Dear Chuansong, By the way, I tried to evaluate the connectivity to IHEP via CAS. The PING from KEK to www.cas.ac.cn showed ----www.cas.ac.cn PING Statistics---- 101 packets transmitted, 60 packets received, 40% packet loss round-trip (ms) min/avg/max = 553/595/691 ms , and my Web access to www.cas.ac.cn took a very very long time. At the same time, the PING to www.ihep.ac.cn showed ----www.ihep.ac.cn PING Statistics---- 101 packets transmitted, 101 packets received, 0% packet loss round-trip (ms) min/avg/max = 121/265/976 ms The traceroute from KEK to www.cas.ac.cn showed as follows: keknwf.kek.jp[61]% traceroute www.cas.ac.cn traceroute to www.cas.ac.cn (159.226.2.10), 30 hops max, 40 byte packets 1 130.87.56.203 (130.87.56.203) 11 ms 2 ms 2 ms 2 kekcis-lan (130.87.1.129) 9 ms 2 ms 3 ms 3 kekcis7-fddi (130.87.2.7) 9 ms 3 ms 3 ms 4 202.13.223.198 (202.13.223.198) 10 ms 8 ms 7 ms 5 nacsis-gate5.sinet.ad.jp (150.99.99.5) 11 ms 14 ms 8 ms 6 abilene-A1-0-0-1.sinet.ad.jp (150.99.200.194) 123 ms 122 ms 122 ms 7 abilene.gw.sinet.ad.jp (150.99.200.206) 123 ms 123 ms 125 ms 8 scrm-losa.abilene.ucaid.edu (198.32.8.17) 131 ms 131 ms 131 ms 9 dnvr-scrm.abilene.ucaid.edu (198.32.8.2) 155 ms 156 ms 153 ms 10 kscy-dnvr.abilene.ucaid.edu (198.32.8.14) 163 ms 174 ms 165 ms 11 ipls-kscy.abilene.ucaid.edu (198.32.8.6) 172 ms 173 ms 172 ms 12 st-abilene.startap.net (206.220.240.205) 161 ms 164 ms 160 ms 13 202.112.61.5 (202.112.61.5) 680 ms 669 ms 753 ms 14 202.112.61.222 (202.112.61.222) 1201 ms 1100 ms 1099 ms 15 202.112.36.242 (202.112.36.242) 1075 ms * * 16 * * * 17 * * * 18 * st-abilene.startap.net (206.220.240.205) 848 ms * 19 * abilene-st.startap.net (206.220.240.206) 777 ms 764 ms 20 * st-abilene.startap.net (206.220.240.205) 764 ms * 21 abilene-st.startap.net (206.220.240.206) 920 ms 922 ms 916 ms 22 * * * 23 * * * 24 * * * 25 * * 159.226.2.10 (159.226.2.10) 295 ms keknwf.kek.jp[62]% And the second try showed as follows: keknwf.kek.jp[62]% traceroute www.cas.ac.cn traceroute to www.cas.ac.cn (159.226.2.10), 30 hops max, 40 byte packets 1 130.87.56.203 (130.87.56.203) 10 ms 3 ms 2 ms 2 kekcis-lan (130.87.1.129) 9 ms 2 ms 2 ms 3 kekcis7-fddi (130.87.2.7) 10 ms 3 ms 2 ms 4 202.13.223.198 (202.13.223.198) 10 ms 8 ms 8 ms 5 nacsis-gate5.sinet.ad.jp (150.99.99.5) 11 ms 8 ms 8 ms 6 abilene-A1-0-0-1.sinet.ad.jp (150.99.200.194) 124 ms 123 ms 123 ms 7 abilene.gw.sinet.ad.jp (150.99.200.206) 124 ms 124 ms 124 ms 8 scrm-losa.abilene.ucaid.edu (198.32.8.17) 131 ms 130 ms 130 ms 9 dnvr-scrm.abilene.ucaid.edu (198.32.8.2) 153 ms 154 ms 153 ms 10 kscy-dnvr.abilene.ucaid.edu (198.32.8.14) 164 ms 164 ms 164 ms 11 ipls-kscy.abilene.ucaid.edu (198.32.8.6) 172 ms 172 ms 172 ms 12 st-abilene.startap.net (206.220.240.205) 161 ms 230 ms 160 ms 13 202.112.61.5 (202.112.61.5) 259 ms 267 ms 250 ms 14 * 202.112.61.222 (202.112.61.222) 835 ms 818 ms 15 * 202.112.36.242 (202.112.36.242) 825 ms * 16 202.112.1.62 (202.112.1.62) 856 ms * * 17 * beijing-sgw-lan.cernet.net (202.112.1.202) 845 ms * 18 * * * 19 * * * 20 * * * 21 * * * 22 159.226.254.145 (159.226.254.145) 581 ms * 607 ms 23 159.226.254.142 (159.226.254.142) 618 ms 638 ms 648 ms 24 159.226.254.70 (159.226.254.70) 587 ms 610 ms 605 ms 25 * * 159.226.2.10 (159.226.2.10) 595 ms keknwf.kek.jp[63]% I expect that this be not a fundamental problem in the CAS's external connectivity. Best regards, Yukio