I wanted to know whether paying 'fitrana' (zakah al-fitr) compulsory?
Muslims are obliged to pay zakah al-fitr on day of Eid al-Fitr. In this connection Mr Ghamidi writes in Meezaan:
Sadaqah al-Fitr (religious obligation to offer charity in a fixed amount) is also a form of Zakah. Regardless of age and sex distinction, all members of a Muslim family are obliged to give away the fixed amount that is equivalent of two times meal for a man. The duty is discharged at the end of the month of the Ramadan but before the Eid congregation on the first of Shawwaal. Ibne Abbas (rta) explained that the duty has been enjoined upon the Muslims to cancel the bad affects of all kind of idle talk and sexual desires on the part of the worshippers during the sacred month. It is also a means to help the poor get their provisions for the Eid Day. (Abu Daud, No:1609)
During the Prophet's lifetime this obligation was commonly paid in kind therefore, he carefully assessed and fixed 2.5 Kg. of the grain etc given.
فرض رسول الله صلى الله عليه و سلم زكاة الفطر صاعا من تمر أو صاعا من شعير على العبد والحر والذكر والأنثى والصغير والكبير من المسلمين وأمر بها أن تؤدى قبل خروج الناس إلى الصلاة
The Messenger of God has enjoined the payment of Sadaqah al-Fitr on every Muslim. A Saa' (ie 25 kg.) of dates or a Saa' of barley has to be paid by every individual slave or free, male or female, young or old. He has ordered that it be paid before setting off for the prayer. (Bukhari: 1503)
(Ghamidi, Meezaan, (Translated by Mr Shehzad Saleem)