2005/03/31

ACER Travelmate 280


I have been using Acer Travelmate 280 notebook PC for two years. This notebook comes with a P4 1.8GHz CPU and 256 MB DDR by default. Pretty stable as I have never experienced any PC hang or blue screen of death.

The only deficiency is lack of memory. Yesterday, I took the notebook to ACER Service to expand the memory size to 256 MB. ACER charged me HK$500 including the memory chip and servicing fee. Seems a reasonable charge.

There are just two memory slots on the chasis. Woo.. no more expansion can be done unless I scrap the ones onboard.

2005/03/29

The world's highest performance DNS Server

Nominum has rolled out probably the world's highest performance DNS server called Authoritative Name Server (ANS). A test was conducted to compare the performance of ANS with Bind 9.3.0 using same hardware platform :

OS : Red Hat Enterprise Linux 3.0
CPU : Intel XEON 2.4 GHz processor
Memory : 2 GB RAM
HD : 160 GB Raid 5 Hard disk
NIC :Gigabit Ethernet Interface.

Bind 9.3.0 failed to load 50 million records. When the records were reduced to 10 million records, it took 150 seconds to load them to memory.

With 200M records loaded, ANS started in less than 1 second, answered 45,135 queries per second with an average latency of 0.0016 seconds.

Nominum ANS is also designed to support update of zone records on the fly, that is to say, no need to shutdown and restart the name daemon.

2005/03/28

Funny Words of Bit Torrent

The following funny words of BT are great. A comprehensive list can be found at Azureus.

Peer: a person who is participating in file sharing. that is, a person who is transferring a file using p2p technology.

p2p: is short for Peer to Peer, which is a technology to do with personal file sharing, which includes the like of BitTorrent, Gnutella, eDonkey, etc. Peer to Peer networks differ from other filesharing networks in that there is no single centralized server.

Seed: a person who is uploading a file or files to others in the swarm. A seed is a peer who has 100% of the torrent, and is uploading to other peers. Seed is also used as a verb, as in "I'm going to be seeding this file overnight", meaning leave it open and available for other users to download. Usually, a person with the whole file is a 'seed', while someone with a partial amount is a 'peer'.

Leech: a person who downloads a file using p2p technology, and who does NOT share with others when in posession of the complete file. Normally in BitTorrent, it is polite and considerate to leave your connection open long after you finish downloading, (to seed) so that other peers in the swarm who do NOT yet have the complete file can benefit from you sharing, as you have benefitted from sharing yourself when you originally downloaded the torrent. Some share more, some share less, but a leech is somebody who closes their connection as soon as they have downloaded the complete file.

Tracker: a tracker is a special server that contains the information needed for peers to connect to other peers. Trackers coordinate the BitTorrent clients, and also keep track of statistics and verification information for each torrent. Azureus contains it's own built-in tracker, but there are a variety of other tracker software packages in use. If the tracker server goes down and you try to start a torrent, you won't be able to connect to the swarm. Usually tracker errors are temporary, so Azureus will keep trying to connect until successful or the torrent is removed.

2005/03/27

10G WAN/LAN Equipment

10G WAN/LAN equipment are now being roll-out in the market.

10G Ethernet switches are important to build high speed LAN backbone. Some IBM PC workstations already have built-in GE interface. To avoid any bottleneck in such a LAN environment, it is logical for the LAN backbone boosted to 10G transmission capacity.

For 10G routers, they are definitely needed by ISPs for peer-to-peer IP connection or for connection to Internet Exchange points.

2005/03/26

Control M nuisance

DOS editor and Windows notepad use carriage return (Control M) and new line (Control J) for ending a line of text. This is the notorious Control M nuisance when using Windows editor to type Unix/Linux scripts or C program codes.

One way to stripe off the Control M is to use ascii transfer to ftp the prepared file to the Unix/Linux box. Another method is to use vi to replace Control M by null character. To me, I prefer the ftp method which is easy and straight forward.

2005/03/25

TCPView

TCPView : 一個可以檢查級及時監測出你的電腦上哪些軟體,正透過哪一個PORT,連線到到哪個 IP,如此可防止或檢查出不明的程式正透過網路將你的資料偷偷傳送出去(TCP&UDP).

2005/03/24

Staying in Singapore

I am preparing this blog message from an Internet cafe in Singapore.

I have been here for 4 days for attending a training workshop on ultra-wideband. There is a LAN plug in my hotel room but unfortuntalety Hotel Furama asks me to pay S$25 per day. I don't think this is a resaonable charge. I do have a notebook PC with me, but unusable for checking email. Without Internet access, I feel I am completely isolated from the world.

It's good to find an Internet cafe nearby. It just charges me S$2 per hour.

2005/03/21

Microsoft VPN Client



The VPN client bundled in Windows 98 and ME can only support PPTP for encryption in a data tunnel. PPTP only allows data encryption after user authentication. No doubt to say that the security level of PPTP is much worse than L2TP/IPSec.

In Windows XP, Microsoft has made the built-in VPN client capable of supporting both PPTP and L2TP/IPSec. A piece of good work by Microsoft.

