If a South Asian convention against light arms and ammunition has to be meaningful it must compel the state parties to act against non-state actors at the behest of other state parties. In the absence of such a convention, India might submit the list of training facilities on the other side of LOC to Pakistan and the latter can simply discuss them. The convention should particularly focus on ammunitions and explosives. Since light weapons are small by definition, they tend to be easy to smuggle and difficult to detect. On the other hand, ammunition and explosives tend to be heavy and easier to detect.
Weapons are useless without ammunition.
Therefore, an emphasis on ammunition can solve half the problem. It would be also necessary to complement the regional convention with the establishment of national commissions. Light weapons per se can not be banned. They have a legitimate use by the security forces. It is therefore necessary to distinguish between legal and illegal weapons so that action can be engineered against the latter.