|  CrazyHorace | Aug 16, 2006 10:25pm | How does a subnet work?
I have a "friend" that has an embarrassing problem... his network is too large and he's running out of IP addresses. He has a 192.168.1.x network, and I understand that he could put some machines on a 192.168.2.x network but he would need a router between the two... however, I also believe that through subnet masking he can make all the machines (on both networks) communicate as if on the same network, so that they can still use network printers, and one password authentication server, etc. How do you make subnet masks work?
First, a bit about IP subnetting. With your IP address, you have a subnet mask. This subnet mask determines which IP addresses are located on your local network. You also have a default gateway, which is the network device (typically a router or firewall) that the machine knows to contact for any machine that is not on the local network. The most common subnet mask on private networks is 255.255.255.0, which means the last octet of the IP address, like 192.168.1.X above, can be 1 through 254. This means once you get above 254 devices on your network, you run out of address space on a network using a 255.255.255.0 subnet mask.
At this point, your options are to either change your subnet mask, or put in a router. Which is most appropriate depends on plans for network growth. In a fast growing network, or one with a significant amount of network traffic, a layer 3 switch (a switch that acts as a very fast router) is the most appropriate choice. In a network that won't get many more than 275-300 hosts and doesn't have a whole lot of network traffic, using a larger subnet mask is an acceptable choice. To increase the number of IP's on the subnet, change the subnet mask on *all* hosts to 255.255.252.0, while still using the same IP addresses. Make sure every single host gets changed, or you will have communication issues. With a 255.255.252.0 mask, your network will now range from 192.168.0.0 through 192.168.3.254. There is substantially more to IP subnetting and network design than could possibly be described here. Inappropriate subnetting and design can lead to severe network performance problems, so I strongly suggest if you don't have expertise in this area that you contact a qualified network consultant experienced in enterprise network design.
Suggested resources:
  
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Sponsor |  Thlayli | Aug 18, 2006 8:48am | | Wow, scrape the ugly off that post and it's pretty useful. :p |
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Sponsor | | ChicagoDad | Aug 20, 2006 9:02pm | How to Go Wireless indows XP should show an icon with a notification that says it has found a wireless network. 
MORE HERE : windowsmarketplace.com/Content.aspx [windowsmarketplace.com/Content.aspx]
A step-by-step guide to setting up a wireless network at home Tony Northrup Published January 2005  You can use a wireless network to share Internet access, files, printers, and more. Or you can use it to surf the Web while you're sitting on your couch or in your yard. Plus, it's easier to install than you think. There are 4 steps to creating a wireless network. 1. Buy your wireless equipment 2. Connect your wireless router 3. Configure your wireless router 4. Connect your computer to the wireless network
How to Go Wireless * Wireless router * Wireless network adapter * * Wireless router * Wireless network adapter * D-Link * Netgear * Linksys * Microsoft * Buffalo * USB hub D-Link * Netgear * Linksys * Microsoft * Buffalo * USB hub
Windows XP Service Pack 2 is not required for wireless networking, but it does make things much easier. Service Pack 2 also helps protect you against hackers, worms, and other Internet intruders. To install Service Pack 2, visit Microsoft.com/protect.
. Connect your wireless router Since you'll be temporarily disconnected from the Internet, print these instructions before you go any further. First, locate your cable modem or DSL modem and unplug it to turn it off. Next, connect your wireless router to your modem. Your modem should stay connected directly to the Internet. Later, after you've hooked everything up, your computer will wirelessly connect to your router, and the router will send communications through your modem to the Internet. 
