The *host* option is used to make the interface look like they are running on the host itself. It allows the *Virtual Network Interface* greater network access than it can normally get.
If you use *host* then you'll get all ports listening on the host. This means you will need to check the services you runninf closely (especially if it's not yours, e.g. an official one provided by a software project) to make sure you don't inadvertently expose extra services on the network.