Having Irish permanent residency allows you to remain in Ireland for more than 90 days. To get residency, you must obtain an Ireland Residency Permit or IRP certificate of registration.
Edmissions
Foreign nationals must live in Ireland for at least five consecutive years to qualify for permanent residency.
You need to send your application through the mail to the Long-Term Residency Division of the Irish Naturalisation and Immigration Service, INIS along with supporting documents.