Create a Wireless Home File Sharing Network

Introduction

A DHCP capable wireless router can be used as a wireless media 'server'. Each PC can see each other's sharable folders. Music, video and pictures can be streamed from the main PC via the router to any authorized PC/laptop etc in the house.

Steps

For a full-blown file sharing network with easy access straight from boot up, the following five steps are required:

1. Workgroups
2. Sharing Folders
3. Configuring Firewalls
4. Mapping Network Drives
5. Customized O/S's

1. Workgroups

Configure all PC's to belong to the same workgroup. This streamlines access issues.

• Under {Control Panel / System / Computer Name / Change} set the workgroup to a useful name like HOME_NETWORK.

2. Share Folders

To share folders you need to access the folder properties and do two things.

• Under the Sharing tab click {SHARE THIS FOLDER}
• Under the Sharing tab also click {PERMISSIONS} and choose the permissions level. This is only necessary if you want remote admin privileges.

You do not need to edit the properties of sub-folders, the root-folder is sufficient. For security, only share a limited number of folders and definitely no system ones.

3. Configure Firewalls

Each respective firewall must allow the other PC access to the shared folders. There are two ways:

• Ensure that the Router DHCP setting is {AUTO}. Configure each firewall {TRUSTED NETWORKS}, or equivalent, to the private range issue eg 192.168.1.2 - 192.168.1.254
• Ensure that the Router DHCP setting is {MANUAL}. AT each PC, under properties for {Wireless Network Connections}, click the properties for {INTERNET PROTOCOL TCP/IP}. Enter a unique IP eg 192.168.1.X where X= 2 to 254

Configure each firewall {TRUSTED NETWORKS}, or equivalent, to allow access inbound/outbound to the other PC unique IP address. This is slightly more secure from casual poking especially if X is midrange.

Important: For security reasons, ensure that you are using maximum WPA encryption on your router.

4. Mapping Network Drives

It is always handy to map a drive letter to the shared folder on another PC.

• Open Windows Explorer
• Under {MY NETWORK PLACES / ENTIRE NETWORK / MICROSOFT WINDOWS NETWORK} click the workgroup eg HOME_NETWORK and select the PC of interest and click the shared folder required.
• Map that folder to a drive letter via TOOLS / MAP NETWORK DRIVE
• If you wish you may tick the choice for {Reconnect on Logon}

5. Customized O/S's

If you have {FILE & PRINTER SERVICES} and {CLIENT FOR MICROSOFT NETWORKS} installed, then ignore the following:

Rarely, the advanced user may have deliberately installed a custom streamlined version of windows, without some services that would have merely bloated the OS.

• Under {MY NETWORK PLACES} click the properties for {Wireless Network Connections}.
• Select {FILE AND PRINTER SHARING FOR MICROSOFT NETWORKS} and click {INSTALL}.
• Under {MY NETWORK PLACES} click the properties for {Wireless Network Connections}.
• Tick the box for {FILE AND PRINTER SHARING FOR MICROSOFT NETWORKS} and click {INSTALL}.

Do similarly with {CLIENT FOR MICROSOFT NETWORKS}

When Qos are usefull

QoS is useless if you don't have programs that use it. 99.9% of the usual software doesn't use it. Practically - if you don't know you have to install it you don't need it.

Wireless Network and Router Security Tips

Reminded by the latest Cisco security alert, many network managers do not realize that their routers can be the jump point to attack. Router operating systems are just as vulnerable to hacker mischief as network operating systems. Most medium to small sized companies do not employ router engineers, or outsource this function on a need to do basic. And because of this, network administrators, and managers, either do not know enough to secure the router or do not have time. Listed below are the 10 basic router security tips.

1. Update your router's OS. Just like network operating systems, router operating systems need to be updated to correct programming oversights, flaws, and buffer overflow issues. Always check with your router manufacture for current updates and OS versions.

2. Change the default password. As much as 80 % of security incidents are caused by weak or default passwords, (This is according to CERT at Carnegie Mellon University) Avoid using common passwords and use mixed case letters as a stronger password policy .

