 Ung dung Client Server la ung dung co nhieu nguoi truy cap, thao tac voi co so du lieu chung dat tai server va nhieu may tram khac truy cap khai thac du lieu dung chung do; truong hop dac biet cung 1 may tram co the vua hieu chinh data chung lai tai server vua khai thac nhu mot nguoi dung thong tin client. VD nhu update tin tuc trong WEB++ va doc duyet lai thong tin nhu users thong thuong.
Ung dung Internet Web based la ung dung ma dat server tai Internet va truy cap tu cac may tram toi thong qua he thong server trung gian cua cac nha cung cap dich vu duong truyen ISP. (Co the dung lenh tracert http://lbvmt.net de xem di tu server nao den server nao.)
Duong di cua thong tin tu co so du lieu tai Hosting server toi May tram client nhu sau: - Doc len tu server hosting theo lenh cua phan mem
- Di qua he thong servers cua cac nha cung cap dich vu ISP
- Di qua he thong server tren mang noi bo
- Toi trinh duyet (Browser vi du Internet Explorer hay Firefox...) cua may khach dang truy cap Internet
De uu tien phuc vu luong lon Clients truy cap toi 01 server, khong lam cho nhieu clients cam thay viec phuc vu cung cap data cua Server cham, thong thuong he thong Web – based su dung cac bien phap “cache” luu tam thoi nhung data hay duoc client khai thac tai cac phan khac nhau cua he thong de clients doc nhanh hon, khong phai doi xu ly lai tai dau server. Cu the vi du thong tin Home page duoc cache dau do tai cac phan sau (xem so do):  - Cache chu dong tai phan mem, moi khi co yeu cau doc data base, phan mem tu luc lai data cache tam thoi; khong co moi truy cap data base doc data lai
- Cache tai hosting server do he dieu hanh phu trach dua tren thong tin nao hay bi yeu cau gui khoi server
- Cache tai servers tai cac nha cung cap ISP cung do nhu cau toi uu luu luong truy cap toi Website va yeu cau log truy cap ve an ninh
- Cache tai server cua mang LAN giup cho cac may trong mang noi bo cung doc toi 1 trang tai 1 site dung lai duoc cho nhau, nhanh hon
- Cache tai Internet Explorer de duyet di duyet lai cung 1 trang khong phai doc lai.
Vi vay, moi khi co so du lieu da thay doi, do cache chua duoc lam tuoi (Refresh ) nen ta van thay data la data cu. Ung dung application chi co the can thiep toi cache cua Software va caches tai Hosting server. Nhung caches khac nam ngoai kha nang quan ly cua Software. Thong thuong se do thiet dat va dung luong phuc vu cache, temporary directories, thoi han toi da can lam tuoi lai cache… dat tai server ISP, server cua mang LAN hoac chinh trinh duyet Internet Explorer. Article source http://w4rum.com/182.t
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