Verification before change
Network behaviour can be examined before configuration changes are applied in production.
Formal network verification builds a model from device configurations and uses it to analyse routing, traffic flow and the effect of access-control policy.
Pankkih helps identify the likely impact of a change before it is carried out on the live network. Practical network architecture and operations are covered on Network; the broader service description is on Services.
What can be checked?
- BGP routing policies, route filtering and route propagation
- Reachability between subnets, VLANs, VRFs and sites
- ACL and firewall policies
- Segmentation compliance
- Impact of configuration changes
- Possible traffic paths
- Reachability under node or link failure, where the model supports it
Practical example
Before a routing or firewall change, you can check whether a branch site still reaches data-centre services — and whether the same change would unintentionally allow traffic between otherwise isolated segments.
Comparing the current and proposed configurations highlights differences in reachability and in what traffic is permitted.
Technology
Batfish is an open-source network analysis and validation tool. It builds a model from device configurations and can be used to examine routing, traffic reachability, filtering rules and the effect of proposed changes.
Batfish supports several vendors, including Cisco, Juniper and Fortinet. Feature and syntax support vary by vendor and software release. MikroTik RouterOS should not be treated as fully supported. Devices outside tool support may need other analysis, model adaptation or a narrower scope.
Our contribution is the engineering around the tool: selecting which devices and policies to model, turning requirements into checks, interpreting the output and converting findings into concrete configuration changes and a clear report.
What you get
- Analysis of supported network configurations
- Formalisation of key reachability and segmentation requirements
- Check of the current state against those requirements
- Analysis of proposed changes on a test model
- Report of mismatches and potential regressions
- Recommendations for configuration fixes
Discuss network validation. Related: Network, Services, Expertise, Solutions. Public routing view: Looking Glass.