Status: Open. RFI responses due Friday, November 13, 2026, by email to FastVacc@darpa.mil. The RFI document says 5:00 PM ET and SAM.gov lists 12:00 PM ET, so plan for noon. This is a Request for Information, not a funding solicitation.
Executive Summary
DARPA's Information Processing Techniques Office (IPTO) wants ideas for cutting the time and cost of network security compliance checking by 100 to 1,000 times, starting from natural-language requirements and real network configurations. Companies, universities and labs can respond with a one-page narrative and two slides by November 13, 2026.
The RFI offers no funding and is not a solicitation, but it shapes what DARPA may fund next. BW&CO estimates that a follow-on DARPA project in this area would likely run about $1M a year. DARPA has not posted any amount.
Solicitation at a Glance
- Agency: Defense Advanced Research Projects Agency (DARPA), Information Processing Techniques Office (IPTO)
- Notice: Special Notice DARPA-SN-27-13, Request for Information
- Title: Verification and Compliance Checking for Natural-Language Network Requirements (FastVacc)
- Posted: October 29, 2026
- Funding: None. RFI only, and DARPA does not reimburse response costs. BW&CO estimate for a follow-on project: about $1M a year (not a DARPA figure).
- Response: One-page narrative and up to two slides, one with DARPA's Table 1
- Due Date: Friday, November 13, 2026 (5:00 PM ET in the RFI document; 12:00 PM ET on SAM.gov)
- Classification: Unclassified responses only
Think your company qualifies? Talk with BW&CO before the November 13 deadline.
What Is FastVacc?
FastVacc is DARPA's name for a capability that would take two inputs: a requirements document written in natural language and the configurations of a real network. Offline, it would find inconsistent, redundant and incomplete requirements and output a consistent, completed set. Then it would check in near real time whether the network's configurations satisfy every requirement, with output a person can understand.
What Problem Is DARPA Trying to Solve?
Networks must be reconfigured quickly when missions change or threats emerge, but checking compliance with security requirements can take months. That gap gives adversaries time to exploit new vulnerabilities. Today analysts read documents such as NSA Commercial Solutions for Classified (CSfC) capability packages, zero trust architecture guidance (NIST SP 800-207) and NIST SP 800-53 system and communications protection controls, interpret them by hand, and test only a sample of cases.
Priority Capability Areas: What DARPA Is Asking About
- Natural language understanding: Requirements documents run hundreds of pages, reference other documents and use mission-specific abstractions, such as encryption gateways or policy enforcement points, that must be found in unlabeled configurations.
- Reasoning: Detecting contradictory, redundant or incomplete requirements at scale, and extending requirements when an architecture adds high availability, failover or performance features.
- Evaluation: Checking every instance of a requirement across firewalls, flows, gateways and paths instead of a sample, and translating requirements into network verification tool queries.
- Beyond a language model: Whether uploading a document and a configuration to a large language model is enough, or whether an intermediate formal system or domain-specific language is needed.
- A "Netlib" for networking: Whether a growing library of formalized network properties, like Lean's Mathlib for math, could work.
- Metrics, data and risks: How to measure translation fidelity, reasoning quality and compliance accuracy, what datasets exist, and which current technologies solve parts of the problem.
Funding
This RFI offers no funding, is not a solicitation for abstracts or proposals, and DARPA will not reimburse response costs. Any abstract or proposal sent against it will be disregarded. BW&CO estimates that a follow-on DARPA project, if DARPA launches a program, would likely run about $1M a year. That is BW&CO's estimate, not a DARPA figure.
Eligibility Requirements
- Who can respond: Companies, individuals, universities, university-affiliated research centers, nonprofit research institutions and U.S. Government-sponsored labs.
- Classification: Unclassified responses only.
- Proprietary information: Submit non-proprietary information where possible, and label anything proprietary as "Proprietary."
How to Respond
- Choose which of DARPA's seven questions your team answers best. You do not have to answer all of them.
- Write a one-page narrative and up to two slides. One slide must include DARPA's Table 1, covering how each problem is solved today, its limits, what is new in your approach and the strategic surprise, for natural language understanding, reasoning and evaluation.
- Include your organization name and a technical point of contact with email and phone.
- Format as unprotected Word, PowerPoint or PDF files in English, on 8.5 x 11 inch pages with 1-inch margins and 12-point font or larger (8 or 10 point allowed in figures and tables).
- Email FastVacc@darpa.mil by November 13, 2026, and send questions to the same address citing DARPA-SN-27-13.
What Happens After You Submit?
- Follow-up: DARPA may contact respondents to clarify or discuss technical information.
- No obligation: DARPA does not have to acknowledge receipt, invite respondents to events or give feedback.
- Next step: Watch SAM.gov for any follow-on program announcement. New to DARPA? The RFI points to DARPAConnect for free resources and one-on-one conversations.
Is This Opportunity a Good Fit for Your Company?
It fits companies working on network verification, formal methods, policy-as-code, configuration analysis or language models applied to security requirements, especially teams that know CSfC, zero trust or NIST SP 800-53 compliance. A response is short, so it also suits teams that want IPTO to know their approach before a program exists.
How BW&CO Can Help
BW&CO has helped deep-tech and dual-use founders secure more than $350M in non-dilutive funding. For DARPA RFIs like FastVacc, we help you:
- Connect with the right DARPA program manager before you respond, where we can.
- Choose which of DARPA's seven questions to answer.
- Write the one-page narrative and build the Table 1 slide.
- Position the response for a possible follow-on solicitation.
- Plan the proposal if DARPA launches a program.
Plan Your FastVacc RFI Response
Frequently Asked Questions
When is it due?
Friday, November 13, 2026. The RFI document says 5:00 PM ET and SAM.gov lists 12:00 PM ET, so plan to send it by noon.
Is there funding?
No. This is a Request for Information. DARPA will not pay for responses, and abstracts or proposals sent against it are disregarded.
How big could a follow-on project be?
DARPA has not posted any amount. BW&CO estimates that a follow-on DARPA project in this area would likely run about $1M a year.
Who can respond?
Companies, individuals, universities, university-affiliated research centers, nonprofit research institutions and U.S. Government-sponsored labs.
What should a response look like?
A one-page narrative and up to two slides, with one slide showing DARPA's Table 1, sent as unprotected Word, PowerPoint or PDF files.
Can I include proprietary information?
DARPA asks for non-proprietary information where possible. Label anything proprietary as "Proprietary," not "Confidential."
Do I have to answer every question?
No. DARPA invites responses to any of its seven questions.
Will DARPA reply?
DARPA may reach out to discuss technical points but is not obligated to acknowledge or give feedback.
Can BW&CO help with a FastVacc response?
Yes. BW&CO can help you reach the right DARPA program manager, choose the questions to answer and write a response that positions you for a follow-on. Book a call with our team.
Source: SAM.gov: DARPA-SN-27-13, FastVacc Request for Information