ional criteria. SON concepts (as discussed in Chapter 2) include measures that address such automatic evolution decisions. A Specific Example One of the events that tends to affect functioning of networks is the problem of "flash crowds." Wikipedia (http://en.wikipedia.org/wiki/Flash_mob) defines "flash mob," which is the equivalent of a flash crowd, in the physical world as follows: A flash mob (or flashmob) is a group of people who assemble suddenly in a public place, perform an unusual and seemingly pointless act for a brieftime, and then quickly disperse, often for the purposes of entertainment, satire, and artistic expression. Flash mobs are organized via telecommunications, social media, or viral emails. In a networked world, a similar phenomenon can occur that may be related to the flash mob scenario: communication networks are overloaded due to many people physically arriving at a location as part of an unplanned event (from service provider perspective) or it may be related to conditions occurring online in other parts of interconnected networks that may be sending more traffic in a burst to the network under scrutiny, more commonly called a Slashdot effect, which Wikipedia defined as (http://en.wikipedia.org/wiki/Slashdot_effect): The Slashdot effect, also known as slashdotting, occurs when a popular website links to a smaller site, causing a massive increase in traffic. This overloads the smaller site, causing it to slow down or even temporarily become unavailable the name is somewhat dated as flash crowds from Slashdot were reported to be diminishing as of 2005 due to competition from similar sites. Typically, less robust sites are unable to cope with the huge increase in traffic and become unavailable-common causes are lack of sufficient data bandwidth, servers that fail to cope with the high number of requests, and traffic quotas. A flash crowd is a more generic term without using any specific name that describes a network phenomenon where a network or host suddenly receives a lot of traffic. This i