JavaCard OS

Hi all.

We have just finished an applet and the CAP file size is approximately 120K. Now we are trying to choose the appropriate java card candidate. If fact, we would like to use java card with USB form, like eJava Token. But it's NVM 110k is smaller than 120K. So would anyone recommend other appropriate candidates to me?

Many thanks.

A22CR card has 146K NVM. You can try to use this card.

Thanks for your reply. But we want the java card with USB reader form,just like eJava Token.

If that is the case, it seems that there are little java card with USB reader form in the market.

But here is a method. You can have a try. In fact, Debug.cap component file in the CAP file will not be downloaded into card when downloading the whole CAP file into card. And usually Debug.cap occupies large memory. So just check Debug.cap component size of your CAP file and your CAP file size is far smaller than 120K.

Tip:
Use JCIDE and pyApdutool to do some test first. JCIDE has virtual simulator of eJava Token. Enable this simulator and download your applet into this simulator via pyApdutool.

Another thing to point out is to review through your JavaCard applet again to look for areas to optimize with as little compromise to security as possible. Most applet codes are very bulky due to lack of optimization and recently, I have been working on a commercial applet which seems to not fit into a USB JavaCard token (Feitian's K9 token using 80 KB EEPROM NVM with NXP J3E081). I hit above the 80 KB limit on many occasions and everytime I review my codes, I am sure to be able to find ways to optimize it even better and reduce it to 70+ KB despite having a ton of features in it.

Another way is to get A22CR cards and cut them to SIM sizes and use the USB SIM reader.

tay00000 wrote:Another way is to get A22CR cards and cut them to SIM sizes and use the USB SIM reader.

This is a good idea.

mabel wrote:If that is the case, it seems that there are little java card with USB reader form in the market.

But here is a method. You can have a try. In fact, Debug.cap component file in the CAP file will not be downloaded into card when downloading the whole CAP file into card. And usually Debug.cap occupies large memory. So just check Debug.cap component size of your CAP file and your CAP file size is far smaller than 120K.

Tip:
Use JCIDE and pyApdutool to do some test first. JCIDE has virtual simulator of eJava Token. Enable this simulator and download your applet into this simulator via pyApdutool.

Thank you very much for your answer. Your answer certainly helps.

tay00000 wrote:Another thing to point out is to review through your JavaCard applet again to look for areas to optimize with as little compromise to security as possible. Most applet codes are very bulky due to lack of optimization and recently, I have been working on a commercial applet which seems to not fit into a USB JavaCard token (Feitian's K9 token using 80 KB EEPROM NVM with NXP J3E081). I hit above the 80 KB limit on many occasions and everytime I review my codes, I am sure to be able to find ways to optimize it even better and reduce it to 70+ KB despite having a ton of features in it.

Another way is to get A22CR cards and cut them to SIM sizes and use the USB SIM reader.

Thank you so much for your suggestion. Using A22CR cards with SIM sizes and use the USB SIM reader is a good alternation solution.