It is believed that increased computing power will make the commonly used 1024-bit keys possible to break by 2011. There is a side effect in switching to the larger keys that some old web browsers don’t support > 1024 bit keys. I can’t find a good reference that tells me which versions of which browsers, but this is something to keep in mind.
We’ve rebuilt the NowSMS SSL library to generate 2048 bit keys when generating a new certificate signing request (CSR). An update can be downloaded at
http://www.nowsms.com/download/smsssl.zip.To install the update, stop the NowSMS services and exit NowSMS.
Unfortunately, the change to 2048 bit key requirements will cause problems for renewals for customers that already have an SSL certificate signed by a certificate authority (CA).
When your renewal time comes up, many CAs will not renew your certificate until you switch to a 2048 bit key.
However, if you generate a new server certificate request with NowSMS, this forces the existing certificate to be immediately invalidated, which may cause problems for existing clients during the certificate renewal process.
(This problem is not specific to NowSMS … many web server administrators are facing similar problems.)If you face this renewal issue with NowSMS, follow this procedure:
- Locate and backup the following NowSMS files (in either Program Files\NowSMS for Windows XP/2003 or ProgramData\NowSMS for Windows Vista/7/2008):
SSL.CRT
SSL.CSR
SSL.CA
SSL.INI
SSL.KEY - On the “SSL/TLS” page of NowSMS, select the option to “Generate Server Certificate”.
- You will be warned that doing this will invalidate your existing certificate. If you have backed up the files that I mentioned above, select “Yes” to continue.
- After the new certificate signing request has been generated, copy the new versions of SSL.CRT, SSL.CSR, SSL.INI and SSL.KEY to a different location for backup. (Note: There will not be an SSL.CA file as this file will not exist until you get your signed certificate back from the CA.)
- Put the old backup copies of these files, including SSL.CA, back in the appropriate NowSMS directory.
- Use the new SSL.CSR to request a signed certificate from your CA. When you get the signed certificate back from the CA, save it as SSL.CA.
- Copy the new version of these files, including SSL.CA to the appropriate NowSMS directory and restart the NowSMS services.
Related pages:
- NowSMS and SSL Certificate Chains If you have purchased an SSL certificate from a certificate authority for use on a NowSMS server, you may encounter...
- Existing Customer: Moving NowSMS to a new Computer If you need to move NowSMS to a new computer, this will require a new Activation Code. You can easily...
- NowWAP Statistics Reports The log files created by NowWAP are of a text format that follows the common log format for web servers....
- Migrating to a Multiple Server MMSC, WAP Gateway, or NowSMS Gateway The recent postings about multiple server redundant NowSMS or NowWAP configurations have generated a lot of questions from existing customers...
- New Customer: Installing a Purchased License Version When you purchase a NowSMS license, you will not be able to apply this license to the software until you...
- NowSMS in Fault Tolerant or Redundant Load Balanced Environment For many configurations it is desirable to install NowSMS on multiple servers in order to achieve fault tolerance and/or improved...
- High Availability Environments For many configurations it is desirable to install NowSMS on multiple servers in order to achieve fault tolerance and/or improved...
- Receiving MMS Messages with a PHP Script: HTTP File Upload Post Note: The PHP script referenced in this section can be downloaded at the following link: http://www.nowsms.com/download/php2waymms.zip NowSMS is a popular...
- Repairing a Corrupt MMSC User Database We recently had a customer whose MMSC stopped automatically provisioning new users. The MMSC user database had become corrupt, preventing...
- More Thoughts on the NowSMS Security Issue An additional thought … if you are concerned about the potential security issues described in the previous blog entry, but...
Topic Category: SSL/TLS
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Note: The SSL update has been rolled into the lastest NowSMS update. For more information, please see http://blog.nowsms.com/2010/05/nowsms-update-interim-release-20100507.html