How does DDoS attacks affect VoIP phone systems?

In computing, a denial-of-service (DoS) or distributed denial-of-service (DDoS) attack is an attempt to make a machine or network resource unavailable to its intended users. Although the means to carry out, motives for, and targets of a DoS attack may vary, it generally consists of efforts to temporarily or indefinitely interrupt or suspend services of a host connected to the Internet. As clarification, DDoS (Distributed Denial of Service) attacks are sent by two or more persons, or bots. (See botnet) DoS (Denial of Service) attacks are sent by one person or system.

The standard definition of a DDoS attack is listed above from Wikipedia, and unfortunately this is just the world we live in. DDoS attacks happen all the time, some for no reason at all. PBX systems are no different than anything else on the internet. Today we experienced an issue with one of our Allworx PBX systems. The official event in the log is:

04/07/2014 06:40:42am tSysTask: TASK Sys: Memory stats: 134180 bytes available (max block 15692)

Now this log doesn’t look like much but essentially this is the after effects of a DDoS attack causing memory leaks on the Allworx PBX system. All PBX systems in the industry are no different in that they are all open at some point to DDoS attacks. For a breakdown of how Telecom Solutions protects the Allworx PBX see our article on Important Security Best Practices.