1. A system comprising: a name resolution server including a physical processor configured with specific computer-executable instructions to: receive, from a first computing device, a request to resolve an identifier of a set of content on a content delivery system; determine a first combination of network addresses for the set of content based at least in part on an identifier of the first computing device, wherein the first combination of network addresses is selected from a set of network addresses at which the set of content is made available by the content delivery system; transmit the first combination of network addresses to the first computing device; receive a request to resolve the identifier of the set of content from a second computing device; determine a second combination of network addresses for the set of content based at least in part on an identifier of the second computing device, wherein the second combination of network addresses is different from the first combination of network addresses; transmit the second combination of network addresses to the second computing device; a network attack source identification server including a physical processor configured with specific computer-executable instructions to: detect a network attack on the content delivery system, the network attack directed to a plurality of network addresses; determine that the plurality of network addresses to which the network attack is directed is included in the first combination of network addresses transmitted to the first computing device; derive the identifier of the first computing device from at least the first combination of network addresses transmitted to the first computing device; and identify the first computing device as associated with the network attack.