Hi Muhammad,
I am in Time & Attendance field since last 9 years, working in Design & Development Engineer.
According to my experience, there is no need to have smartcards for time & attendance.
If you want to use it as a Latest technology, then it is another matter. In that case you can use the IIC Memory cards or the Sync. Memory cards. simple because of low cost compared to the different types of smart cards. Even then it will be costly compared to the current technologies used in Time & Attendance such as Barcodes, Magnetic cards, Proximity cards...etc.
You can use other types of SmartCards also, but will be simply overkill.
There are many different type of cards: IIC Memory cards, Synchronous memory cards, CPU Cards.
If you are looking at security point of view on simple memory cards, then by software you can achieve an excellent level of security by software just needed by time and attendance field.
And implementing them is a very very time consuming process typically on 8051 based products. But you can develop on 8051, you will get a lot of help on this forum if you specifically ask for it.

Hope this answers your question.

To the Forum members:
Time And Attendance is different than PAYROLL.
Time and Attendance just gives you the number of working hours, number of worked days,..etc...etc. Which is given to the payroll software. There are a lot many things that need to be done by Attendance software, rather than the instrument which collects the IN-OUT timings of employees.. I would it is just 10% of the full Attendance System (other than Payroll).


Hope it clears the doubts of Time & Attendance System.

Mr. Kiran V. Sutar.