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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Dear All,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal> Somewhere I read that number of ROOT DNS servers is limited to 13 because of protocol limitation of DNS and UDP.<o:p></o:p></p><p class=MsoNormal style='text-autospace:none'>Exact writing was <span style='color:#77933C;mso-style-textfill-fill-color:#77933C;mso-style-textfill-fill-alpha:100.0%'>“</span><span style='font-family:"Courier New";color:#77933C;mso-style-textfill-fill-color:#77933C;mso-style-textfill-fill-alpha:100.0%'>A combination of limits in the DNS and certain protocols, namely the practical size of unfragmented User Datagram Protocol (UDP) packets, resulted in a limited number of root server addresses that can be accommodated in DNS name query responses. This limit has determined the number of name server installations at (currently) 13 clusters, serving the needs of the entire public Internet worldwide.”<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-family:"Courier New";color:#77933C;mso-style-textfill-fill-color:#77933C;mso-style-textfill-fill-alpha:100.0%'><o:p> </o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-family:"Courier New"'>As root DNS are running in anycast so number is not an issue at all. But I don’t understand where exactly is this limitation exists???<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-family:"Courier New"'><o:p> </o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-family:"Courier New"'>Please some elaborate on this.<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span style='color:#76923C'>Thanks and Regards,<o:p></o:p></span></p><p class=MsoNormal><span style='color:#76923C'>Gaurav Kansal<o:p></o:p></span></p><p class=MsoNormal><span style='color:#76923C'>9910118448<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>