3. Disable HTTP configuration and SNMP. The HTTP configuration part of your router may be easier to configure for a busy network admin, but it is also a security problem for routers. If your router has a command line configuration, disable the HTTP config mode and use it. If you are not using SNMP on your router, then there is no need to have it enabled. Cisco has a SNMP vulnerability with GRE tunnel attacks.

4. Block ICMP ping requests. Ping and other ICMP functions are useful tools for both the network admin and the hacker. ICMP enabled on your router can be used by hacker to identify information to target your network for attack.

5. Disable Telnet use from the Internet. In most cases you do not need an active telnet session from an Internet interface. Access to your router's configuration is more secure if accessed internally.

6. Disable IP directed broadcast. IP directed broadcast can allow Denial of Service (DOS) attacks on your equipment. A router's memory and CPU can be maxed out from too many requests, which can result in a buffer overflow entry.

7. Disable IP source routing and IP redirects. Redirects allow packets to come in from one interface and leave by another. You don't want engineered packets to redirect to a private internal network.

8. Packet filtering. Packet filtering routes only the types of packet you want to enter your network. Many companies only allow 80 (http) and 110/25 (email). Additionally you can block and allow IP Addresses and Ranges.

9. Review Security Logs. By simply taking the time to review your log files you will see obvious patterns of attack, and or even vulnerabilities. You will be surprised to how much activity your router is subject to.

10. Unnecessary Services. Unnecessary services should always be disable, whether they are on a router, server, or workstation. By default, Cisco devices up through IOS version 11.3 offer the "small services": echo, chargen, and discard. These services, especially their UDP versions, are infrequently used for legitimate purposes, but can be used to launch denial of service and other attacks that would otherwise be prevented by packet filtering.

Troubleshooting Wireless Network Connections

In this article we will look at how to tackle some common wireless network problems that people come across. This document will outline the steps you should take if you encounter one of the mentioned issues.

Check the wires and wireless network adapter

Checking that all your wires are plugged in at the router and from the plug is one of the first things you should do – provided of course that you have access to them. Verify that the power cord is connected and that all the lights of the router and cable/DSL modem are on. This may seem like a ridiculous suggestion but you should never disregard the obvious. You’d be surprised at how your configuration can be perfect, and after a while of playing around with settings you realize that the network cable leading from the router to the cable modem has come undone slightly.

You will also want to check that your wireless network adapter is switched on. Some laptops come with a small blue or red button on the side while others require you to enable it from the operating system. In Windows, go to device manager and check that your wireless network adapter is enabled. If you have a PCMCIA or USB wireless adapter try removing it and then re-inserting it while Windows is running so it will re-detect it. The lights on the adapter give an indication of whether there is a problem. On mine, I have two lights; one is orange to signify that the PCMCIA card has power and the other is green to show if a connection has been established. A blinking green light means that I am not in range of a wireless access point or there is a problem with connectivity, whereas a stable light means a connection has been established successfully. Take a look at your device documentation as these sorts of details will vary with each product.

Driver Compatibility

It is important to make sure that you have installed the correct device driver for your wireless network adapter. This can cause all sorts of problems or your adapter not to function at all. A friend of mine recently set up his own wireless network at home but complained to me that his wireless network connection was going “crazy”. Upon inspection I realized that he had configured his router properly but installed the 5v instead of the 3v driver on his laptop PCMCIA network card. Once the correct driver was installed, everything began to run smoothly. It just goes to show how even the smallest detail can make all the difference so make sure you have the correct driver installed!

Low Signal Strength

There are a number of factors that can cause the signal of your access point to deteriorate and the performance of your network to fall under par. Practically any appliance that operates on the same frequency level (2.4 GHz) as 802.11b or 802.11g can cause interference with your wireless network. Be sure to keep cordless phones, microwaves and other electrical equipment at least 1m away from the access point. Try changing channels on the access point and test it out on one of the clients. To change the radio channel on the access point login to the configuration (usually a web based interface) and go to the Wireless Settings (will vary depending on vendor) section, select a different channel and save settings. On the client, go to Device Manager, right click your wireless network adapter and go to Properties. In the advanced tab select the Channel Property and change the Value to the same number as the one you chose on the Access Point. Disable and then re-enable the wireless connection.

Access Point Location

You may also want to try changing the position of your access point antenna to improve performance. Play around with its position and see if you notice a difference. I find that if I point the antenna sideways or downwards I have better reception on the floor below. The following images demonstrate what I mean.

