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Hack50.Fix Windows Wireless

Hack 50. Fix Windows Wireless

Windows Wireless is largely self-configuring and mostly problem free. But Windows can sometimes shoot itself in the foot , and so it is sometimes with its Wireless Zero Configuration Service .

Works with: Windows version of Skype.

The Windows Wireless Zero Configuration Service (WZCS) is meant to help you, by doing all of the wireless configuration on your behalf . But it can become as much of a hindrance as a help as far as Skype is concerned .

During operation, the WZCS constantly hunts around for a better WiFi connection, and if it finds one, it switches you to that connection and away from your current connection. However, this switch is not instantaneous. This is not a problem if you are, say, browsing the Internet, as the momentary disruption to your Internet connection is not noticeable. However, Skype is sensitive to both latency and packet loss, both of which are adversely affected during the switch. if you are in a WiFi " noisy " location, the WZCS might constantly try to switch your machine from one access point to another, and possibly back again. Even the WZCS's habit of continuously hunting around for a better wireless connection by hopping from access point to access point can degrade call quality, as latency is injected into your connection and packets are lost.

Fortunately, the WZCS, which is switched on by default in Windows, can be disabled, but only after Windows startup; otherwise , your wireless services will fail to start. After Windows startup, you can stop the WZCS by selecting Start Control Panel Administrative Tools Services, right-clicking on Wireless Zero Configuration, and choosing Stop.

Alternatively, if you don't want to have to remember this sequence of actions every time you start Windows, you can add the following entry to the Windows registry using RegEdit (select Start Run…, enter "RegEdit," and click OK) to do the job for you:

HKEY_CURRENT_USER
	  Software

	    Microsoft 
	       Windows 
	          Current Version 
	             Run 
	               WZCS-Killer REG_SZ "c:\windows\system32\net.exe" stop WZCSVC

4.9.1. See Also

If you have a wireless or nonwireless router that is causing problems, you might want to look at "Fix Badly Behaving Routers" [Hack #51] .

Hack 51. Fix Badly Behaving Routers

Skype works without a problem with most routers, both wireless and nonwireless. This hack is for those of you who have a router that behaves badly with Skype, or vice versa !

Works with: all versions of Skype.

If Skype habitually drops calls, suffers from poor call quality, or simply doesn't work at all, after testing all else you should turn your attention to your network router. By working your way through this list of things to try, you stand a good chance of either fixing the problem or resigning yourself to buying a new router!

Reset your router: If problems have started to occur only recently and prior to that, your Skype calls were largely trouble free try resetting your router. You can do this by either pressing the Reset button (most routers have one, though it's oftentimes tucked away so that the router is not easily reset by accident ), or powering the router off and then on again.
US Robotics router: Go to the configuration settings, and under Access/Special App, look for a setting named PC-to-Phone. Enable it.
Other routers: Look for a setting similar to that for the US Robotics router and enable it.
Avoid being a super node: Skype uses a lot of simultaneous port connections. When you become a super node, the number of connections can increase substantially. This might overwhelm your router, especially if it has very limited built-in processing power. If you stop Skype from using ports 80 and 443 for incoming connections (select Skype Tools Options… Connection on Windows or Skype Tools Options… Advanced on Linux; this option is not available on Mac OS X or Pocket PC), you will very likely not become a super node. However, I must say that Skype is continuously being developed, and the rules by which a regular Skype node (client) becomes a super node are not public, so you can never be sure your node is not operating as a super node.
Enable ports 80 and 443: Letting Skype use ports 80 and 443 for incoming connections can improve things, as it gives Skype more options and flexibility in terms of routing traffic. However, doing so does increase the probability that you may become a super node, which can create problems of its own (as discussed earlier). At first glance, this suggestion may seem to contradict the advice I gave earlier under the "Avoid being a super node" heading, which argues in favor of closing off ports 80 and 443. The point is that both enabling and disabling ports 80 and 443 has advantages and disadvantages, in both cases. I suggest you try both approaches to see which brings the greatest net benefit.
Port scanning: Routers sometimes block Skype because it uses a large number of ports (TCP and UDP). Some malware programs go from port to port, in a process call port scanning, probing each to find a vulnerability to exploit. Because Skype tries to use so many ports, it can be mistaken for port-scanning malware and therefore be blocked. If your router blocks this type of behavior, disable its port-scanning blocking feature. However, bear in mind that doing so might make you more vulnerable to port-scanning malware.
Port forwarding: You can find out the port number, let's call it N, that Skype prefers to use for incoming connections, under connection options (select Skype Tools Options… Connection on Windows, Tools Options… Advanced on Linux, or Skype Preferences… Advanced on Mac OS X; this option is not available for Pocket PC). If your machine lives behind a restrictive NAT or firewall, it might not be accessible to other machines outside on the Internet, so Skype wont work. However, by using port forwarding, incoming connection requests to port N (and/or ports 80 and 443) can be forwarded directly to your machine, allowing machines on the Internet to connect with your machine and, in so doing, enabling Skype to work. You can find an excellent resource for support documents specifically on port forwarding for individual router models at http://www.portforward.com/routers.htm. You can find a more general tutorial on port forwarding at http://www.dlink.com.au/tech/drivers/files/modems/DSL-302G_Open.ports_DMZ.zip. Although this tutorial is specific to a D-Link router, it nevertheless has information useful to anyone considering opening ports for forwarding.
Erratic or strange router behavior: For unknown reasons, some routers (wireless and nonwireless) behave erratically with Skype. Common router models reported to have this problem are the D-Link 604 (nonwireless), D-Link 614 (wireless), Linksys BEFSR41 (nonwireless), and Linksys BEFSX41 (nonwireless). There are others. If upgrading your router firmware doesn't fix the problem, there's very little you can do, other than buy a new router!
Upgrade firmware: This is always worth a try and it costs you nothing. By upgrading to the latest firmware for your router (visit the manufacturer's web site), you might not only cure all sorts of problems, but also boost your router's performance.
Buy a new router: This is always a last resort, but it's worth considering if all else has failed and you're fairly sure that the problem is with your router.

4.10.1. See Also

It might also be worth testing your Internet connection for Skype friendliness (see "Test Your Connection for Skype Friendliness" [Hack #38] ).
You can get a handle on jitter, packet loss, and other things influenced by your router's behavior by looking at the technical details of the calls you make (see "Display the Technical Details of a Call" [Hack #47] ).