One of the way to secure a Cisco router / switch is to encrypt password in it.
In order to encrypt passwords that are saved in the Cisco devices configuration file, you may use the “service password-encryption” global configuration command.
This command should be used as a simple cipher to prevent unauthorized users from viewing the passwords in router / switch configuration file. It is not against someone who obtains a copy of the router / switch configuration file as some software instantly can decode any passwords encrypted with the MD5 encryption scheme.
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Tags: Cisco, encryption, Password, router, switch
There are two modes of operation in Windows 2003 environment. Basically a computer can work as workgroup computer or domain computer. Most home and small business environments will be Workgroup, and most enterprise businesses will run in domain mode.
Basically when you install Windows 2003 server, by default it is a workgroup computer. Workgroup environment is suitable for a limited number of computers (usually no more than 10 computers) in close proximity. However, if the number of computer is huge, it is advisable to join individual computer into domain.
In Workgroup environment, each computer store ID and password locally. There is no centralized management in this case. A user needs a user account on each computer that he/she requires access. This means, if a user needs to access to several computers in the network, each of this computer will need to have the ID and password of the user store locally. It is not an easy task for administrator if there are many computers need to be managed and configured. It may take up a lot of time to just setting up account in various PCs for a new user. Changes to user accounts, such as changing a user’s password or adding a new user account, must be made on each computer in the workgroup. As a result, passwords can become out of synchronization, if changed happened on one computer and not others.
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Tags: computer, domain, network, Password, server, windows, windows2003, workgroup
Here is a simple howto on adding windows 2003 computer to a Windows Server 2003 domain. This should be valid for other version of windows client computers too.
Before performing the following steps, make sure that your computer can reach the domain controller through the network. You may use ping to test if your computer can communicate with the domain controller.
First of all, right-click My Computer, and then click Properties.
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Tags: domain, domain controller, join domain, Microsoft, ping, windows, windows2003
This is a quick fix to vmware network virtualization.
Sometime while using vmware, your guest virtual machine may face the problem with network connectivity. I have this problem with two of my virtual machines the other day. Only one of the virtual machines is able to connect to the network. (By the way, both are created using same image) After trouble shooting for a while (such as changing the physical address of Ethernet, restarting it, or changing the network type to bridge or host-only networking and so on), I decided to add in an extra network interface to one of the virtual machine. After that I removed the existing Ethernet interface from it. Surprisingly these steps solved my problem.
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Tags: ethernet, network, network interface, network problem, Networking, physical address, virtual machine, virtualization, vmware
CamStudio is a software which I use to record all screen activity on my computer for use in software demonstrations and presentations.
Before discovering this freeware, I use Jing most of the time in recording video of what I do. However, one disadvantage with Jing is it only generate Streaming Flash video (SWF) file. As I always use Microsoft Movie Maker in editing video, this format is not supported. CamStudio easily create industry-standard AVI video files and using its built-in SWF Producer can turn those AVIs into lean, mean, bandwidth-friendly SWFs.
I have created a video on How to create new user account in XP using CamStudio. It was perfectly recorded. However, after uploaded to Youtube, somehow the quality of the video is not comparable to the original video. Still need time to find out the reason & how to overcome it.
Let me know if you have any advice on overcome this problem.
Tags: AVI, freeware, Microsoft, movie, record, software, SWF, video
In my previous post on Static route configuration, I have touched on some basic of static route configuration. In this post, I will show you more details on how to configure static routing in Cisco devices.
IP routing is enabled on Cisco routers by default. If it has been previously disabled on your router, you can turn it on in config mode with the command ip routing.
Router0(config)#ip routing
Router0(config)#ctrl-Z
For routers to send or forward packets to networks that are not directly connected, they must know the path to reach the destination network. This information can be manually configured in router by network administrator — the use of static routes. The router can also learn routes information by using a dynamic routing protocol. Anyway, static route is much easier to be configured. However, it provides very little fault tolerance or ability to discover new routes as the network changes.
As mentioned in my previous post, static routes are hard-coded on a router or switch. They tell the network device exactly where to send traffic, no matter what. It is a very quick and effective way to route data from one subnet to another subnet although it does not scale well in large network.
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Tags: Cisco, Cisco IOS, ip route, ip routing, network, router, static route, switch
It is good to have CCNA credential if you would like to work as a network engineer. It shows that you have the basic foundation in the area of networking especially in the field of Cisco networking. Frankly, it would be easier when you are marketing yourself for a new IT job if you have this certification. Having CCNA may demonstrate that you are keeping up with technology. This is something important.
According to Cisco Systems,
The Cisco CCNA network associate certification validates the ability to install, configure, operate, and troubleshoot medium-size routed and switched networks, including implementation and verification of connections to remote sites in a WAN.
At a minimum, CCNA should have a basic understanding of the TCP/IP network technology, know how to configure Cisco IOS, Cisco access list, routing - static route and dynamic routing and install Cisco router, switch and even operating LAN and WAN.
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Tags: CCNA, Cisco, Cisco Access list, Cisco IOS, Cisco router, network, routing, static route
One of the most important tasks of a network engineer or network manager is to manage his / her network. And one of the important items in network management is network monitoring. Through network monitoring, a network engineer will be able to know how his network perform - whether it is over utilized or under utilized. Based on this information, s/he will be able to plan for the network s/he manage.
I used to use MRTG in managing my network. As long as the network nodes - Cisco router, Cisco switch, server is having SNMP service enabled, it should be able to be monitored by MRTG. Not only MRTG can show us how much incoming and outgoing traffic through each of the network interface of a network node, we also can use an external program to gather data which should be monitored via MRTG.
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Tags: Cisco, Cisco router, MRTG, Network Management
Whether it is a Windows PC, Cisco router, switches, Linux machine or network enable device, it is recommended to stop unnecessary services that are run by default. Every running, but unused, service on your system maybe a possible means of attack. Users may not even be aware that many of these services are running.
It is important to know the security implication of any network service before enabling it in. For example, a telnet client running on another device on the network can easily establish a telnet session to a system where telnet service is enabled; it needs only the IP address of the system and the port or socket number of the network service running on the system. The rule of thumb for TCP and UDP ports is: Turn off any services or listeners that you do not need for your application to function. One way to check the list of ports running on your system is to go to one of the many web sites that can run a remote scan of your system and tell you how secure the system.
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Tags: Cisco, firewall, network service, port, security risk
Following are the steps to attach photos or files in your email and send it to your friends. I will use Hotmail in this case.
Step 1:
In Hotmail interface, select New and compose your email. Select File from the Attach.
Select Attach in Hotmail
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