A Wildcard SSL Certificates helps in achieving SSL encryption on multiple sub-domains with the help of a single certificate as long as the sub domains are on one same physical server, share the same second-level domain name and are under the control of a single organization.
For example, one wildcard certificate *.yourdomain.com would be able to secure the following websites :
- www.yourdomain.com
- secure.yourdomain.com
- product.yourdomain.com
- info.yourdomain.com
- download.yourdomain.com
- anything.yourdomain.com
However, the following will not work:
- foo.info.yourdomain.com
- bar.secure.yourdomain.com
These sites would require a separate certificate for each sub-domain:
- *.info.yourdomain.com
- *.secure.yourdomain.com
Older Browsers#
'Older' browsers don't recognize wildcard certificates and report a name conflict between the domain and the certificate.- IE5.5 is ok,
- and I think IE5.0sp2 is ok.
- Prior versions of IE will have problems and I'm not sure
- Netscape - 7 onwards is definitely ok, and I think 6 is as well.
- Not sure about 4.7.
