Packet Switching / WAN Technology

X.25: defines communication between DTE and DCE devices.
Switched multimegabit data services (SMDS):
- Is a connectionless protocol and can provide bandwidth for exchange of large amounts of data.
- A connectionless, high-speed, datagram-based WAN technology for communication over public data networks.
Frame Relay: Forwards packets to their destinations and doesn’t unpack frames at each node.
Link access procedure balanced (LAPB): Ensures that frames are conrrectly sequenced and error free.
Asynchronous transfer mode (ATM):
- transmits data in fixed size cells of 53 byte and can provide bandwidth on demand.
- Connection oriented switching technology that uses a cell-switching method.

Synchronous data link control (SDLC): bit oriented synchronous protocol.
High level data link control (HDLC): A bit oriented data link protocol.
Switching: A virtual connection which acts like a dedicated link between the sender and the receiver devices.

Password authentication protocol (PAP): uses an authentication server to compare supplied credentials against stored credentials.
Challenge handshake authentication protocol (CHAP): enables user auth without revealing a shared password between two entities.
Extensible Authentication Protocol (EAP): works directly at the data link layer.
Point-to-point protocol (PPP): Supports asynchronous and synchronous connections and network protocol multiplexing.
Serial Line Internet Protocol (SLIP): Frames datagrams for transmission but doesn’t provide error detection or data compression.