HiNET的固定IPADSL - BBS

我是用HINET固定IP的ADSL
ppp.conf和rc.conf都已經設定好可以連的上網路
問題是電腦沒有在用的時候
網路好像會睡著＠＠
就是回不通...例如

-bash-2.05b$ ping 168.95.1.1
PING 168.95.1.1 (168.95.1.1): 56 data bytes
64 bytes from 168.95.1.1: icmp_seq=6 ttl=250 time=47.188 ms
64 bytes from 168.95.1.1: icmp_seq=7 ttl=250 time=49.051 ms
64 bytes from 168.95.1.1: icmp_seq=8 ttl=250 time=49.062 ms
^C
--- 168.95.1.1 ping statistics ---
10 packets transmitted, 3 packets received, 70% packet loss
round-trip min/avg/max/stddev = 77.228/85.688/94.059/6.872 ms

前面幾個封包不通後面才會通？？？
請問有沒有什麼解決方法

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