If you currently have your computer connected directly to your modem: unplug the network cable from the back of your computer, and plug it into the port labeled Internet, WAN, or WLAN on the back of your router. * If you do not currently have a computer connected to the Internet: plug one end of a network cable (included with your router) into your modem, and plug the other end of the network cable into the Internet, WAN, or WLAN port on your wireless router. * If you currently have your computer connected to a router: unplug the network cable connected to the Internet, WAN, or WLAN port from your current router, and plug this end of the cable into the Internet, WAN, or WLAN port on your wireless router. Then, unplug any other network cables, and plug them into the available ports on your wireless router. You no longer need your original router, because your new wireless router replaces it.  Next, plug in and turn on your cable or DSL modem. Wait a few minutes to give it time to connect to the Internet, and then plug in and turn on your wireless router. After a minute, the Internet, WAN, or WLAN light on your wireless router should light up, indicating that it has successfully connected to your modem. 
s a quick reference, this table shows the default addresses, usernames, and passwords for some common router manufacturers. Router Address Username Password 3Com 192.168.1.1 [192.168.1.1] admin admin D-Link 192.168.0.1 [192.168.0.1] admin (leave blank) Linksys 192.168.1.1 [192.168.1.1] admin admin Microsoft Broadband 192.168.2.1 [192.168.2.1] admin admin Netgear 192.168.0.1 [192.168.0.1] admin password Internet Explorer will show your router's configuration page. Most of the default settings should be fine, but you should configure three things: 1. Your wireless network name, known as the SSID. This name identifies your network. You should choose something unique that none of your neighbors will be using. 2. Wireless encryption (WEP) or Wi-Fi Protected Access (WPA), which help protect your wireless network. For most routers, you will provide a passphrase that your router uses to generate several keys. Make sure your passphrase is unique and long (you don't need to memorize it). 3. Your administrative password, which controls your wireless network. Just like any other password, it should not be a word you can find in the dictionary, and it should be a combination of letters, numbers, and symbols. Be sure you can remember this password, because you'll need it if you ever have to change your router's settings. The exact steps you follow to configure these settings will vary depending on the type of router you have. After each configuration setting, be sure to click Save Settings, Apply, or OK to save your changes. Now, you should disconnect the ne |
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| | CrazyHorace | Aug 20, 2006 9:22pm |  Secure Your Wireless Device or Network ![]() ![]() ![]() netsecurity.about.com [netsecurity.about.com]">ArchiveArticles and information on the various wireless protocol implementations- Bluetooth, 802.11b, 802.11g, etc.- and the vulnerabilities they present along ...
netsecurity.about.com/od/secureyourwifinetwork/
Top 9 Tips for Wireless Home Network SecurityFrom Bradley Mitchell,
Your Guide to Wireless / Networking.
FREE Newsletter. Sign Up Now! Many folks setting up wireless home networks rush through the job to get their Internet connectivity working as quickly as possible. That's totally understandable. It's also quite risky as numerous security problems can result. Today's Wi-Fi products don't always help the situation as configuring their security features can be slow and non-intuitive. The recommendations below summarize the steps you should take, in order to importance, to improve the security of your home wireless LAN.1) Change Default Administrator Passwords (and Usernames)At the core of most Wi-Fi home networks is an access point or router. To set up these pieces of equipment, manufacturers provide Web pages that allow owners to enter their network address and account information. These Web tools are protected with a login screen (username and password) so that only the rightful owner can do this. However, for any given piece of equipment, the logins provided are simple and very well-known to hackers on the Internet. Change these settings immediately.2) Turn on (Compatible) WPA / WEP EncryptionAll Wi-Fi equipment supports some form of "encryption." Encryption technology scrambles messages sent over wireless networks so that they cannot be easily read by humans. Several encryption technologies exist for Wi-Fi today. Naturally you will want to pick the strongest form of encryption that works with your wireless network. To function, though, all Wi-Fi devices on your LAN must share the identical encryption settings. Therefore you may need to find a "lowest common demoninator" setting.3) Change the Default SSIDAccess points and routers all use a network name called the SSID. Manufacturers normally ship their products with the same SSID