Some people replied me about my questions. thanks for reply. However, what I want to know ultimately is something like technical proof or standard or experimentation information they can logically support SLA values in provider's IP network. For example, regarding packet loss, I found information it is based on voip service tolerance (al least below 1% packet loss). but some provider announce they can guarantee 0.3% packet loss. Where does 0.3% come from ? Can anyone give me an answer about this question ? In fact I am going to make some guideline of network quality of my network. Best regards, Chiyoung ------- Original Message ------- Sender : 정치영<lionair@samsung.com> 과장/인프라기술1팀/삼성네트웍스 Date : 2009-04-08 13:05 (GMT+09:00) Title : SLA packet loss base Hi all, I wonder where we can find the base of packet loss rate of Global famous provider. For example, the packet loss value of Sprint and NTT-Verio is same 0.3 % at their SLA. Best regards Chiyoung ============================================= Chi-Young Joung SAMSUNG NETWORKS Inc. Email: lionair@samsung.com Tel +82 70 7015 0623, Mobile +82 17 520 9193 Fax +82 70 7016 0031 =============================================