- `server` - a string containing the hostname or ip address of the server to test. Both IPv4 and IPv6 addresses are supported.
- `count` - an optional integer, default 5, specifying the number of ICMP Echo Requests to send to the server.
- `interval` - an optional number, default 1.0, in seconds specifying the delay between the sending of each echo request. To set this parameter, you must supply `count` as well.
- `timeout` - an optional number, default 2.0, in seconds specifying how long before an echo reply is considered to have timed-out. To set this parameter, you must supply `count` and `interval` as well.
- `class` - an optional string, default "any", specifying whether IPv4 or IPv6 should be used to send the ICMP packets. The string must be one of the following:
- `any` - uses the IP version which corresponds to the first address the `server` resolves to
- `IPv4` - use IPv4; if `server` cannot resolve to an IPv4 address, or if IPv4 traffic is not supported on the network, the ping will fail with an error.
- `IPv6` - use IPv6; if `server` cannot resolve to an IPv6 address, or if IPv6 traffic is not supported on the network, the ping will fail with an error.
- `fn` - the callback function which receives update messages for the ping process. See the Notes for details regarding the callback function.