Client-server architecture server. always-0 n host谷歌金永 在线主 permanent IP address server farms for scaling谷歌金山为扩大服务器群 clients communicate with server client/server may be intermittent!(间歇 地 connected may have dynamic IP addresses do not communicate directly with each other uct by Weifeng Sun chapter 2-application layer 7/73Introduct by Weifeng Sun chapter2- application layer 7/73 Client-server architecture server: – always-on host(谷歌金山:永远 在线主机) – permanent IP address – server farms for scaling(谷歌金山:为扩大服务器群) clients: – communicate with server – may be intermittently(间歇 地)connected – may have dynamic IP addresses – do not communicate directly with each other client/server