There are 2 possible areas raised by this question. The first is a security patch needed to fix the firmware of your router, which by the way is not dwl-952. Your router is a di 954. Dwl 952 is a bundled router and network interface. The details of the firmware update are below.
Security patch for your D-Link router
These firmware updates address the security vulnerabilities in affected D-Link routers. D-Link will update this continually and we strongly recommend all users to install the relevant updates.
As there are different hardware revisions on our products, please check this on your device before downloading the correct corresponding firmware update. The hardware revision information can usually be found on the product label on the underside of the product next to the serial number. Alternatively, they can also be found on the device web configuration.
Please make sure you follow the firmware install guide provided within the ZIP firmware package.
DI-524 Revision E1/E3Thu, 28/11/13
The new firmware 5.13b01 that fixes the security vulnerabilities
DI-524 Revision Ex 5.13b01
Please note: please unzip the file and use the file DI524Ex_FW513B01.bin to update firmware.
DI-524UP Revision A1/A2Thu, 28/11/13
The new firmware 1.08b02 that fixes the security vulnerabilities
DI-524UP Revision Ax 1.08b02
Please note: please unzip the file and use the file DI524UPAx_FW108B02.bix to update firmware.
The second possibility is to set the local security on your network.
From the wikipedia page:
is the prevention of unauthorized access or damage to computers using wireless
networks. The most common types of wireless security are Wired Equivalent Privacy
(WEP) and Wi-Fi Protected Access
(WPA). WEP is a notoriously weak security standard. The password it uses can often be cracked in a few minutes with a basic laptop computer and widely available software tools. WEP is an old IEEE 802.11 standard from 1999 which was outdated in 2003 by WPA or Wi-Fi Protected Access. WPA was a quick alternative to improve security over WEP. The current standard is WPA2; some hardware cannot support WPA2 without firmware upgrade or replacement. WPA2 uses an encryption device which encrypts the network with a 256 bit key; the longer key length improves security over WEP.
The complete article is here
Log in to your router and find the wireless security section. Set up the security model that best suits your needs and then set up your wireless network card with the same information.