This is the part I'm still figuring out. If we build custom alerts on their specific schema, how do we even know what we're agreeing to? Their mapping doc might list fields, but does that mean their backend actually treats those fields the same way a SIEM would for correlation?
That's a great idea about pushing for a *billing sandbox*. I hadn't thought to ask for that, I just assumed they'd show generic demos. But you're right, if they can't show you your specific logic in a test setup, it's a huge risk.
Does asking for that sandbox usually work? Or do vendors see it as too much work for a potential sale?
Oh wow, I hadn't even considered the vendor lock-in part. That's a huge point. Once you've customized all your alerts around their specific Sysmon integration, moving to another EDR sounds like a nightmare. Are there any standards for how this data is structured, or is every vendor completely different?
No, there are no standards. They'll give you a mapping doc, but it's a proprietary internal schema. Once you write detections against those fields, you're married to them.
It's worse than you think. They'll sometimes silently remap fields between versions during backend updates. Your custom logic breaks, and you'll spend weeks in support tickets proving it's not your config.
Prove it.
Absolutely nailed the procurement angle. That 20% figure is optimistic if you're not filtering. I watched a team turn on a broad Sysmon feed for "better visibility" and their EPS basically doubled overnight. The shock wasn't just the bill, it was hitting a performance cap that caused event loss.
Your point about validating the detection logic is key. A lot of vendors will happily take the data but their out-of-the-box rules never query it. You're just paying to build their data moat.
dk
Good point about pushing the TAM to differentiate between processed and ingested data. The really tricky part is when they offer unlimited ingestion but attach a separate fee per "queryable data unit" or something similar a few months in.
My own rule is to get it in the form of an amended contract addendum, not a statement of work or a support ticket. Procurement respects the contract, everything else is a conversation.
—daniel
Completely agree on needing that formal TAM statement, but I'd push further. You have to get the promised detection use cases in writing, with the specific Sysmon field names listed. I've seen that promise turn into "we support the data" which just means they'll store it. Their default correlation rules never touch the new fields, leaving you with a cost hike and zero new alerts.
The procurement angle is critical. Don't just review the license, you need to ask about their internal data lifecycle and any hidden reclassification. Some vendors will silently move your ingested data to a colder, slower query tier after 30 days unless you pay for a "performance add-on." That detail is never in the standard ingestion clause.
Logs don't lie.
You're right about the detection use cases. I ran a benchmark once where we compared alert generation with and without the promised Sysmon fields. The vendor's "supported" fields were there in the schema, but their default rule engine literally had zero queries referencing them. We only caught it because we built identical test logic in a separate sandbox and compared outputs.
That colder tier trick is real. Had a client get hit with a 40% query performance drop after their "30-day hot retention" period. The vendor's response? "Your queries are now accessing archived data, upgrade to our performance tier." It was buried in a data management doc, not the sales contract.
So it's not just that we'd be locked into the vendor, but locked into their *specific version* of that data? That's somehow worse.
I get why they'd want to remap fields internally, but breaking existing custom alerts without notice is a scary prospect. Is there any way to test for that before committing, like asking them to document the last time a schema change broke customer logic? Or do they just see that as confrontational?
Just my two cents.
That version-lock is exactly what worries me. Asking about past breakage might not seem confrontational if you frame it as due diligence for your own change control process.
Do you think they'd even share that kind of history? Feels like something they'd call internal.
Still learning.
They'll call it proprietary, sure. But ask anyway, and watch the account team squirm. That squirming is your data point.
I've framed it as "We need to understand your deprecation policy for custom field mappings to comply with our internal audit controls." Sometimes you get a vague PDF, sometimes they stop responding. Either way you know what you're dealing with.
Trust but verify.
You're spot on about the cost creep. That 20% figure is something I've seen hit HR tech budgets, too, when teams get excited about piping custom engagement survey data into fancy analytics platforms.
The "validating detection logic" angle is crucial. In my world, it's like buying a new performance module that promises to "ingest" peer feedback data, but then its pre-built review templates never actually pull from that new source. You've paid for a connector, not a real feature.
Getting that formal TAM statement is the only safe move. Did your team ever try to negotiate a clause that ties cost increases to a proven alert improvement metric? Just curious.
You're right about the license agreement check, but that's step one of a two-step trap. Even if the ingestion clause seems clear, the real cost often comes from their definition of "processed" versus "queried."
You can have a contract that says unlimited ingestion, only to find your queries hitting a separate compute cost because they've moved your enriched data into a "premium analytics tier" at the backend. I've seen teams get a green light from legal on the data volume, then get a six-figure surprise from the "advanced query pack" needed to actually use the Sysmon fields in dashboards.
So it's not just about paying for the data to sit there, it's paying for the privilege to ask it a question. Did your review catch any language segregating storage costs from query compute? That's where the 20% estimate usually dies.
Data skeptic, not a data cynic.
You're asking how teams track that overhead? They don't. That's the point.
It's not tracked, it's absorbed. It vanishes into the morass of "security operations" as just another recurring, unmeasured tax. The admin time gets buried, the security benefit is a vague feeling of slightly better coverage, and the cost only surfaces when you try to automate it and need a developer for three sprints to codify all the exclusions.
My cynical take is that quantifying it would reveal the whole exercise as a net negative for most shops, which is why nobody does the math.
FOSS advocate
That's precisely why it pays to instrument the enrichment pipeline itself, not just the endpoint data. We added lightweight metrics at each transformation stage - sysmon parsing, field mapping, rule execution - and graphed the ratio of enriched events that actually fired a net-new detection. The "security benefit" went from a vague feeling to a hard percentage.
In our case, that number was under 5% for the first six months. It forced a hard conversation about whether we were building a detection system or just a very expensive archive of "potential" context.
The developer sprint cost to codify exclusions isn't a bug, it's the final, unavoidable price tag that proves the value was never in the raw data feed itself.
throughput first