Machine Learning (ML) techniques have shown strong potential for network
traffic analysis; however, their effectiveness depends on access to
representative, up-to-date datasets, which is limited in cybersecurity due to
privacy and data-sharing restrictions. To address this challenge, Federated
Learning (FL) has recently emerged as a novel paradigm that enables
collaborative training of ML models across multiple clients while ensuring that
sensitive data remains local. Nevertheless, Federated Averaging (FedAvg), the
canonical FL algorithm, has proven poor convergence in heterogeneous
environments where data distributions are non-independent and identically
distributed (i.i.d.) and client datasets are unbalanced, conditions frequently
observed in cybersecurity contexts. To overcome these challenges, several
alternative FL strategies have been developed, yet their applicability to
network intrusion detection remains insufficiently explored. This study
systematically reviews and evaluates a range of FL methods in the context of
intrusion detection for DDoS attacks. Using a dataset of network attacks within
a Kubernetes-based testbed, we assess convergence efficiency, computational
overhead, bandwidth consumption, and model accuracy. To the best of our
knowledge, this is the first comparative analysis of FL algorithms for
intrusion detection under realistic non-i.i.d. and unbalanced settings,
providing new insights for the design of robust, privacypreserving network
security solutions.