This is used to describe a traditional, analog telephone circuit for a residence or business. A fiber optic transmission system for high-speed digital traffic. It uses a self-healing ring architecture that is able to reroute traffic if a line goes down. Spur A branch of a communications network, which connects a site to a communications backbone network, without path diversity. Same as a Lateral.
Traffic is a very general term and can refer to transactions and messages of any kind.
Vault An enclosure used to terminate duct. Usually underground, such as a manhole or handhole. WAN Wide Area Network. A communications network that covers a wide geographic area or interconnects two or more Local Area Networks.