This question leads to an iceberg answer, in that there’s a lot to say. Here’s the tip, so to speak:
> I can ping the tower but tracert does not work (or takes an inordinately long time).
The short answer is that you are most likely not pinging the tower, but something more local. The DNS servers are not likely to be local either, so DNS name resolution isn’t likely to work either when you are having connectivity issues.
The analogy here is that to reach an endpoint (specified by IP address, possibly after the additional step of DNS name resolution from a textual name to an IP address that is an independent network operation that itself requires a healthy network connection), you have to traverse a network of roads. You can think of each intersection on this network of roads as having its own IP address. To get almost anywhere, the first few intersections are going to be the same, they take you from your home, out of your neighborhood, and onto a major road. Once you’re on this road, chances are you are going to get where you are going, unless there is a problem toward the other end of the journey, when you are getting back onto local roads in the destination neighborhood. Or, if there’s no one home at the address on the other end (the site or server is out but you can get to everything else).
There is a span of road that is sometimes out in your case, most likely the over-the-air link. If this happens, you can reach intersections or even end addresses that are local and do not require traversing the span where there’s an outage, but can’t get further.
Take a tracert when things are working, and let the IP addresses be resolved back into textual names (don’t turn of DNS resolution when tracert for a working connection). These names may give you clues. Keep the list of names and IP addresses to some well-known site handy for comparison when things are out.
You will likely find that when you run a tracert that stops at some point, you can ping the addresses that it could reach, you just can’t ping ones that are further away on the network. The first place you can reach when things are working but cannot when they are out is the far end of the link that is giving you problems. If you want, you can post details here and we can comment further.
Hope this helps!