My results after 6 months: Cato cut our MPLS bill but added cloud surprise fees.

After a six-month evaluation period migrating from a traditional MPLS WAN to Cato's SASE platform, I can confirm the core financial hypothesis: a drastic reduction in carrier circuit costs. However, the total cost of ownership narrative requires significant nuance. Our initial projection showed a 62% reduction in our global MPLS and internet breakout expenditures, which has largely materialized. The operational simplification of managing a single, global policy set across 47 sites is not insignificant.

The primary unforeseen cost vector emerged from cloud application traffic, specifically the egress fees incurred from major cloud providers (AWS, Azure, GCP). Our legacy architecture used direct internet breakouts at regional hubs, which, while inefficient from a security perspective, did not traverse the Cato backbone for cloud-destined traffic. Post-migration, all traffic is backhauled to the nearest Cato PoP for inspection.

### The Financial Breakdown

* **MPLS/ISP Savings:** $28,500/month reduction. This is clear and realized.
* **Cato Base Subscription:** $12,200/month. Aligns with initial quote.
* **Cloud Egress Overages:** Average $4,750/month. This was the surprise.

The cloud cost arises because traffic from a branch to, for example, an AWS S3 bucket in `us-east-1`, now follows this path: Branch -> Cato PoP (inspection) -> AWS `us-east-1`. The leg from the Cato PoP to AWS is now a distinct cloud egress transaction, billed by the cloud provider. While Cato provides excellent visibility, it did not inherently change our cloud egress volume.

### Technical Configuration & Observation

We attempted to implement a "Local Internet Breakout" policy for trusted cloud IP ranges to mitigate this. The complexity, however, lies in maintaining an accurate, dynamic allow-list of SaaS and IaaS provider IPs, which introduces operational overhead and potential security drift.

```hcl
# Example Terraform snippet for a Cato Sockets configuration attempting local breakout
# This becomes a maintenance burden.
resource "cato_socket" "branch_office_1" {
name = "branch-office-1"
...
}

resource "cato_network_rules_policy" "cloud_breakout" {
name = "selective-cloud-breakout"
rule {
name = "allow-aws-us-east-1"
sources = [cato_socket.branch_office_1.id]
# Destination is a manually managed CIDR list
destinations = ["52.0.0.0/10", "54.0.0.0/10"]
action = "ALLOW"
# Bypasses Cato backbone for these destinations
routing_options = "LOCAL"
}
}
```

### Conclusion and Recommendations

Cato delivers on its promise of network consolidation and security integration, but the financial model must be analyzed through a FinOps lens. Organizations considering this migration should:

* Conduct a detailed traffic analysis prior to migration, specifically categorizing cloud and SaaS destination traffic volumes.
* Model the cloud egress costs based on the locations of your Cato PoPs relative to your primary cloud regions.
* Factor in the operational cost of maintaining and auditing dynamic breakout policies if you choose to implement them as a mitigation strategy.

The outcome is positive from a security and MPLS cost perspective, but the shift from a fixed-cost carrier model to a variable-cost cloud egress model must be actively managed. The true value will depend on whether the enhanced security posture and operational simplicity offset this newfound cloud cost variability.