set. For example, the SSID for Linksys devices is normally "linksys." True, knowing the SSID does not by itself allow anyone to break into your network, but it is a start. More importantly, when someone finds a default SSID, they see it is a poorly configured network and are much more likely to attack it. Change the default SSID immediately when configuring your LAN.4) Enable MAC Address FilteringEach piece of Wi-Fi gear possesses a unique identifier called the "physical address" or "MAC address." Access points and routers keep track of the MAC addresses of all devices that connect to them. Many such products offer the owner an option to key in the MAC addresses of their home equipment, that restricts the network to only allow connections from those devices. Do this, but also know that the feature is not so powerful as it may seem. Hacker software programs can fake MAC addresses easily.5) Disable SSID BroadcastIn Wi-Fi networking, the access point or router typically broadcasts the network name (SSID) over the air at regular intervals. This feature was designed for businesses and mobile hotspots where Wi-Fi clients may come and go. In the home, this feature is unnecessary, and it increases the likelihood an unwelcome neighbor or hacker will try to log in to your home network. Fortunately, most Wi-Fi access points allow the SSID broadcast feature to be disabled by the network administrator.6) Do Not Auto-Connect to Open Wi-Fi NetworksConnecting to an open Wi-Fi network such as a free wireless hotspot or your neighbor's router exposes your computer to security risks. Although not normally enabled, most computers have a setting available allowing these connections to happen automatically without notifying you (the user). This setting should not be enabled except in temporary situations.7) Assign Static IP Addresses to DevicesMost home networkers grativate toward using dynamic IP addresses. DHCP technology is indeed quick and easy to set up. Unfortunately, this convenience also works to the advantage of network attackers, who can easily obtain valid IP addresses from a network's DHCP pool. Turn off DHCP on the router or access point, set a fixed IP address range, then set each connected device to match. Use a private IP range (like 10.0.0.x) to prevent c |
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| | TheBlackHawk | Aug 21, 2006 3:09pm | As seen on Tech TV:APPS: You have to have:
 SG TCP Optimizer  TCP Optimizer Description: The TCP Optimizer is a free, easy Windows program that provides an intuitive interface for tuning and optimizing your Internet connection. There is no installation required, just download and run.
The program can aid both the novice and the advanced user in tweaking related TCP/IP parameters in the Windows Registry, making it easy to tune your system to the type of Internet connection used. The tool uses advanced algorithms, and the bandwidth*delay product to find the best TCP Window for your specific connection speed. It provides for easy tunning of all related TCP/IP parameters, such as MTU, RWIN, and even advanced ones like QoS and ToS/Diffserv prioritization. The program works with all current versions of Windows, and includes additional tools, such as testing average latency over multiple hosts, and finding the largest possible packet size (MTU).
The TCP Optimizer is targeted towards broadband internet connections, however it can be helpful with tuning any internet connection type, from dialup to Gigabit+ :)
If you need help with the program, check the TCP Optimizer documentation, read our broadband tweaking articles, the Optimizer FAQ, and/or visit our Forums. Mirrors:
SpeedGuide.net (recommended)
Download.com
MajorGeeks.com
Softpedia.com
The legacy unsupported version 1 of the Optimizer is still downloadable from -here-. OS:  Windows 9x/ME/2K/XP/XP-SP2/2k3 | version: 2.0.3 | date: 01/06/2006 | filesize: 596 KB |
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| | SickBastard | Aug 22, 2006 1:49am | Dan "Tweak Monkey" Kennedy Before e-mailing, please consult the forums for additional support. Don't throw out that old PC yet! A fine-tuned Windows XP PC can run quite fast even it's seriously lacking in the memory and CPU department. Before you chuck out your PC to buy a new one, try stripping some of the rust that's built-up over the years; the results may surprise you. It's probably your operating system that's slow, not the PC. It's software, not hardware - you know, invisible 1s and 0s held in an electric field representing your data. Your computer is still fast, but there's a ton of stuff slowing it down. There's more 1s where there should be 0s and your PC is killing itself fighting an impossible battle to burn off this fat. We've seen Pentium II machines with 128 MB RAM run XP faster than Pentium IVs with 4x the clock speed and 4x the RAM - so what gives? This article will help you figure out why your PC is running slow and outline exact steps to fix it quickly, before throwing in the towel with a format, restore, or new PC purchase.
