Re: what?
[Citation needed], but I'm guessing that's a reference to section 48 of the Telecommunications (Interception Capability and Security) Act 2013:
http://www.legislation.govt.nz/act/public/2013/0091/latest/DLM5178093.html
This requires network operators to advise the GCSB when they make changes within "areas of specified security interest" as defined in section 47. That section lists things like interception capability, storage of customer or network admin credentials, and parts of the network that aggregate large volumes of customer data (in flight or at rest). I'm neither a lawyer nor a network engineer, so hopefully someone better qualified can explain what this all means in practical terms.