2021. Proposing a Secure URL Shortening Service by using Blackboard Architecture. Journal of Al-Rafidain University College For Sciences ( Print ISSN: 1681-6870 ,Online ISSN: 2790-2293 ). 34, 2 (Oct. 2021), 209–226. DOI:https://doi.org/10.55562/jrucs.v34i2.291.