Antenna pointing upwards (default)

Antenna pointing sideways

The location of your access point is vital. Try and place it in a central location, as much as possible avoiding physical obstructions and reflective surfaces. Remember that wireless signals bounce of windows and mirrors, thus decreasing the range. Experiment with different locations until you find one that is practical and promising. Most people, including myself, like placing it near the ceiling since most obstructions are nearer to the floor.

It’s always a good idea to monitor the performance of your signal by using a diagnostic utility. This will help you to identify how strong your signal is in different locations and whether other electrical equipment is interfering. Run the utility when the microwave or cordless phone is in use and see if you notice a difference. Usually your access point will come with its own monitoring utility.

Installing a repeater for a performance boost

If you’re looking for a boost you can always choose to install a repeater. The job of a repeater is to receive the signal, regenerate it and rebroadcast it therefore extending the range of your wireless network. This would sit somewhere between your Access Point and your wireless client. Some repeaters, like the Range Expander series from LinkSys, don’t require it to be directly connected to the network via a cable. However, if security is an issue for you then be careful as some of these ignore certain security methods such as MAC address filtering. Also, some repeaters will only repeat wireless signals coming from its own product family, i.e.: if you have a D-Link Wireless Router you will have to get a D-Link repeater. The image below demonstrates the job of a repeater.

The Access Point transmits the signal. As it travels it decreases, until it hits the repeater and gets boosted. The newly transmitted signal is then received by an in-range wireless client.

Changing the Antenna

Changing the antenna of your access point can increase signal range and overall performance. Typical access points come with a 2dB or 4dB gain antenna but there are one’s available with 8, 14 and even 24dB. Antenna gain is measured in dBi (decibels-isotropic) which basically means how powerful the antenna is and how far it can provide a signal. Directional antennas are suitable for environments where you have a direct line of site from one access point to another and from access point to client; the signal travels in a straight line. Omni-Directional antennas distribute their signal in a circular 360 degrees motion over a horizontal pane, which is ideal for square areas.

Install Windows XP SP2

If you are using Windows XP on your wireless client - as I’m sure most of you are – installing Service Pack 2 would be a good idea. Check the Microsoft Website for download details. Windows XP Service Pack 2 comes with enhanced wireless support such as a new network setup wizard, built in support for WPA (Wi-Fi Protected Access), an updated Wireless Network Connection dialog box and amongst others, a rather nifty repair feature.

To utilize the repair feature all you have to do is right click the connection and select Repair or click the button on the support tab of the status dialog box. This will disable and then re-enable the connection (which clears many of the error conditions on wireless network adapters), clear the NetBT cache and flush the DNS cache. I often find that if my connection signal becomes low after a long period of activity, pressing the Repair button will boost it up to “Good” or “Very Good” depending on my location.

Network Settings

DHCP Addresses

DHCP configuration errors may also cause problems when connecting to a wireless network. Some of the newer access points on the market come with their own DHCP server which usually assigns addresses in the 192.168.0.x range. If your wired network uses a different range then you will probably find that wireless network clients are able to obtain an IP address and ping the access point but communication with other clients will not work. Your access point configuration interface should allow you to set which address scope to use. Set this to be the same as that of your other clients. You can also just disable the DHCP server on the access point and allow clients to obtain an address from the normal DHCP Server on your network.

Encryption Keys

Double check and re-enter your WEP/WPA encryption keys. Wireless Encryption will vary depending on which type of network you are connecting to. In Windows XP, on the Association tab of your wireless network properties dialog box, verify that your network key has been entered correctly and is valid for the network you are attempting to connect to.

MAC Address Filters

A great form of security to allow restricted access to your network. As I had explained in An Introduction to Wireless Networking Part 1, MAC Address Filters are a list of MAC addresses belonging to the clients that are allowed access to the network. This will only permit clients with the specified MAC Addresses to communicate with the network. Having said this, it may be the reason to your problem. Verify that the problematic client’s MAC is in the address list. If the network card had to be changed or a new device purchased recently, be sure to add it to the list.