2005/03/19

銀行加息

望穿秋水,終於等到銀行將儲蓄利率由 0.01 厘調高至 0.25厘。

其實,香港已有6 次沒跟美國加息,累積幅度達1厘半,皆因香港資金過多所累。冀望今安有 4-6 次加息機會,老實說,0.01 厘的息率簡直就是侮辱。

2005/03/17

Boney M


Boney M 將於明晚 (18-3-2005) 於 HKCEC演出。真佩服主辦者的勇氣,居然找來過時已久的Disco霸主,我不敢想像門票銷路,畢竟 Disco 音樂已沒落了近 20 年。

印象中 Boney M 的成名作是 Daddy Cool,繼而再有 Ma Baker, Sunny ,Rasputin 等,節柏強勁,每首都是一流的跳舞歌曲。偶然番聽這些歌曲,心情亦變得輕快。

2005/03/16

Azureus



Azureus is the most powerful BT client I have ever used. It runs with JAVA. Sun Java JRE should be installed first before one can install Azureus.

I found that too many connections could slow down the machine to a large extent. It is better to use Azureus at mid night when no other applications are required.

2005/03/14

WNTIPCFG

The program winpcfg is removed in Windows XP. To check the IP address on the NIC, one has to go to DOS mode to enter "ipconfig/all". Hmmmm, too much trouble.

In that case, WNTIPCFG can be used, download avialable from microsoft.



One thing to note is that ipconfig can display IPv6 addresses whereas WNTIPCFG can not.

2005/03/13

Volume of reported spam email in a week

According to spamcop.net, the number of reported spam email in the last week was 18,457,482. The top 200 IP addresses sent out 696,640 spam messages. Actually 18 millions a week is far too low. Many who suffer from email spam do not want to report at all.

To strengthen my capability in combating spam email, all the top 200 IP addresses are now banned from sending any email to my mail server.

2005/03/12

WinSCP



WinSCP is a simple scp client for file transfer in secure mode. The interface is quite similar to a normal ftp client such as ws_ftp LE. Very easy to use !

Interesting, there is no need for the server to run any plain ftp daemon such as wu-ftpd. All that is needed is to start sshd, running on port 22.

WinSCP supports both SFTP or SCP mode. For the former, the ftp server must run a secure ftp daemon such as vsftpd.

2005/03/11

Ostrosoft Internet Tools



A must-have networking tool if you are interested in network monitoring, port scanning, traceroute, ping and others. The download has hit 5 million since 1996.

The author reminds users with this note :

OstroSoft Internet Tools is not intended for hacking purposes, malicious attacks on networks and systems connected to the network, and other unlawful actions. Please remember - Internet is the best thing ever happened to mankind. Do not damage it.

2005/03/10

nslookup

Surprise ! Nslookup is available in Windows XP. This is a great tool for those who want to check and play with DNS.

It works in text mode at command level. The commands are very difficult to learn and remember.

2005/03/09

Froogle

Google has now released Froogle, a search engine designed to find products for sale online. Search results include price, brand, description, and, if available, a photograph.

From Froogle web site, it says that whenever Google comes across a page that appears to be sell something, it feeds the information it collects to Froogle. Vendors don't pay to have their products included in Froogle's search results.

Froogle is an indispensable tool for online shopping.

2005/03/08

PRTG



I managed to play with PRTG, a traffic grapher on Windows XP. It can be used to monitor bandwidth utilization or packet loss.

Last time I failed to make PRTG work because I was not aware that there is no SNMP installed by Windows XP by default.

The free version only allows one sensor. Presumably, most people will dedicate the single sensor to the network interface card for the purpose of monitoring bandwidth usage.

2005/03/07

cdex



Whenever I need to convert CD songs to MP3 files, I use Cdex. The current version is 1.5, released since September 2003. Though there has not been new updates for a long time, Cdex has all the functions I need. The interface is simple and easy-to-understand.

2005/03/06

Asus Vento 3600 Case

今天在高登商場,發現了鮮紅色的華碩 Vento 3600 特大機箱,外型殊不簡單,售價高達 HK$1600元。跟 Sales 研究及談論,此款設計目標是要令機箱溫度維持在38度,前面兩個排氣糟的尺寸十分誇張,display card 位置有一把大風扇加強散熱,極之適合作 game station

這是一個非常高檔的產品,但我對這龐然大物絕不感興趣。

2005/03/04

Linare Desktop PC

I come across Linare web site and found the price of Linare desktop PC surprisingly low.





This PC is installed with Linare OS, packaged with OpenOffice1.1, Internet tools, graphic viewers, multimedia players. I don't know the Kernel version, but I believe it should be 2.4 or higher.

Would it be possible to buy such a PC here in Hong Kong ? No way !!

2005/03/03

董建華辭職

直覺上董建華不是自願辭職,他是政治鬥爭下的犧牲品。

特首接班人現在已是呼之欲出,還有誰有膽量與大熱門兢賽。

2005/03/01

Java popup in Firefox

Yesterday, I encountered popups when using Firefox browser. The popups were written in Java language.

By default, Firefox can bar ActiveX and VB scripts from being executed. Badly, it is not practical to stop Java scripts from being executed otherwise a large number of web pages can not be properly displayed.

Though Firefox is affected by Java popups, on balance, there is still less trouble caused to end users compared with Micrcosoft Internet Explorer.