The Culprit - What Slows Down Your PC Before you dive into your PC, it is absolutely critical that you determine what is slowing it down. Ignoring a bad hard drive could lead to catastrophic damage with data loss. Lack of sufficient RAM completely limits a PC's performance. Spyware and malware could be having a circus inside your OS - just like in 90%+ of other PCs online. There are other causes for PCs to run slow, but these are the most common. The basic symptoms of a bad hard drive are: extremely slow performance, blue screen of death error screens, system errors on startup, and strange sounds coming from your PC, especially clicking sounds. If you suspect your drive is failing, shut down your PC as soon as possible. Download Hitachi's DFT, burn a CD to test your drive, boot off it, and run a scan to determine if it's defective. If you use a bad hard drive for too long you might suffer complete data loss. It's possible your PC doesn't have enough RAM. The amount of RAM your PC has can be checked by hitting the Windows and Pause/Break keys at the same time. The amount is listed toward the bottom right. The same information can be accessed by right-clicking My Computer and choosing Properties. We've seen Windows XP run with 64 MB RAM and it is not pretty. With 128 MB, an XP machine can survive basic tasks as long as there is not a lot loaded into memory. We consider 256 MB to be the absolute tolerable minimum. The jump to 512 MB will help speed up the PC considerably, especially if there is antivirus or anti-spyware software running in the background. Currently 1024 MB (or 1 gigabyte) seems to be the sweet spot, where adding more RAM doesn't seem to be cost effective for most users. However, gamers can usually benefit from the jump to 2 GB. RAM is cheap. Check your local retail ads for sales. Seriously consider upgrading if your PC has less than 512 MB. Instructions on installing RAM can be found here. Instructions are available for notebooks here. You might avoid spyware like a flagged minefield. But if kids, friends, or PC newbies are using your PC to browse the Internet it's very likely that your PC is infected. The basic symptoms of spyware, malware, adware are: slow performance, pop-up ads, strange error messages, extra toolbars in your browser, frequent web browser crashes, and slow or completely non-functional Internet. Completely removing spyware can be a big job. If you're not up for it, you may want to pay a repair shop to complete the job for you. To remove spyware, here's our most recent guide. Our older guide is available here. If all of these other things are not the problem, your PC is probably just cluttered with crap and needs a tune-up. This article covers a quick (5-15 minute) tune-up for Windows XP. The basic approach: Visual effects, Add/Remove Programs, Startup folder, temp files, registry cleaning, CCleaner, services, then defragment. Shown below is the before and after CPU usage from a typical tune-up of this type. The PC tested here started with 42 processes using over 152 MB of memory. After the tune-up, this was dropped to 23 processes using only 63 MB of memory. Before:After:   To see your current CPU and memory usage, hit CTRL-ALT-DELETE and view the Performance tab. The number of processes is listed in the bottom-left corner.
Step 1: Stripping off the Rust The visual effects, that is animations, shadows, and extra Windows XP polished interface, eat up CPU and memory (especially on older PCs). Hit the Windows and Pause/Break keys or right-click My Computer and choose Properties. Navigate to the Advanced tab, then click the first Settings box. Very slow (<500>- Animate Windows when minimizing and maximizing
- Smooth edges of screen fonts
- Smooth-scroll list boxes
- Use drop shadows for icon labels on the desktop
If you plan to use Common tasks (such as the built-in Windows Explorer CD Burning Utility, you may want to leave Use common tasks in folders enabled. Read through this list and determine what else you may want. Test the settings using the Apply button before deciding you're OK with changes. Turn off your background image and you'll notice the desktop comes up slightly faster. It also (depending on the detail of the image) will give you more free memory. This can be accessed by right clicking the Desktop, choosing Properties, Desktop, and looking under Background. 
