Cisco Secure Email Threat Defense is a commercial email security platforms solution by Cisco. Microsoft Exchange 2019 Transport Filtering Agent is a free email security platforms solution. Features, integrations, deployment and the company behind each one, side by side.
What our shortlists say about the one we picked.
Best for: Cisco shops wanting Talos-backed filtering
It is on the list as a Microsoft 365 product that can grow with you: you start in API mode and add the inline gateway later, from the same console. That suits a team that already runs Cisco security. Check fit first if you run Google Workspace or your own mail servers, because the product is built for Microsoft 365.
From Best Email Security Solutions for Business, Fall 2026
Reviewed by Nika (Nikoloz) Kokhreidze.
Email threat protection for Microsoft 365 with advanced detection capabilities
Detects and handles potential malware in Microsoft Exchange 2019 messages with various techniques and third-party libraries.
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Based on what each listing shows: deployment, company size, price and open source.
Cisco Secure Email Threat Defense fits if you want a cloud product.
Microsoft Exchange 2019 Transport Filtering Agent fits if you need to run it on your own servers, you need a free product and you want an open-source product.
Common questions when comparing Cisco Secure Email Threat Defense vs Microsoft Exchange 2019 Transport Filtering Agent for email security platforms.
Cisco Secure Email Threat Defense: Email threat protection for Microsoft 365 with advanced detection capabilities. Built by Cisco.
Microsoft Exchange 2019 Transport Filtering Agent: Detects and handles potential malware in Microsoft Exchange 2019 messages with various techniques and third-party libraries.
The table above shows where their features, integrations, deployment and company size fit differ.
Cisco Secure Email Threat Defense is made by Cisco. Microsoft Exchange 2019 Transport Filtering Agent is open-source with 20 GitHub stars. The vendor behind a product decides its roadmap, support, and longevity, so check each company's profile before you commit.
Often, yes. Cisco Secure Email Threat Defense and Microsoft Exchange 2019 Transport Filtering Agent are both Email Security Platforms products. Key differences: Cisco Secure Email Threat Defense is Commercial while Microsoft Exchange 2019 Transport Filtering Agent is Free, Microsoft Exchange 2019 Transport Filtering Agent is open-source. Use the table above to see where features, deployment and company size fit differ.
Need the answer fast? Best Email Security Solutions for Business picks Proofpoint Core Email Protection, Microsoft Defender for Office 365, Mimecast Advanced Email Security and 4 more.See the shortlist
