This article I wrote in the purpose to understanding how some of unofficial chat client of Yahoo Messenger protecting their self from being booted. As long as I knew, Yazak, Yahaven and also YmLIte chat client, used Chat Shield through some idea relating with Alias ID.
They used Alias ID to make it dis-active or inactive when the boot attack detected by the software of chat client. With this inactive ID, the boot unable to make an attack cause actually, the ID was "dead". How many bots that will attack the "dead" ID they will face nothing or useless. That the Idea how the chat client must used Alias ID before the applied or activate Chat Shield on Chat Room of Yahoo Messenger.