Expression of Interest (EOI) for Provision of IP-MPLS based network for Unified communication Back-bone and VOIP based control communication system with associated LAN infrastructure at various stations of LJN, BSB, IZN Divisions and HQ Control Room over North Eastern Railway and TCP-IP based fire fighting System at Divisional Control Test Room, HQ Control Room. Provision of FXS media Gateways with associated LAN, OFC infrastructure for existing SIP Based IP Exchange in HQ Gorakhpur for Customer of RailTel