A wide area network (WAN) is a telecommunications network that extends over a large geographic area. Wide area networks are often established with leased telecommunication circuits.[1] Read more about WANs on Wikipedia
SONET
Synchronous Optical Networking (SONET) and Synchronous Digital Hierarchy (SDH) are standardized protocols that transfer multiple digital bit streams synchronously over optical fiber using lasers or highly coherent light from light-emitting diodes (LEDs). At low transmission rates data can also be transferred via an electrical interface. The method was developed to replace the plesiochronous digital hierarchy (PDH) system for transporting large amounts of telephone calls and data traffic over the same fiber without the problems of synchronization. Read more about SONET on Wikipedia
MPLS
Multiprotocol Label Switching (MPLS) is a routing technique in telecommunications networks that directs data from one node to the next based on labels rather than network addresses.[1] Whereas network addresses identify endpoints, the labels identify established paths between endpoints. MPLS can encapsulate packets of various network protocols, hence the multiprotocol component of the name. MPLS supports a range of access technologies, including T1/E1, ATM, Frame Relay, and DSL. Read more about MPLS on Wikipedia
SD-WAN
A software-defined wide area network (SD-WAN) is a wide area network that uses software-defined networking technology, such as communicating over the Internet using overlay tunnels which are encrypted when destined for internal organization locations.[1] Read more about SD-WAN on Wikipedia
CGNAT
Carrier-grade NAT (CGN or CGNAT), also known as large-scale NAT (LSN), is a type of network address translation (NAT) used by ISPs in IPv4 network design. With CGNAT, end sites, in particular residential networks, are configured with private network addresses that are translated to public IPv4 addresses by middlebox network address translator devices embedded in the network operator’s network, permitting the sharing of small pools of public addresses among many end users. This essentially repeats the traditional customer-premise NAT function at the ISP level. Read more about CGNAT on Wikipedia