What is the variable valertpubkey in net.cpp for? vAlertPubKey = ParseHex("04fc9702847840aaf195de8442ebecedf5b095cdbb9bc716bda9110971b28a49e0ead8564ff0db22209e0374782c093bb899692d524e9d6a6956e7c5ecbcd68284");


The vAlertPubKey variable can be seen in the initialisations for main and test network, but not for regtest. Can someone explain what it exactly means and how will it affect me if I want to simulate a network of 1000 or more nodes on a private network in regtest mode ?
One of the people who holds the private key corresponding to that public key (Satoshi, theymos, Gavin, and unspecified others) has the ability to send a message out to everyone on the network. This has been used in the past to tell people about security vulnerabilities in the client.


  Can someone explain what it exactly means and how will it affect me if I want to simulate a network of 1000 or more nodes on a private network in regtest mode ?


Assuming you're not testing the alert system, it won't affect you.