Sure, it looks plain. But it helps a bit with resources. To further tweak the visual settings for maximum performance
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| | CrazyBastard | Aug 22, 2006 7:43pm | What is a MAC address and why would you want to change it?dukelupus.pri.ee/simplemac.php [dukelupus.pri.ee/simplemac.php]
MAC stands for Media Access Control. A MAC address is a 48-bit hexadecimal number (12 characters), that is assigned to a networking device, such as a network card, when it is manufactured. It is also known as a hardware address, MAC-layer address, adapter address, Ethernet address, burned-in address and physical address. A MAC address uniquely identifies every network component; the first six numbers comprise the Organizational Unique Identifier and are assigned by the IEEE, the last six represent the interface serial number MAC addresses are usually written as six groups of characters; normally they look something like 00:DE:AD:BE:EF:01 or 00-DE-AD-BE-EF-01. However, this is for human convinience only, in hardware it is 00DEADBEEF01. Note that MAC address - in many networks it allows you to access it if you don't have an "acceptable" MAC address. Now why would you want to change your MAC address? Well, for one thing, many ISP's identify computers by MAC address and allow net access only for computers that are in their database. Now imagine that you've changed your NIC (Network Interface Card) or bought a new computer. If you're lucky, your ISP will ask you to pay a pile of money, upon which they will change their database in ten seconds - allowing you access. However, if it is Friday evening and "Tech Support" have all gone home ... you won't be able to access the network until Monday. Also, imagine you visit a friend and want to quickly check your e-mail with your laptop. You can, of course, reconfigure his e-mail program -- or you can simply change the MAC address of your laptop to match the one of his PC and plug in the network cable. Voila! Last, but not least - in current times when RIAA millionaires and their associates hunt people down for sharing files, many lawsuits or messages to ISP's are filed using MAC addresses. If you have a dynamic IP and you can stay connected with non-original MAC address, your chances of getting caught are greatly disminished. All of the above are the reasons why I made SimpleMAC - a user-friendly and free utility for changing MAC addresses. Note the "free" part - when I needed to change the MAC address, I found just two commercial utilities for that, both $20. I made SimpleMAC in about 1.5 hours - and that includes time spent for making the splash screen and figuring out how to access WMI from Delphi. If you think that my work is worth $20 a piece, well, who am I to say no to the money. ;) Note that quite a lot of modern network cards also support MAC cloning, i.e. changing the MAC address from the driver. I'll give a small example of this towards the end of this page.
Using SimpleMAC Download SimpleMAC.exe and start it. There is no installer, just the .exe.You will get the small splash screen for few seconds (the program needs some time to query your hardware configuration; you can bypass this step, see "Command line options") and then main program window will open:  As you can see, the main window mirrors the program name - it is simple and user-friendly. You can ignore the second Packet Scheduler Miniport - it is a virtual device created by Windows. - Number is assigned by Windows to every networking device. Of course, Windows uses 0001, 0002, etc. NOTE! See the asterisk next to '9' (NVIDIA nForce Networking controller, selected in the picture). This means that the MAC address of that device is changed and does not use MAC address stored in the hardware.
- Description is the name of the device, either named by Windows or stored in hardware.
- MAC address is, of course, the MAC address of the device.
- The Set Button assigns the new MAC address to the selected device - the new address is specified in the editboxes.
- The Reset Button resets the software-assigned MAC address to the default (i.e. that stored in hardware).
Note that all MAC address changes only become active after rebooting your computer. You can also enable/disable NIC but apparently that does not always work. You can verify that the MAC address has been changed by opening a command window (go to Start->Run and type CMD in the dialogue box) and typing "ipconfig /all" (without the quotes). Your current MAC address is shown as "Physical address". Note that you can also identify your NIC that way (it is shown as "Description"). As a rule, you will want to change only the MAC address of your network card, but not the WAN miniport or some other device. If therefore you cannot identify your NIC by name, look for it by double clicking on its entry in the list. A new p |
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