Evaluating an LI mediation platform requires asking the right technical and commercial questions. The mediation platform is the engine of your lawful interception system. It turns the X2/X3 records from the points of interception into the national HI2/HI3 handover formats and manages delivery of intercepted material to law enforcement, under the control of the administration function (LIMS/ADMF) through which your team manages active interceptions. Choosing the right mediation platform is one of the most important procurement decisions in the LI domain, and making the wrong choice can result in compliance gaps, operational inefficiencies, and costly replacements.
Yet evaluating mediation platforms is not straightforward. The LI market is specialised, vendor claims can be difficult to verify independently, and the technical requirements are complex. To help operators navigate this process, this article presents seven essential questions that should form the core of any mediation platform evaluation. These questions are designed to reveal the true capabilities, limitations, and suitability of a vendor’s offering — and to help you distinguish between genuine capability and marketing claims.
1. Which National Interface Specifications Do You Support?
ETSI compliance is the baseline, but it is not sufficient. Every European country layers national-specific requirements on top of the ETSI standards. Germany has the TKÜV and TR TKÜV specifications. The Netherlands has the ETSI-IP.nl profile. France has the requirements for delivery to the judicial platform (PNIJ) and to the GIC. Austria has national profiles of the ETSI handover (AK-TK EP 023), plus the BRZ-run Durchlaufstelle for data disclosure requests. And so on for every market where you operate or plan to operate. A mediation platform that supports generic ETSI handover but cannot implement the specific national interface will fail in practice.
When evaluating a vendor, ask specifically which national interface specifications are supported and verified through testing with the relevant national authority or LEMF. Request evidence of successful interoperability testing — not just claims of compliance, but documented test results or reference deployments. If you operate in multiple markets, evaluate whether the platform can support multiple national interfaces simultaneously, as this is a common requirement for operators with a pan-European presence.
This question also reveals the vendor’s commitment to ongoing compliance. National interface specifications evolve, and the vendor must demonstrate a track record of updating their platform to keep pace with regulatory changes. Ask about the vendor’s process for monitoring and implementing specification updates, and about the typical timeframe from specification change to platform update.
2. What Network Technologies and Equipment Vendors Are Supported?
The mediation platform must interface with your network infrastructure to receive intercepted data from the points of interception in your network, over the standard X2/X3 interfaces (ETSI TS 103 221-2) where the equipment supports them and over vendor-specific formats where it does not. This means that the platform must support the X2/X3 records and the national handover formats for every service in your network (2G, 3G, 4G, 5G, IMS, Wi-Fi calling and any others), and must interoperate with the X2/X3 implementations of your equipment vendors.
Multi-vendor support still matters, but for mediation it is a question of standards conformance, not per-vendor adaptors: network functions from different vendors deliver over the same X2/X3 protocol. Ask which legacy proprietary interfaces, if any, the platform still supports. Ask the vendor for a list of validated integrations with specific network equipment vendors and product versions. Pay particular attention to 5G support, including the X1/X2/X3 interfaces (ETSI TS 103 221-1/-2, as profiled in 3GPP TS 33.128), and verify that the vendor has tested these integrations in production or pre-production environments.
Also consider future network evolution. If you plan to deploy new technologies — such as 5G SA, network slicing, or edge computing — evaluate whether the mediation platform has a roadmap for supporting these technologies and whether the vendor has the engineering capability to deliver on that roadmap.
3. How Does the Platform Handle Concurrent Intercepts at Scale?
Scalability is a fundamental requirement, but it is also an area where vendor claims can be misleading. Ask the vendor to specify the maximum number of concurrent intercepts the platform supports, along with the conditions under which that number is achievable. The answer should include details about the mix of interception types (voice, data, SMS), the volume of IRI events and CC data generated, and the number of simultaneous LEMF delivery connections.
Performance under load is as important as peak capacity. Ask how the platform performs when operating at or near its capacity limits. Does it degrade gracefully, or does it fail abruptly? What monitoring and alerting mechanisms are in place to warn operators when capacity limits are approaching? Can additional capacity be added without downtime or disruption to active intercepts?
Request performance test results or benchmark data that demonstrate the platform’s scalability claims. If possible, include scalability testing as part of your evaluation process, using realistic traffic profiles and interception scenarios that reflect your operational environment.
4. What Security Certifications and Features Does the Platform Offer?
The mediation platform handles some of the most sensitive data in your entire infrastructure. The security features of the platform are therefore critical to your compliance posture and to the protection of intercepted material. Ask the vendor about the platform’s security architecture, including encryption of data at rest and in transit, access control mechanisms, audit logging capabilities, certificate management, and secure key storage.
