It depends on the delivery method. Peer-to-peer eCDNs run in the browser and need no installs or network changes. Caching eCDNs place an appliance or server at each site. Multicast eCDNs use the network you already have, but multicast has to be enabled on routers, switches, and wireless controllers. Most large deployments combine methods, so the hardware question is answered site by site rather than once.