Conclusion

After having read this article you should be familiar with common wireless network connections problems and what you can do to fix them. I hope that you will now be able to follow these steps when a wireless problem occurs and take the necessary action in solving such issues. Look out for Part 3 of my Introduction to wireless networking series in which I will take a closer look at security, give you some wireless network tips and tricks and also update you on the latest wireless networking news.

Wireless Security Filtering

Filtering

Managing access to a WLAN through WEP keys or authentication is one viable security measure. You can also configure access to be restricted according to device; to do this, you use the Media Access Control (MAC) address or Internet Protocol (IP) address. For example, you can employ filtering on your APs to keep out clients who do not have an authorized client adapter. Without an explicitly approved MAC address on the network adapter, it doesn't matter if the correct username and password are presented because the AP does not allow access.

Simply put, filtering checks a wireless client's MAC or IP address against a list of authorized MAC or IP addresses maintained on the AP. When a client tries to connect to the AP, it must be on the list. If it is not, the client cannot connect.

Filtering should not be the only security measure, however. Both MAC and IP addresses can be spoofed, thus circumventing this layer of security.

MAC Filtering

You can set up a MAC filter two ways:

• To pass traffic to and from all MAC addresses except those you specify.

• To block traffic to and from all MAC addresses except those you specify.

Furthermore, you can apply these filters to either or both the Ethernet and radio ports and to incoming or outgoing traffic.

Note

Be careful when setting MAC filters. If you incorrectly apply the setting, you can easily lock yourself out of the AP. If this does occur, use the command-line interface (CLI) to disable filters, and then go in and correct your mistake.

MAC filters are managed on the MAC Address Filters page ; simply follow these steps:

Step 1. On the AP's web page, click Services on the menu to the left of the page.

Step 2. Click Filters in the list of services.

Step 3. Click the Mac Address Filters tab on the Apply Filters page.

After you reach the Apply Filters page, you can enable MAC address filters.

Note

Be aware that software often changes. The version of the AP firmware you use might differ from what is shown here, but the steps are similar.

Setting MAC Filters

To configure a MAC filter, follow these steps:

Step 1. To create a new MAC address filter, click Create > Edit Filter Index > . To edit a filter, select the filter number from the menu.

Step 2. In the Filter Index field, identify the filter with a number between 700 and 799. This number is used to assign an access control list (ACL) for the filter.

Step 3. Enter a MAC address in the Add MAC Address field. The address is entered as three groups of four characters, separated by periods (for example, 0125.4275.7879).

Step 4. Use of the Mask entry field enables the filter to check against certain bits, but not others. For example, if you have several clients whose MAC addresses all end in the same four bits, you can use the mask to allow any clients whose MAC address matches those four bits. If you want to force an exact match of the MAC address, in the Mask entry field, enter FFFF.FFFF.FFFF. If you just want to check the last four bits, enter FFFF.FFFF.0000.

Step 5. Choose Action > Forward or choose Action > Block.

Step 6. Click Add. The MAC address you entered has been added to the Filters Classes field. You can remove this address by selecting it and clicking Delete Class.

Step 7. Choose Default Action > Forward All or Default Action > Block All. You must establish the default action for this filter, and it must be the opposite of the action for at least one of the MAC addresses in the filter. For example, if you chose Forward for several MAC addresses, you should select Block All as the filter's default action.

Step 8. Click Apply.

Step 9. Click the Apply Filters tab.

Step 10.Select the filter number from one of the MAC drop-down menus. The filter can be applied to either the Ethernet port, the radio ports, or both. You can also apply the filter to incoming traffic, outgoing traffic, or both.

Step 11. Click Apply.

Note

You need to restart the system, so that all clients are appropriately filtered.

IP Filtering

You can also limit access to your AP with IP filters. IP filtering can be applied based on IP address, IP protocol, and IP port. This allows or prevents the use of specific protocols through the AP's Ethernet and radio ports. Like MAC filtering, you can also set up the filter to allow or deny sending or receiving traffic from the AP based on IP address.You can set up IP filters to allow combinations of all three IP filtering components (address, protocol, and port).

IP filters are managed on the IP Filters page.

To reach the IP Filters page, follow these steps:
Step 1. On the AP's web page, click Services on the menu to the left of the page.

Step 2. Click Filters in the list of services.

Step 3. Click the IP Filters tab.