Inquire about security certifications or independent assessments. Has the platform undergone a security audit by an independent third party? Does the vendor hold relevant security certifications such as ISO 27001 or Common Criteria? Are penetration tests conducted regularly, and are the results available to customers?
Role-based access control (RBAC) should be granular, supporting the separation of duties between warrant management, operations, and audit functions. Multi-factor authentication should be supported for all access to the platform. The audit log should be tamper-evident and should capture all user actions, system events, and configuration changes with sufficient detail to support regulatory review.
5. What Is Your Deployment Model — On-Premises, Cloud, or Hybrid?
The deployment model of the mediation platform has significant implications for security, performance, operational management, and cost. Ask the vendor what deployment options are available — on-premises physical appliance, virtualised deployment on the operator’s infrastructure, private cloud, public cloud, or hybrid models — and what the trade-offs are between each option.
For many operators, on-premises deployment in a dedicated, physically secured environment remains the preferred model for LI, given the sensitivity of the data involved. However, virtualised and cloud-native deployments offer advantages in terms of scalability, resilience, and operational efficiency. If the vendor offers cloud or virtualised deployment, ask about the specific security measures in place to protect intercepted data in these environments, including hypervisor isolation, container security, network segmentation, and compliance with relevant data sovereignty requirements. Check national location rules (Germany, for example, requires the systems that control the interception functions and the handover point to be operated in Germany (§ 14(1) TKÜV)) and ask whether the virtualised deployment meets ETSI GS NFV-SEC 012, as 3GPP TS 33.126 requires.
Containerised and Kubernetes-native deployments are increasingly relevant for operators running cloud-native 5G networks. Evaluate whether the platform supports these deployment models and whether the vendor has validated the platform in containerised environments with production-representative workloads.
6. What Are Your Support and Maintenance Commitments?
The mediation platform is a critical system that requires ongoing support, maintenance, and updates. Ask the vendor about their support model, including available support tiers, response times for different severity levels, escalation procedures, and the availability of on-site support if required. The LI system operates continuously, and support must be available around the clock for critical issues.
Maintenance and update procedures are equally important. How frequently are software updates released? How are updates tested and validated before deployment? Can updates be applied without interrupting active interceptions? What is the vendor’s process for delivering urgent security patches?
Standards updates represent a specific maintenance requirement. As ETSI, 3GPP, and national specifications evolve, the platform must be updated to remain compliant. Ask about the vendor’s track record for delivering standards updates in a timely manner and about the typical lead time between a specification change and the corresponding platform update.
7. Can You Provide Reference Deployments in Comparable Environments?
Reference deployments are one of the most valuable sources of information in a mediation platform evaluation. Ask the vendor to provide references from operators with comparable network architectures, subscriber bases, and regulatory environments. Ideally, these should be operators in the same country or region, using similar network technologies, and with comparable interception volumes.
When speaking with reference customers, ask about the deployment experience, the quality of vendor support, the platform’s reliability in production, the accuracy and completeness of intercepted data, and any challenges encountered during deployment or operation. Reference conversations can reveal issues that are not apparent from vendor documentation or demonstrations, and they provide a real-world perspective on the platform’s strengths and weaknesses.
If the vendor cannot provide references in comparable environments, this is a significant risk factor. A platform that has not been deployed and validated in an environment similar to yours carries deployment risk that must be carefully assessed and mitigated.
Conclusion
Evaluating a mediation platform requires going beyond surface-level feature comparisons and marketing materials. The seven questions outlined in this article — covering national interface support, network technology compatibility, scalability, security, deployment model, support commitments, and reference deployments — provide a framework for a thorough, substantive evaluation. By asking these questions and demanding detailed, verifiable answers, operators can make informed procurement decisions that result in a mediation platform that meets their compliance needs, supports their operational requirements, and adapts to the evolving demands of the lawful interception landscape.
Structuring the Evaluation Process
Beyond asking the right questions, operators should structure their evaluation process to enable fair and meaningful comparison between competing platforms. This means defining clear evaluation criteria and weightings before engaging with vendors, conducting hands-on demonstrations or proof-of-concept deployments where feasible, and involving all relevant stakeholders — including LI operations, network engineering, security, and legal — in the evaluation process. A structured evaluation reduces the risk of bias and ensures that the selected platform genuinely meets the operator’s needs across all dimensions.
Your choice of LI mediation platform will affect your operational capabilities for years to come. Ensure your LI mediation platform evaluation includes thorough testing with realistic traffic scenarios.
Related Articles
For further reading on related topics, explore these articles:
- What to Look for in a Lawful Interception Management System (LIMS)
- How a Mediation Function Works: The Bridge Between Your Network and Law Enforcement
- Temporary LI Box vs Permanent Infrastructure: When Does Each Make Sense?
External Resources
The following external resources provide additional context and official documentation:
