the trickle-down effect: web caching and server request

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ABSTRACT Keywords 1. INTRODUCTION

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request stream

Internethosting network

server cluster

requestdistributorsurrogate

caches

CDN servers

proxy caches

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100

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1998 IBM TraceMiss stream PDF

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4 8 12 160

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Number of back−end servers

Load

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100

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No Front End Cache32MB Front End Cache64MB Front End Cache128MB Front End Cache

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5. CONCLUSIONSÎ4�~ V�+½HG�½\U��+�l�~DSÂ�E£a�~G�£+ÃqU�RMG-�l�lÈQ�*½Q£a VDZFQ�+G-¼\DZÈT£»�Uy¼��lUs�aÀqU���aUSÒ�È~U��z£O£l�gG�ã*Ê4�0GyR�IVUSG-J�È~�=G��z£l�gGyRoG��O½Q�aDS¿�R�ÊyG-Êg�~Uy�=G�FHJo�AD-FQÌ£aUyF�£BP!U�IK VÀqUs�lR0Á�U�£iÂ4D-�aÃ��!Ä«�AP�Á��gÆt¼\UyÊ�DZ�*U� VFQÊ��aUSG-�l VFQÏZIÇRÅÈ~¼~ KÒqÌÈ~ Ç£aD-È~�MG-FHJÓU���UyÊ�£a VÀqUZN Î�D,¼\Up�lÈQ�aUZѽ\Us�lаUyÊ�£5ÊSG-Êg�~ VFQÏ�Â4DZÈQIKJG-¼Q�lD-�a¼ `Z[°[ �z£gG�£a VÊ4DZ¼�×zU�Ê�£O�aUSÒ�È~Uy�z£a�yÑ�IVUSGSÀ� VF~Ï�D��a VÏZ VFÉ�l Ç£aUy�µ£aD+�HG�FQÌJQIVU�JTRTFHG��* VÊËÊyDZF�£aUyF�£�G-FHJ�½T�aDZ½~G-ÏqG?£aU�D-¼T׺UyÊ�£�È~½�J~G?£aUy�E£aDo£a�QUÊSG�Ês�Q KFQÏÚF~U�£iÂ4D��aÃT�yN�âAÈQ£�UyÀqU�F¾ V�*½\U��lаU�Ê�£ÉÊyG-Êg�~Uy�%ÊSG-F}G�¼~�lD��a¼£a�~UB�0GS×zD��a Ç£ºRoD�Ð\�aUSÒ�È~Uy�z£a�O£aD!£a�QUB�*DZ�z£@½\DZ½QÈ~IKG��tDZ¼�×zUyÊs£a�yÑ��l�~ ÇЯ£lÌ VF~Ï�JQDSÂF~�z£l�aUyG-��£l�gG?ã*Ê�IVDZGZJQ�4£aDSÂ4G��gJ*£a�~U+�~USGSÀ�Ro£gG- VI�D-еØ\ K½TЯÌIV VÃqU%»¾Uy¼Ú�aUSÒ�È~Uy�z£!JQ V�z£l�a V¼~ÈT£a KD-F~�yN�Î4�Q V��ôi£l�a VÊgÃTIVU�ÌiJTD?ÂFpU���U�Ê�£aõ V�*½HG�Ê�£a�4£a�~U�JTUy�l VÏZF�D�Ð=JQDSÂF~�z£l�aUyG-�óÊyDZ�*½\D-F~UyF�£a�yN6 ÈQ���aUy�lÈ~IÇ£a�= VIKIVÈQ�z£l�gG�£aU4£a�~UA K�*½\D��l£gG-FQÊyU4D-Ð~ÊyDZFQ�l KJQU��a VF~ÏE£a�~U4 V�o̽HG�Ê�£tD-ЭÊSG-Êg�~ VFQÏËDZF0D-£a�QU��AÊ�DZ�*½\DZFQUyF�£a�=D-Ð�G-F*UyF~JTÌ_£aD-Ì«UyF~J�ÊyD-FQÌ£aUyF�£ËJTUyIV VÀqU��lRpG?�aÊs�Q V£aU�Ê�£aÈQ�aUZN!Î4�~ V�!½~G-½\U��ËUs¿Q½QIVD-�aUy�EÃqU�RÚ V�*½~IV ÇÌÊSG?£a KD-F~�oD�ÐE£a�QU*£l�a KÊgÃ�IVU�ÌiJQDSÂF}U���UyÊ�£�аD-�É�aUSÒ�È~Uy�z£oJQ V�z£l�a V¼~ÈQ£a VD-FG-IÇ£aU��aF~G�£a VÀqUy�� KFp¼~G-ÊgÃ�Ì«UyF~J��lU��aÀqU��!ÊyIVÈ~�z£aU��a�yN�Î4�QU%£l�a VÊgÃ�IKUs̺JTDSÂFU���UyÊs£E�lÈQ½~½T�aUy�l�lUy�£a�~U˽Q�a V�0G?�lRM�lD-ÈQ�aÊyU�D�Ð=IKDZGZJÚ V�ɼ~G-IKG-FQÊyUy� VF»�U�¼��lUs�aÀqU���аG��a�*�yÑ\�aUSJTÈ~Êy VFQÏ0£a�QU�½\D�£aUyF�£a KG-IO¼\UyFQU Û £EЯ�aDZ�#�lD-̽~�Q V�z£a KÊyG�£aUSJÚIVDqG-Jp¼~G-IKG-FQÊy VF~Ï0�z£l�gG�£aU�ÏZ VUy��ЯD-�!�z£gG?£a VÊ�ÊyD-F�£aUyF�£SNÍi£G-IV�lD�G-¼Q�lD-�a¼~�t�ÉÈQÊs�oD�Ð�£a�~UIVD�ÊSG-IV Ç£ºR0 VF*£a�~UB�aUSÒ�È~U��z£A�z£l�aUSG���Ñq�aU�ÌJQÈQÊy VF~ÏÅ£a�~Uɼ\U�F~U Û £!Я�aD-�wJQDSÂF~�z£l�aUSG���ÊyD-F�£aU�F�£!ÊSG-Êg�~Uy�0ÄcUZN ÏTNKÑ�lU��aÀqUs�B�*Uy�*D-�lR~ÆsN�ͺF0£a�~U+IK V�* Ç£SÑTÈ~½Q�z£l�aUSG-��ÊSG-Êg�~Uy�4ÂAUSG-ÃZUyFÅ£a�QUJQ Ç��U��aU�F~ÊyUy�0¼\U�£iÂ4UyU�FÓ�aUSÒ�È~U��z£ÅJQ V�z£l�a V¼~ÈQ£a VD-FÕ�z£l�gG�£aU�ÏZ VUy�MJQDSÂFQÌ�z£l�aUSG���NOÎ4�~UtÀZG?�a VDZÈ~�O�z£l�gG?£aUyÏZ VUy�@G?�aU4�*D-£a VÀ-G�£aUSJËIKG��aÏ-UyIÇR�¼�R!£a�QUIVD�ÊSG-IV Ç£ºR¾G-F~J�IVDZGZJ;�lÃZU�  VF~�QU��aUyF�£Ë VF;£a�QU¾ôº�QUSGZJTõ5D�ÐØ\ K½TЯ̫IV VÃqU�aUSÒ�È~U��z£0JQ V�z£l�a V¼~ÈT£a KD-F~�yÑAG-F~JÖ¼\Uy�~GSÀqUM�l V�* VIKG��aIÇR}DZF}£a�~UM�~USGSÀ�R£gG- VIcN@í=ÀqUyF*�lDQÑ�£a�QUE½~G��l£a KG-IQ�aUSJQÈQÊ�£a VDZF* VF0IKD�ÊyG-IV Ç£ºR*Я�aD-���*D�JTU��lÌG�£aU�IVRoU���UyÊ�£a VÀqUBаD��lÂBG?�gJÅÊSG�Ês�QUy�A�0G�ÃqUy�@ÊyDZF�£aUyF�£lÌiGyÂBG?�aU�aUyÒ�ÈQUy�z£JQ V�z£l�a V¼~ÈT£a VDZFáÄcUZN ÏQNVÑ@Þ�CEßÕ�~G-�l�~ VFQÏ�ÆËUyÀqUyF��*D��aU0 K�*½\D��l£gG-F�£% VFJQDSÂFQ�z£l�aUSG-� �lUs�aÀqU��OÊyIVÈQ�z£aU��a��£aD+¼\UyF~U Û £µÐ¯�aD-�Ô£a�QUAIVD�ÊSG-IV Ç£ºR�£a�~G�£�aUy�0G� KFQ��:~Ê�DZF�£aUyF�£lÌ«¼~IV VFHJM½\D-IV KÊ� KU��E�lÈQÊs�ÚG���lU��aÀqU��+IVDqG-J�¼HG-IKG�F~Ê�Ì VF~ÏÖÄ@C�D#E~ÆÉ�lUyÀqU��aU�IVR}Ê�DZ�*½Q�aD-�* V�lUM�lU��aÀZU��*ÊSG�Ês�QU5U���UyÊs£a KÀZUyF~Uy�l�yÑUyÀqU�FM ǣa���l�0G-IVI�Я�aD-F�£lÌ«UyF~JMÊSG�Ês�QUy�yNÎ4�~ V�0�z£aÈHJ�R,аD�ÊyÈQ�lUy�0DZFÓ�z£gG�£a VÊÚÊyDZF�£aUyF�£SNÓP�RTFHG��* KÊÅ»�Uy¼}�aU�ÌÒ�È~Uy�z£a�=G?�aU4£l�gGZJT V£a VD-FHG-IVIÇR�F~D-£=ÊyG-Êg�~USG�¼~IVUZN=à�DSÂAUyÀqU��SÑ� ǣa�É£aUyÊg�QÌF~ KÒ�È~U��t�lÈQÊs�*G��4J�RQF~G-�* VÊ4ÊSG�Ês�Q VF~ÏðøÇìSê?ù�G�FHJÉЯ�gG�ÏZ�*UyF�£@ÊSG�Ês�Q KFQÏø n�ùÕø îSù� Ç£ V�½\DZ�l�l V¼~IVUË£aDÉÊyG-Êg�~U˽HG?�l£D-ÐO£a�QUE�aUy�lÈQIV£+D�Ð=JTRTFHG��* VÊ�aUSÒ�È~U��z£a��Ä°Â�~ VÊg�ç�0GyRåG-½Q½~IÇRá£aDÖ�0G-F�RåJQ Ç��U��aU�F�£5�aUSÒ�È~Uy�z£a�gÆsÑÏqG� VF~ VF~Ï��lDZ�*U+¼\UyF~U Û £AÐÙ�aDZ�ðIVD�ÊSG�IV V£iR�NtÎ4�~Uy�lUEU���UyÊ�£a�4��È~�z£4G-IV�lD¼\UËÊyD-F~�l KJQU��aUyJ5Â�~UyFÚ�z£aÈ~JTRT VF~Ï�£a�QU� K�*½~G-Ê�£a�D�Ð= KFQÊ��aUSG��lUSJÚJTR�ÌFHG��* VÊ!ÊyDZF�£aUyF�£ VF5»¾Uy¼M�aUSÒ�ÈQUy�z£a�yN

6. ACKNOWLEDGEMENTS»�U+Â4D-È~IKJÅIV VÃqU�£aD�£a�HG�F~Ã*íO�a VÊs�MÁ!G��TÈQ��D�еͺâB¡)CEU��lUSG��aÊg�ÅЯD-�½Q�aD?À� KJQ VF~ÏMÈ~�Ë£a�~UMìSëZë-é�ÍzâB¡�ÂAUy¼¾�lU��aÀZU���£l�gG-ÊyUy��ÈQ�lUSJ; VF;£a�QUß � CEPý�z£aÈHJ�R�NË»�U�Â4D-È~IKJ¾G�IK�lDMIV KÃZUÉ£aDÅ£a�~G-FQà � IV V�z£aU��%ß�Us K�zÌâADSÂ4U�FoG-F~J � FHJ��aU�Â}æQ�gG�F~Ã�Ìiß�D-�aD-F%ЯD-�O£a�QUy Ç�O�~UyIV½% VF�D-¼Q£gG- VFQ KFQÏ£a�~UËê-èZè�ì�ÍzâB¡ï�lU��aÀqUs�IKD-ÏZ�yN

7. REFERENCESè é�ê\ëTìzítîªïÂð#ñóòtô�õZöÂ÷0ø!ö�î�ðö�îaù/ö�î�ú"ï$îªì�û�ò#üÂöWýWñ þªÿ���ö�������ïû�

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