Section 625-2-4 - NETWORK TRUNKING AND CONNECTIVITY REQUIREMENTSA.General Network Requirements for the SP and LECs1. The 9-1-1 trunks on the E9-1-1 network shall be dedicated facilities that are not shared with any other telecommunications traffic, i.e., trunks carrying 9-1-1 traffic between the Central Office and the E9-1-1 tandems.2. All telephone circuits or equipment used exclusively for 9-1-1, or essential to the operation of the E9-1-1 system, shall be clearly identified (beginning with the trunks from the Central Office to the Selective Router) to insure proper handling. This requirement applies to equipment accessible as of the effective date of the rule and any equipment installed or repaired after the effective date of the rule.3. Any entity connecting to the Maine E9-1-1 network shall ensure that the 9-1-1 trunks will have interoffice, loop and carrier system diversity when such diversity can be achieved using existing facilities. Trunks shall be divided as equally as possible across available carrier systems.B.Requirements of LECs1.Connecting to the E9-1-1 Networka.Trunks. Each LEC shall provide a minimum of two redundant trunks using SS7 to each of the two selective routers (tandems). The number of incoming E9-1-1 trunk lines to each selective router shall be based upon a grade of service of P.01. Diverse routes should be used when possible within the existing network.b.Certification and Compliance. Each LEC shall certify annually to the Bureau that it meets the P.01 grade of service. If P.01 grade of service is not being met, the Bureau may request the LEC to conduct a traffic study. The Bureau, in cooperation with the SP and LEC, will determine the required trunking increases to meet the P.01 grade of service. The LEC shall implement any trunking increases within 60 days.65- 625 C.M.R. ch. 2, § 4