CCNP: Building Cisco Multilayer Switched Networks Study Guide (642-811)

The Universal Asynchronous Receiver/Transmitter: A chip that governs asynchronous communications. Its primary function is to buffer incoming data, but it also buffers outbound bits.

User Datagram Protocol: A connectionless Transport layer protocol in the TCP/IP protocol stack that simply enables datagrams to be exchanged without acknowledgements or delivery guarantees, requiring other protocols to handle error processing and retransmission. UDP is defined in RFC 768.

Reference point between a TE1 and an ISDN network. The U reference point understands ISDN signaling techniques and uses a two-wire connection.

Used for direct host-to-host communication. Communication is directed to only one destination and is originated from only one source.

A method of shared tree multicast forwarding. This method allows only multicast data to be forwarded from the RP.

A host is uniquely identified by the MAC address, because this address is not repeated on any other host anywhere.

HDLC frames used for control-management purposes, such as link startup and shutdown or mode specification.

Enables a switch to immediately begin forwarding frames on blocked ports when a failure is detected on the root port.

Routers nearer to the transmitting multicast server are said to be upstream from the receiving client.

unshielded twisted-pair: Copper wiring used in small-to-large networks to connect host devices to hubs and switches. Also used to connect switch to switch or hub to hub.