IPv6 tunnel broker

Some years ago, I could connect to the IPv6 world over my IPv4 address by way of a free tunnel broker service. However, the service closed down in four years ago.

I have now used the tunnel broker of broker.aarnet.net.au in conjunction with gateway6 client which is basically a tunnel setup protocol (TSP) client. My new IPv6 address is :


which could be shortened to :


By the way, if we browse website by IPv6 addresses like :


It is necessary to use bracket to embrace the IP address:



how to find if a domain name is cached in a resolver

I have a task to test if a domain name is cached in a resolver. Of course, nslookup can not help and I have to turn to the more powerful dig.

#dig @ www.cnn.com +norecurse

If the domain www.cnn.com has already been cached, the results will show the corresponding A records. However, if it is not, the results give the NS records of the 13 rootname servers.



某天在一份文件中看見 WED,一時間想不起是那一個政府部門的簡寫。思前想後,民航處是 CAD、環保處是 EPD、消防處是 FSD 、社署是 SWD、渠務處是 DSD等,何來有個部門叫 WED。在百思不得其解之際,終於給我想通了, WED 原來 WEDNESDAY 的簡寫,亦即是星期三。看來以後不要把 ??D 聯想到是政府部門。


國金二期 = 黑夜之神



6-antenna access point

This is the first time I have ever seen a 6-antenna access point. The model is Motorola AP-7131 which can support 802.11a,b,g and n. When running on 802.11n 3x3 MIMO, the maximum speed can be up to 600 Mbps.

But don't be excited. This is an enterprise-grade access point. It is not a consumer product. Average home users might not have the chance to buy or use it.