Futurewei Technologies Ltd. Cisco Systems, Inc. Bell Canada Huawei Technologies Cisco Systems, Inc. Cisco Systems, Inc. Cisco Systems, Inc. A clear application of the SRv6 Network Programming model consists in steering, in a stateless manner, packets through a Service Function Chain (SFC). Each Service Function (SF) is identified by a segment. Each SF can enrich its operation thanks to metadata present in the SRH. This document describes a practical use-case where the SF is a firewall and the metadata helps to drastically decrease the number of rules that need to be maintained by the operation team.