Email security and sender trust, together in one platform.
Opt-Inbox can simply be added to an existing email security stack to reduce clutter and distractions. Adopted as part of Sendio's ESG bundle to provide security and identity enforcement in one platform, simplify admin and queue management in a single pane, and reduce subscription costs and the number of vendors to manage.
Two questions. One control pane.
Reputable vendors do a good job at addressing email security, but most fall short in dealing with “safe” message desirability, resulting in delivering nuisance messages because they are safe, or withholding desirable messages because they might be spam.
Sendio’s ESG is designed with Opt-Inbox sender identity verification in mind. Bundled, they avoid false positives and overly aggressive ESG filtering, while Opt-Inbox eliminates clutter and distractions.
"Is this message dangerous?"
Sendio Email Security Gateway
Standards-based threat detection. SPF, DKIM, DMARC, IP reputation, behavioral analysis via Server Recon, multi-engine malware scanning. Reliable and proven, without claims of revolutionary superiority.
"Should this sender be allowed to interrupt?"
Sendio Opt-Inbox
Recipient-controlled sender verification. Deterministic decisions about who reaches the inbox. No probability scoring, no machine guessing. Each user owns their approved list.
Any reputable email security plus Opt-Inbox: Same outcome, different complexity
The two approaches below deliver identical recipient-controlled identity enforcement. The right choice depends on whether you prefer best-of-breed procurement or operational consolidation.
Sendio bundle: ESG + Opt-Inbox
Consolidate the vendor relationship and run a native two-layer architecture. ESG is designed with Opt-Inbox identity enforcement as an architectural assumption, not a retrofit.
- Single contract, single support contact
- Unified admin interface
- Native integration between security and identity
Any email security + Opt-Inbox
Keep your current email security vendor (Proofpoint, Mimecast, Microsoft 365, Barracuda, TrendMicro, Sophos, etc.) and add Opt-Inbox as the downstream identity layer. Best-of-breed approach, fully supported.
- No security vendor change required
- Add Opt-Inbox identity enforcement
- Mail flow rules between security and identity layers
Operational benefits, easier administration.
The Sendio bundle combines full email security protection with natively integrated sender identity verification.
Vendor consolidation
Single contract, single renewal cycle, lower costs, single support relationship. Reduce the number of vendor relationships your team manages.
Unified administration
Manage security policies and identity policies from one interface. No console switching, no separate dashboards, no fragmented audit trail, no need to chase internal designees for responsibility or action.
Native architecture
ESG is designed with Opt-Inbox as a downstream assumption. Security thresholds are tuned for the presence of identity enforcement rather than having to assume its absence, as standalone security platforms must.
Simplified operations
No manual coordination between separate security and identity systems. The two layers were designed to work together, so day-to-day operations are smoother.
Security decisions defer to sender identity.
Traditional security platforms make binary decisions without sender context, sometimes causing false positives. ESG performs all needed security checks before handing off the desirability question to Opt-Inbox, which means spam scoring and bulk handling can be more flexible (and more accurate) than they would be otherwise.
Sender identity state changes the disposition
The result: fewer false positives at the security layer, because borderline cases that would otherwise be quarantined are deferred to deterministic identity enforcement downstream.
Standards-based, AI facilitated, human controlled.
ESG implements the email security fundamentals reliably. When you want a single pane, it is a proven security solution that integrates natively with Opt‑Inbox identity enforcement.
Authentication enforcement
SPF, DKIM, and DMARC validation with configurable policy enforcement at the domain and group level.
Connection security
IP reputation filtering, DNS validation, and protocol enforcement at the SMTP layer.
Server Recon™
Behavioral reputation layer that monitors SMTP-level sender behavior for spam patterns and emerging threats. Sendio's signature contribution to the security stack.
Threat detection
Malware scanning, anti-virus and anti-spam, heuristic analysis for zero-hour threats, link inspection, and content filtering.
Policy management
Configurable disposition rules (quarantine, reject, defer) and a managed quarantine surface.
TLS encryption
Server-to-server encryption included by default. Email is encrypted from the moment it leaves Sendio's infrastructure to the moment it reaches the recipient's mail server.
Single pane. End-to-end visibility.
When you operate ESG and Opt-Inbox as a bundle, the administrative experience is meaningfully simpler than running two products from two vendors.
Manage both layers without console switching
Security policies (ESG) and identity policies (Opt-Inbox) configured from the same admin surface. No tab juggling, no context switching between disconnected dashboards.
Total filtering effectiveness in one dashboard
One report shows threats blocked (ESG) and unwanted senders held (Opt-Inbox). The combined view tells the complete story of what mail reached your team and what didn't.
Single provisioning workflow
Adding a user applies both security and identity configurations in one step. No double-entry, no risk of drift between systems.
Complete message journey, end to end
Track each message from arrival through ESG processing, through Opt-Inbox evaluation, to delivery. Troubleshoot disposition decisions without correlating logs across vendors.
Deploy how you need to.
Three deployment modes, identical product capabilities. The choice depends on your infrastructure preferences and regulatory requirements.
Cloud-hosted
Sendio manages infrastructure, updates, and scaling. Fastest deployment path with no infrastructure overhead on your side.
Virtual appliance
VM-based deployment for VMware or Hyper-V environments. Suitable for on-premises or air-gapped deployments where the appliance must live on your infrastructure.
Physical appliance
Dedicated hardware for high-volume mail flow or regulatory environments that require physical control of the security appliance.
Human agents only.
No automated responses, no chatbots, no AI-generated replies during business hours (9 AM - 8 PM ET, M-F). Every support interaction reaches a real engineer.
Sub-30-minute commitment
Human engineers respond to mail flow emergencies 24/7 with a sub-30-minute response commitment.
Always on monitoring
Sendio engineers monitor and address issues, generally before users experience disruption, and contact customer admins if action on their side is required.
Productivity improvement across deployments. Whichever path you choose.
Both deployment paths (existing security + Opt-Inbox, or the Sendio bundle) deliver the same identity enforcement and the same productivity gains. These ranges reflect observed results across customer organizations.
Kaspersky Workspace Spam Analysis (2022)
UC Irvine interruption research
Sendio Telemetry
Kaspersky Workspace Spam Analysis (2022)
UC Irvine interruption research
Sendio Telemetry
The bundle, explained.
Is ESG required to use Opt-Inbox?
Why would I choose the bundle over keeping my existing security?
Is ESG better at threat detection than Proofpoint or Mimecast?
What does "native two-layer architecture" actually mean in practice?
Can I migrate to the bundle from a third-party security platform later?
What deployment options are available?
What does support look like?
What's the guarantee?
One vendor, two layers, same outcomes.
Schedule a 30-minute walkthrough to see ESG and Opt-Inbox running as a native bundle. We'll cover the architecture, the deployment options for your environment, and the practical differences from your current setup.