Direction
One-way or bidirectional SMTP communication models.
Mail Server Agnostic
Compatible with common enterprise mail platforms.
Air-Gapped Transfer
Designed for physically separated environments.
Delivery Tracking
Visibility into transfer and delivery status.
Communication Direction Models
The gateway can support communication patterns based on the organization’s air-gap and operational requirements.
One-Way Transfer
SMTP messages flow from one network toward another controlled destination.
Reverse Direction
Message flow can be configured in the reverse direction when required.
Bidirectional Transfer
Two-way SMTP communication can be supported through controlled transfer paths.
Common Use Cases
Email communication across environments where direct connectivity is restricted or unavailable.
Government Networks
SMTP communication between separated government or sensitive environments.
Critical Infrastructure
Operational email transfer across isolated infrastructure zones.
Defense Environments
SMTP relay across separated mission or security domains.
Telecom Operators
Message transfer between operational, support, and enterprise domains.
Financial Organizations
Controlled SMTP communication between segregated environments.
Industrial and OT Networks
Email transfer between enterprise and operational technology zones.
Need SMTP Communication Across an Air Gap?
Talk to Bardin Tech about your mail servers, communication direction, isolation model, and deployment requirements.