After you reach this page, you can enable IP filters.
Setting IP Filters

To configure an IP address filter, follow these steps:

Step 1. To create a new IP address filter, select Create > Edit Filter Index > . To edit a filter, select the filter number from the menu.

Step 2. In the Filter Name field, identify the filter with a name.

Step 3. Select Default Action > Forward All or Default Action > Block All from the Default Action. You must establish the default action for this filter and it must be the opposite of the action for at least one of the IP filters. For example, if you chose Forward for several IP addresses, you should select Block All as the filter's default action.

Step 4. To filter a specific IP address, enter that address under the IP Address section. The Destination Address field is used to filter traffic going to an address; the Source Address filters filter traffic coming from a given IP address.

Note

If you intend to block traffic to all IP addresses except those specified, make sure you include the IP address of your own computer in the list of specified exceptions; otherwise, your computer is shut out from the AP.

Step 5. The Mask entry field allows the filter to check against certain bits, but not others. Type the subnet mask in this field. The mask is used if you are filtering everything to or from a subnet.

Step 6. Select Action > Forward or select Action > Block.

Step 7. Click Add. The IP address you entered has been added to the Filters Classes field. This address can be removed if you select it and click Delete Class.

Step 8. To filter an IP protocol, select one of the protocols from the IP protocol drop-down menu, or select the Custom radio button and enter the number of an existing ACL in the Custom field. Enter an ACL number from 0 to 255.

Step 9. Select Action > Forward or select Action > Block.

Step 10. Click Add. The protocol appears in the Filters Classes field. This field is at the bottom of the page and is shown in Figure 8-4. This filter can be removed if you click Delete Class.

Step 11. To filter a TCP or UDP port protocol, select one of the common port protocols from the TCP Port or UDP Port drop-down menus, or you can select the Custom radio button and enter the number of an existing protocol in one of the Custom fields. Enter a protocol number from 0 to 65535.

Step 12. Select Action > Forward or select Action > Block.

Step 13. Click Add. The protocol appears in the Filters Classes field. This filter can be removed if you click Delete Class.

Step 14. Click Apply.

Step 15. Click the Apply Filters tab.

Step 16. Select the filter names from one of the IP drop-down menus. The filter can be applied to the Ethernet port, the radio ports, or both. You can also apply the filter to incoming traffic, outgoing traffic, or both.

Step 17. Click Apply.

WLAN extend - wireless range extension

On this page I will show you Methods for WLAN extend of radio coverage area. If you go farther away from access point, bandwidth and signal are lower and lower, until the point where there is no signal at all. The biggest impact on range of one access point has power of its transmitter.

Different WLAN standards signals have different ranges. You can compare them on what does wlan stand for

Interference could also influence on strength and range of signal. Other wireless networks or other sources of wireless signals can interference your WLAN network. This could cause decrease in radio coverage.

Obstacles like building, walls, especially steel reinforcing, or some natural obstacles even could cause complete loss of signal. Black spots are places where there is no signal at all.

BSS (Basic Service Set) is range of one access point. In many situations and applications radio coverage of one access point is not enough.

You could use following methods for extension of WLAN radio coverage:

1) Use access point in repeater mode - wireless distribution system.

2) Increase power level of access point.

3) Distribute access points optimally.

4) Use of secondary access point with non-overlapping channels.

5) WiFi signal booster

Setting up a wireless network or how to set up WiFi with the best security

Setting up a wireless network is not such an easy task. Check the best way for setting up home wireless network

How to set up WiFi ?

The best way is to start with finding your wireless router IP address. After that, connect to your wireless router IP address with your internet browser and start Setting up a wireless router.

Setting up wireless network ends up with Setting up Wireless card.

You need to know that parameters on wireless router and wireless cards have to match in order that the wireless card could connect to the router. This means, if you choose WPA with PSK as authentication on your wireless router, the same kind of authentication needs to be used on your wireless card. The pre-shared key also has to match. If you have MAC filtering applied on your wireless router, the MAC address of your wireless card needs to be added to the list.

All these things need to be taken care of, if you want to finish up with the successful wireless network setup.

