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Continue to ChatHLR and MSC Powerful Backbone for SMSC https://vinodsblog.com/2011/10/01/hlr-and-msc-powerful-backbone-for-smsc/
HLR and MSC Powerful Backbone for SMSC https://vinodsblog.com/2011/10/01/hlr-and-msc-powerful-backbone-for-smsc/