What would a broadband column be without some jargon?
FTP
File Transfer Protocol provides facilities for bidirectional transfers between remote computer systems. FTP is a basic, no-nonsense method for moving entire files around the Net. Several ftp “clients,” as applications that perform this duty are called, provide the valuable ability to pick up a transfer where it left off if the connection fails, a common problem with dial-up service.
DWDM
Dense Wave Division Multiplexing is the frequency domain equivalent of time-domain multiplexing. DWDM is used by telcos to launch multiple data streams down a fiber, each carried on its own wavelength (or frequency or color, all the same thing) of coherent laser light. This allows one fiber to carry simultaneously many more streams of data than it was originally designed to carry, saving upgrade costs.
CIRCUIT SWITCHED
The Old Way. Think Ernestine the operator, patch cord in hand. Switched circuits mean that, at setup time, a connection is made between two parties to complete a “call.” When the call is finished, the entire connection structure is broken down to be rebuilt for the next call, a slow and inefficient process.
PACKET SWITCHED
The New Way. All nodes on the network are “always on,” and able to send, receive and forward “packets” of data, small quanta of information framed or “wrapped” in a virtual envelope with address and routing instructions “printed” on the outside.
POTS
Plain Ol’ Telephone Service, that reliable product we all take for granted.
PSTN
Public Switched Telephone Network, which carries our POTS around the world.
QOS
Quality of Service is a generic network mechanism that provides some combination of guaranteed throughput, error rate and latency. The current PSTN uses RSVP protocols as a QoS Band-Aid.
SYMMETRICAL BROADBAND
Same speed/bandwidth in both directions, the “S” in SDSL. The less costly ADSL service is asymmetrical, with download speeds far greater than upload speeds.
VOIP
Voice over IP means simply that “telephone” voice traffic is encapsulated within IP packets rather than over traditional switched circuits, with great potential cost savings all around.
VPN
Virtual Private Networks provide virtual secure connections over an unsecure public network.
WAP
Wireless Application Protocol is a spec-defining, secure, bi-directional Net access via wireless devices, specifically those without keyboards. WAP is not an international standard and will most likely go the way of the dinosaur real soon.
