Level 3 Outage
Level 3 Communications is a huge network provider. They sell all kinds of networking services, including IP transit, VOIP, and cloud services. Their primary ASN is AS3356. A network as large as Level 3's is going to suffer outages from time to time. There are a number of tools you can use to see if Level 3 is currently having and outage, and if your area or service is likely to be affected by this outage.
All networks have outages. I can guarantee that right now there are fiber paths which are down. It happens. There is never a time when all Internet connections work. The thing to remember is that the end user almost never notices these outages because a good network will have multiple different paths to reach a certain point.
Level 3 is good in that sense. Because they are so large, their network outages are likely to be unnoticed. A single fiber cut is not likely to affect most Level 3 customers. At the same time, when there is a larger problem, it will have a larger effect. When level 3 has a large outage it is much more noticeable than when smaller networks have outages.
About a week ago Level 3 had an VOIP outage which resulted in customers all over the country not being able to make or receive calls. This outage happened to affect calls that were not local. The root cause of the issue was a provisioning error. Someone mistyped a configuration that was then sent to multiple switches across the network.
It took Level 3 about an hour and a half to find and resolve the problem. That response time is not terrible, but this outage really should have been avoided. configuration changes such as this should be tested in a test environment within Level 3. The company is large enough that they should be able to afford proper testing before setting a system-wide configuration change.
Just about any experienced network engineer can tell you that things like this happen sometimes. Messing up a config is not super rare. The issue here is the lack of testing.
Check if Level 3 is having an outage
The first place to check if Level 3 is having an outage is their looking glass. A looking glass allows you to run certain commands on Level 3's routers. These include ping and traceroute, two very common network testing tools. Using their looking glass you can also check certain BGP settings.
The looking glass allows you to run a very limited amount of commands. The same commands a Level 3 technician would run to diagnose problems that you may be seeing.
Other than the looking glass, there are a few third party website which track outages. These are not going to be as accurate as the Level 3 tools, but they can help you see if there is an indication of a larger outage. These sites include http://downdetector.com/ and http://www.internethealthreport.com/.
One final place to see the status of Level 3's network is on their Twitter page.
Using these tools you should be able to get a good idea and see if Level 3 is having an outage. If you are having network issues, it is extremely helpful to know if the issue is on your side of things or on the side of you uplink provider.