A Leased line is a dedicated communication channel that interconnects two or more sites. This is a service contract between a customer and a provider. Leased lines are used for Internet, data and even telephone services. They are typically run on fiber optic cables to provide large bandwidth and speed. A Multiprotocol Label Switching (MPLS) is a routing technique in telecommunications networks that directs data from one node to the next based on short path labels rather than long network addresses, thus avoiding complex lookups in a routing table and speeding traffic flows. A Session Initiation Protocol (SIP) trunking is a service offered by a communications service provider that uses the protocol to provision voice over IP (VoIP) connectivity between an on-premises phone system and the public switched telephone network (PSTN). SIP is used for call establishment, management and teardown. A National Long Distance (NLD) service refers to the carriage of switched-bearer telecommunications services over a long distance network i.e., a network connecting different short distance charging areas (SDCAs).