1. ETSI ISG NFV: ETSI GS NFV 002 V1.2.1: Architectural Framework (2014). https://www.etsi.org/deliver/etsi_gs/NFV/001_099/002/01.02.01_60/gs_NFV002v010201p.pdf
2. Azadiabad, S., Khendek, F., Toeroe, M.: Availability and service disruption of network services: from high-level requirements to low-level configuration constraints. Comput. Stand. Interfaces 80, 103565 (2022)
3. ETSI ISG NFV: ETSI GS NFV-REL 001 V1.1.1: Resiliency Requirements (2015). Available: http://www.etsi.org/deliver/etsi_gs/NFV-REL/001_099/001/01.01.01_60/gs_NFV-REL001v010101p.pdf
4. Huawei Technologies: Challenges of 5G Ultra Reliability. Huawei Technologies (2018). http://cqr.committees.comsoc.org/files/2018/07/05-Dehan_Li-Challenges-of-5G-Ultra-ReliabilityETR-052618.pdf. Accessed July 2022
5. Von Alven, W.H.: Reliability Engineering. Prentice-Hall, Englewood Cliffs (1964)