Windows 7 Network Card Configuration

Let’s talk about Windows 7 network card (network adapter) configuration here, so that you could connect to Ethernet home network with wired connection. I would assume you have already configured network router correctly, and is ready to connect Windows 7 computer to this network by connecting computer’s network adapter to router’s LAN port with network cable.

Network Card Driver Installation

First you need to make sure you have installed Windows 7 network card driver. Without installing the driver, your network card will not work. If you plug in the network card the first time to the computer and boot up the Windows 7, the system will detect new hardware and prompt you to install the driver, you can then use the driver installation CD or the driver downloaded from vendor website to finish the installation. Sometimes Windows 7 will detect the card and install the driver automatically if it’s supported.

You need to check the driver status to make sure it works well after the driver installation, take a look on this network card driver status checking article if you are not sure how to do it.

TCP/IP Configuration

TCP/IP configuration in Windows 7 network card!! This is the most important part of network card configuration in Windows 7. You must configure the network card, so that this computer can communicate with other computers or network devices properly. You will need to have TCP/IP protocol and other Windows network items installed in order to make it work correctly.

This is how to configure it:

1) Go to Start and click on Control Panel.

2) Proceed to click View network status and tasks in Control Panel window.

3) Network and Sharing Center window will appear, then click Change adapter settings.

Note: Please note this widows will show Local Area Connection as access type if you have connected the computer to router with network cable.

4) Network Connections window will appear. Here you can right click on the network card that you wish to configure and click Properties.

5) In the Local Area Connection Properties, you need to have following items installed and enabled:

Client for Microsoft Networks – Allow your computer to access resources in a Microsoft network.

File and Printer Sharing for Microsoft Networks – Allow your computer to share files and printers in Microsoft network.

Internet Protocol Version 4 (TCP/IPv4) – The protocol that enables your computer to talk to other computers in your network. You need to specify IP address, netmask, gateway and other network information for it to work correctly. If you have configured DHCP setting on router, configure each computer to obtain IP address automatically. If you plan to assign IP address manually on each computer, assign the IP address by following your network design, and make sure the IP is unique. Having problem? You can take a look on this IP address and other network configuration in Windows 7 article.

Note: If you plan to use homegroup feature later, don’t disable the Internet Protocol Version 6 (TCP/IPv6) feature.

Link-Layer Topology Discovery Mapper I/O Driver and Link-Layer Topology Discovery Responder - Used to discover and display your home network map. Check this on how to enable Network Discovery in your network.

If you don’t have those specified items installed, click Install… and follow the instructions to install the items which you missed. Finally click OK to close the window.

At this moment, your Windows 7 computer should be connected to home network. Try to ping other computer or router IP, and access to Internet websites.

Network Location Type Setting

Once your computer is connected to home network, you are advised to set the Network Location, so appropriate firewall and security settings will be automatically set on computer.

If your computer is connected to home network, you should set the network location type as home network in Network and Sharing Center window.

Assigning Computer Name and Workgroup

Each computer in your network must be assigned a name and workgroup, so that it’s easy for your identification later. Follow step-by-step instructions here to set computer name and workgroup in Windows 7.

That’s all the Windows 7 network card configuration, after that you can proceed to do simple file sharing or password protected file sharing as you wish.

If you face network connectivity or website access problem, try to use ping tool to troubleshoot network problem.

Checking Network or Wireless Adapter Driver Status in Windows 7

You are advised to check network or wireless adapter driver status in Windows 7 after installing the driver in order to make sure it works well before trying to connect to wired or wireless network. I used to see users facing network connectivity problem due to incorrect or problematic driver problem, so don’t neglect this simple checking.

This is the way to check network or wireless adapter driver status:

1) Go to Start and click on Control Panel.

2) Control Panel window will appear, click Hardware and Sound.

Note: If you view Control Panel by Large Icons or Small Icons, you can just double click the Device Manager.

3) Click on Device Manager in Hardware and Sound window.

4) The Device Manager will appear, then locate and expand Network adapters and right click the network or wireless adapter you want to check, finally click on Properties.

5) The network or wireless adapter properties window will appear, your driver works well if it shows This device is working properly under General tab. You can also manually configure network adapter’s driver parameters under Advanced tab.

Note: If your device does not work well, click on Driver tab to check driver details, update driver, rollback driver, disable driver or uninstall driver.