Sri Lanka Identification Number (SLIN)

This is a discussion note prepared based on the proceedings of the Operational Committee of the Personal Domain of LIFe and the discussions held with the technical team of Registration of Persons Department (RPD) which was led by CG, RPD.

Current National Identity Card Number (NICN)

Sri Lanka's current National Identity Card number is of the below format.

Length of the number is 10. “Birthday of the year & gender” (ddd) field is used to identify the gender where 500 is added to “birth day of the year” to reflect that the card holder is female.

When this number is used in information systems the following key limitations make the NIC Number unusable.

1. This number format can not be used as an unique number in information systems where the information on personal records of citizens who are born in different centuries should be captured as the century of the birth year cannot be denoted by the two digit “Birth Year” field. (e.g. Population Registry, Land Registry, National Archives, etc)
2. If the number of birth registrations exceeds 999 per gender per day the system can not accommodate NIC numbers for such births.

NIC Number Proposed in LIFe V2

In LIFe V2 a new NIC format was proposed trying to address these issues to a certain extend.

Length of the number is 10. One digit long “Birth Century” field has been introduced to denote the the century of the birth year. This has been encoded as 0 - 20th Century, 1 - 21st Century, etc. “Birth Century” field is also used to handle the overflow from “nnn” where the Y value is greater than 4 it represents an overflow for the corresponding century (e.g. 5 - overflow from 20th Century, 6 - overflow from 21st Century etc.).

This number format also has a critical limitations which makes it unusable in some of the information systems. The “Birth Century” only starts from 20th Century. Therefore the information about people who were born before the 20th Century cannot be captured by this version of NIC number. Systems affected due to this drawback are Population Registry, Land Registry, National Archives, etc.

Proposed Sri Lanka Identification Number (SLIN)

The following two options have emerged as solutions to overcome the limitations mentioned above. However one option has to be selected as the unique number to be used as the Identification Number of individuals in information systems.

It should be noted that this number will in the future be usually issued during the birth registration process by the Register General's Department (RGD). RGD has already developed a system (which is now being tested) for registering births and issuing the SLIN.

Considering the current global trends, it is also proposed that the registration number to be renamed as Sri Lanka Identification Number (SLIN). If SLIN would be used by RPD as-it-is it could be referred to as SLIN by RPD. If RPD would need to add more information to SLIN and\or amend SLIN for persons registration purposes (as mentioned below), RPD could use another name for that number such as National Identity Card Number (NICN).

Option 1 (This option was recommended by the Operations Committee of Personal Domain of LIFe)

(a) Represent the Birth Year in four digits in the SLIN to make it possible to capture the information related to births which have occurred even before 20th century

(b) Increase the number of digits in the serial number to four to enable capturing of more than 999 births per day per gender

Length of the number is 13.

It should be noted that the the trailing alpha character will not be a part of the SLIN (length = 12) which will originally be issued by RGD. The alpha character will be added and changed by RPD as and when necessary. (In this instance RPD will need to use another name for the number; i.e. NICN of which length will be 13)

Only drawback of the proposed number format is that it does not facilitate a smooth transition from old number to the new number for the existing identity cards as the lengths of proposed and existing serial numbers are different. However, if a re-registration process of the entire population is to take place for issuing new identity cards, this constraint would not arise.

RGD should issue the SLIN comprising first 12 numbers and RPD will form time to time change the final character depending on the ID card version. 

Option 2

The second option proposes an approach which provides a smoother transition from the current identity card numbers to SLIN.

(a) Represent the Birth Year in four digits in the SLIN to make it possible to capture the information related to births which have occurred before 20th century (same as 1 (a))

(b) Here the overflow is to be handled by using a different character in alpha character field which would signify that the serial number is a result of an overflow. (This character can be used to denote any other concept such as card version.)

 Length of the number is 12.

Since the serial number of existing cards is 3 digits long the current identity card holders just need to add the first two digits of their birth year in front of the current NIC number to derive the SLIN. One drawback of this number format is that it makes the number generation logic slightly complicated since overflows need to be handled using the alpha character field which is not currently generated through running the algorithm.

In case this format is agreed upon it should be decided by the Operational Committee of Personal Domain of LIFe as such how the alpha character would be used to denote the overflow and the different card versions. This is critically important as RGD would generate the SLIN for future citizens hence this should be defined to handle “over flow + version” combination. (The Operational Committee is scheduled to meet soon t take up this issue).

Another implication of this format is the possible inconsistency of the SLIN. For example RDG could generate a SLIN for a citizen which would have an alpha character to denote the overflow. If that alpha character would subsequently be replaced (even several times) by RPD to denote different versions of the card, there could be more than one SLINs stored at any given time in different information systems for the same person. Therefore in this format, the SLIN could become a dynamic number which could be in conflict with identification/authentication fundamentals and even could jeopardize some of the identification methodologies employed.

Sanjaya Karunasena
Chief Technology Officer
Information and Communication Technology Agency of Sri Lanka

Wasantha Deshapriya
Director
Re-engineering Government Programme
Information and Communication Technology Agency of Sri Lanka