The ICMP (Internet Control Message Protocol) ping is the simplest and most common target type. It sends a well-defined message to an IP address and checks the response.
The chief drawback to ICMP pings is that many web servers, modern operating systems and firewalls block ICMP pings by default to avoid such problems as "denial of service" attacks. However, many web sites still allow you to ping them.
This type of ping allows you to test if the server is accessible over the internet (using whatever Wi-Fi or cellular connection you may have). It does not guarantee that particular services such as HTTP (web servers) are available.
In the full version, this type of ping may use the free program PVProxy if the target is behind a firewall.
TCP (Transmission Control Protocol) is the most common method by which data is exchanged over the internet. Every TCP connection operates over a "port number", which is like a telephone extension number in an office building-- it specifies the particular service you wish to connect to. Web servers, for example, run TCP over port 80.
This type of ping attempts to open the TCP port you specify; if it succeeds, it immediately closes the port. This sort of action, commonly called a "probe", will not negatively affect any stable TCP-based service. It allows you to directly check if a particular service is available.
In the full version, this type of ping may use the free PVProxy program if the target is behind a firewall.
A proxy extension is a user-provided add-on to the PVProxy program. Extensions allow network administrators to perform advanced tests such as querying databases and monitoring file systems.
This type of ping requires a proxy. Each extension is given a unique name which you must enter as part of the target specification for a proxy extension target.
Extensions are programs using Microsoft's .Net language family. In addition, a free extension allows you run any Windows "shell' scripts you specify.
Another free program, PingView, can be used to view dozens of computers behind a firewall. It also requires a proxy.
ProbeView (running on your iPhone) routes a request through PVProxy to a copy of PingView running on the same or another machine. When you perform a refresh, the status of the target reflects the status of the entire remote network. Tapping on the target reveals a list of the remote targets and their individual statuses.
See the "Subordinate Targets" page for more information about PingView server targets.
Also, you can use PingView as a "repository" to store the results of other PingViews running anywhere in the world. Each set of PingView targets is called a "collectïon", and each collection is associated with a globally unique identifer. So if you're using multiple PingViews and they send their information to a "central" PingView, you can use the "Collection Guid" field in a PingView target to specify the collection you wish to associated with that particular ProbeView target. For more information, read the PingView help pages.
To add a target, click the "plus" button on the Targets page. To edit a target, use the "disclosure" button (blue right-pointing arrow) on the target's entry in the Targets page. To delete a target, swipe across the right-hand edge of the target's entry from right to left and a Delete button will appear.
You can also click the 'Edit' button to delete targets. You can also reorder (move) the targets when the page is in 'edit'mode. To leave 'edit' mode, click the 'Cancel' button.