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1. Riprogettazione del 
software 
In questo capitolo vengono evidenziate le principali esigenze sia storiche (legate all’espansione del 
Web) sia progettuali che hanno spinto e continuano tuttora a far pressione verso una 
riprogettazione del software per una maggiore accessibilità dei sistemi. In particolare verranno 
evidenziati gli aspetti propri dei legacy system. 
1.1 La crescita del Web 
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2. Architettura client server 
In questo capitolo sono evidenziate le principali caratteristiche del protocollo TCP/IP incaricato di 
trasferire le informazioni sul Web. Sarà illustrata l’architettura client-server, la quale discende 
storicamente da tale protocollo, nelle sue caratteristiche two e three-tier in relazione ai sistemi 
tradizionali e la loro riprogettazione in ambienti caratterizzati da una forte eterogeneità. 
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