Summary

The technical information (rationale) that the discussions around setting the resistibility requirements of telecommunication equipment installed in a telecommunication centre against lightning in Recommendation ITU-T K.20 were based on is shown in past contributions to ITU-T SG5 and various other documents. However, this technical information (rationale) has not yet been organized in the form of an informative document and is therefore not easy to find. Furthermore, users of Recommendation ITU-T K.20 who do not have an ITU account cannot access such information in the form of contributions or other documents.

Therefore, Supplement 24 to the ITU-T K-series Recommendations includes the technical information (rationale) on which the requirements for resistibility against lightning in ITU-T K.20 are based, which comes from past contributions and other documents discussed in ITU-T SG5.