EVE features a "security index system". Every solar system in the EVE universe has a public security status which ranges from 0.0 to 1.0. Systems with a rating of 0.0 are completely lawless; 0.1 to 0.4 have absolutely no protection by CONCORD, the NPC law enforcement, but are covered by sentry guns at stargates and stations; 0.5 to 0.8 systems have moderate protection, with 0.9 and 1.0 systems being considered extremely secure. Any time a player commits an act of aggression in a system with a security rating at or above 0.5, CONCORD ships and/or stationary weapons platforms will attack and destroy the aggressor (something known affectionately by players in EVE as "CONCORDOKEN").

At the time of its release, EVE Online was known for its highly detailed graphics (at the very least, for an MMORPG). EVE is played entirely on one large server cluster named Tranquility, however a Chinese shard is expected to launch soon . All the players (not testers) are on the same server cluster and in the same game-world. Whenever the server is down for maintenance, server load is redistributed according to how much traffic each system received during the previous play period. Therefore, unpredictably large numbers of players in one system tend to cause lag, and large-scale events (such as fleet battles) can be made impossible. On Sunday, January 15th, 2006, EVE Online achieved a new record for the maximum number of simultaneous avatars online with 23,123 concurrent accounts logged on to the same server. In recent months, EVE Online has been setting such records almost every week.

The servers have a scheduled daily downtime between 11:00 and 12:00 GMT. (So you can't play during that hour.)

Growth and Instability
EVE Online is currently growing at a rapid rate, reaching a new record for the maximum number of simultaneous accounts logged on with 23,037 online on January 15th, and has an average of about 14,000 players online at any one time. This rapid growth has out-run CCP's gradual hardware introduction and software optimization plan, and the server cluster is currently straining from it. In the days after the release of the Red Moon Rising content patch, which included many underlying changes, the single server cluster EVE runs from, 'Tranquility', saw extreme lag and frequent system-wide crashes because of this low margin of error. During these events CCP's CEO, Hilmar Pétursson, wrote a developer blog explaining to the userbase the problems facing EVE, and what CCP were doing to resolve them [1]. Underlying this change is the switch from 32-bit architecture to 64-bit architecture, necessitating a cluster overhaul in the near future. When this is completed, it is hoped EVE will offer increased performance to a wider audience.