In order to keep closer contact with IT network administrators in Macau, we've created a network admin newsletter and I've taken the liberty to add you to our netadmin-news mailing list. If you'd like to unsubscribe or recommend friends to subscribe at any time, just email me.
--- Simon Tam, Chief EditorIf you want to share a folder in Windows XP, 2000, 2003, first of all, you need to be the memeber of "Power Users" or "Administrators" group (in workgroup envirnoment) ,or, "Server Operators" or "Administrators"(in domain envirnoment). If not, when you right click a folder, you will not see the "Sharing and Security" option.
One more reason will make this option disappeared:
Yesterday, one of my student encountered this problem, he logged on the Windows XP as Administrator account but still could not see this option. Why?
Finally, we found out that the "Server" service on that computer was stopped. This service provides file and print sharing service. Without it, you cannot share any folder or printer. Beware.
Suppose that one user in the remote office do not know how to plot a graph in Excel, he is using Windows XP, and you are the IS support engineer. You need to help him to achive this task. You may need to go to the remote office to teach him cause on the phone, it is difficult to teach him how to do it. But, actully, you can help him on your computer!
You can ask that user to send you an email by using Remote Assistance (just a few steps). With this email, you will get a link to log on to his computer and share his desktop between you and him. Then, you can demonstrate to him how to do it.
Even powerful, you can initiate the Remote Assistance session yourself. That user just needs to approve your connection.
Cool or not? Of course there should be IP layer connection between the two offices and the firewall, if any, needed to be configure to allow Remote Assistance traffic, just TCP port 3389, cause Remote Assistance is based on Remote Desktop Protocol.
To learn more, see : http://www.microsoft.com/technet/prodtechnol/winxppro/maintain/rmassist.mspx#ENHAC
Iptables is widely used in Linux firewall. It's used in Cyberlab for firewall and to protect server itself also. It helps to protect the network to prevent attack. For analysis purpose, we asked the iptables to log down all dropped packets.
Serveral months ago, some computers in the classroom in Cyberlab were infected by virus. Infected computers kept broadcasting huge numbers of udp packets to try to attack the server in the network. Iptables works perfect to prevent the attack from the infected computers. However, the number of dropped packets were too many. The firewall blocked all attack packets and logged all of them. The logging process used up the resources of the firewall.
To prevent this happen again, we limit the logs in iptables by adding --limit options in the iptables log entry. The following entry is put in the last of FORWARD chain. It will log everything which not ACCEPT in the upper entries. It won't log the packets if there are more than 14 packets per minute.
iptables -A FORWARD -m limit --limit 14/min -j LOG --log-level 7
CPTTM will host a VPN training Course in November. You will learn how to setup and manage SSL VPN using OpenVPN. Cisco and Netscreen solutions will also be intruduced.
For details of the course, please visit our course web site.
http://www2.cpttm.org.mo/training/sdb/showCourse.do?courseCode=CM248-09-2006-C
This book aims to help you get ready to take - and pass - the CISSP exam. It helps you understand and appreciate the subjects and materials you need to pass the exam. This book is aimed strictly at test preparation and review. It brings you as much information as possible about the CISSP exam.
You can
borrow this book from the CPTTM
IT Book Shelf at Cyber-Lab.
Archive of the CPTTM Network
Admin Newsletter is available at http://www2.cpttm.org.mo/cyberlab/netadmin-news.