Group: digital communication

topic root > Group: computer science

computer science
distributed systems
electronic mail
parallel processing
a single system image
communicating sequential processes
computer architecture
document-centered system
electronic meetings
interprocess communication
open systems
Petri net
reliability of distributed systems
remote procedure call
routing electronic mailing
translation of data
security leaks and weaknesses
synchronous communication through a channel

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Traditional communication was analog -- sound waves, light waves, electrical waves, and radio waves. Now, communication is increasingly digital. Physical inputs such as sound waves are converted to numbers, these numbers are transmitted over the internet, and reconstructed as sound waves and images. Computers communicate without translation to and from an analog medium.

Communication and computation are complementary. The results of computation at one place are needed at other places, whether within a computer chip or across the internet. Communication must be reliable from end-to-end. The costs of communication are substantial in both time and material. (cbb 8/06)

Group members up

Topic: broadcasting information
Topic: channel multiplexing
Topic: communication port
Topic: communication protocols
Topic: hardware for interprocess communication
Topic: IEEE488 instrument bus
Topic: Internet
Topic: message queues for communication
Topic: reliable broadcast
Topic: reliable communication
Topic: sending an object across a network
Subtopic: goals up

Quote: an ideal electrical communications system permits any person or machine to reliably and instantaneously communicate with any combination of other people or machines, anywhere, anytime, and at zero cost [baraP8_1964a]

Subtopic: communication as reproducing a message up

Quote: a communication system transmits information from a source over a channel, where it is received at its destination [shanCE7_1948]
Quote: communication reproduces a message from a set of possible messages; semantics and meaning are irrelevant [shanCE7_1948]

Subtopic: data center network up

Quote: VL2 network architecture for huge data centers with performance isolation, flat addressing, Valiant load balancing, and Ethernet semantics; all-to-all data shuffle at 94% of maximum possible [greeA3_2011]

Subtopic: session up

Quote: a session is a sequence of messages delivered exactly once; on failure, continue the session on the backup process of a process-pair; on transaction abort, reset to the starting session sequence number [grayJ11_1985]

Subtopic: boundary, state variables, and communication up

Quote: communicate between two Petri nets by identifying peripheral locations [petrCA1_1966]
Quote: printing could be projecting an object across the memory-to-printer barrier, or editing across a memory-to-user barrier [coxBJ7_1983]
Quote: classification view of systems depends on a global perspective; communication view is localized and observable, like Plato's cave dwellers [wegnP10_1986]

Subtopic: communication as memory, state variables up

Quote: make communication look like memory via ports (a queue of buffers), message screening or filtering, and logical addressing [cherDR5_1986]
Quote: an environment and system communicate by changing values of state functions, e.g., voltages on wires [lampL1_1989]
Quote: for problem-oriented shared memory, communication must have efficient/reliable transport, multicast, network data pointers, and process invocation [cherDR5_1986]

Subtopic: noise up

Quote: the noisiness and variability of vocal signals leads to digital communication with discrete units [chriMH10_2008]

Subtopic: electromigration up

Quote: survey of electromigration (EM), the major source of wire failure; metal atoms migrate to triple points; self healing by current flow in both directions [abelJ2_2010]

Subtopic: virtual document up

Quote: a virtual document is active, structured information for communication; applications are tools; e.g., Illustrator format [warnJE6_1992]

Subtopic: wires necessary for computation up

Quote: the old conception of computation treated wires as idealized, instantaneous connections [hillWD_1985]
Quote: in computers, wires are much of the cost, space and delay times [hillWD_1985]
Quote: the router in the bulk-synchronous parallel model sends up to h messages for each component [valiLG8_1990]
Quote: with the bulk-synchronous parallel model, the hardware investment for communication must grow faster than that for computation [valiLG8_1990]

Subtopic: communication drives cost of collaboration up

Quote: communication is main cost of running Netlib; inexpensive to manage [dongJJ5_1987]

Subtopic: programming network switches up

Quote: NetCore defines packet-forwarding policies with set-theoritic operations; classify packets with exact-match bit patterns and wildcards; arbitrary functions to analyze packets and history [monsC1_2012]
Quote: reactive specialization -- unknown packet sent to network controller, analyzed and redirected with new network switch rules for handling this packet type [monsC1_2012]
Quote: Frenetic language for programming distributed collections of network switches; packet-forwarding with functional reactive combinators; fast path packets, fully modular, and declarative queries [fostN9_2011]
Quote: Frenetic queries produce an event stream of network packets that match a pattern; grouped by header fields, split by arrival time or header value, limited by values, and aggregated by number or size of packets [fostN9_2011]
Quote: bit-level data and inlined arrays needed for device-control registers and networked packets; not in Sing# at first [laruJ8_2010]
Quote: an upcall may asks questions about its service; e.g., ask for further data to append to an outgoing packet [clarDD12_1995]

Subtopic: message frame up

Quote: every message has a frame saying this is a message, an implicit, outer message on how to decode the message (implicit), and a meaning [hofsDR_1979]

Subtopic: network driver up

Quote: netmap reduces packet-processing costs with preallocated buffers and multiple packets per system call [rizzL3_2012]

Subtopic: upcalls for communication up

Quote: use up-calls to transfer incoming network data, user input, or status changes to higher level processes; avoids context switches; used for high-performance networks [birrAD_1991]
Quote: "up transfer" and "down transfer" because the Mark I placed electrostatic memory on a lower floor than its magnetic drum and teleprinter [campM4_1980]

Subtopic: sneakernet, physical transfer up

Quote: transfer huge databases by transfering complete computers [grayJ6_2003]

Subtopic: telecomputing up

Quote: users may control a distant computer over a telephone line [turiAM2_1947]

Subtopic: voice vs. data up

Quote: voice and data require different transmission characteristics; voice needs short, bounded delays while data needs reliable delivery [sariS10_1985]

Subtopic: voice latency up

Quote: speed-of-light latency dominates voice-over-IP; need good access latency to stay below 150ms for voice [gettJ1_2012]

Subtopic: network anomaly up

Quote: time series data analysis with discrete wavelet transform (DWT); detect network anomaly by comparing wavelet coefficient energy at different scales [chaoP1_2011]

Subtopic: history up

Quote: redesign telephones and teletypewriters to gain the full benefit of an all-digital communications network [baraP8_1964a]
Quote: from a dead start, a 49-node network can learn to route messages in about a second; 50% of peak capacity; Monte Carlo simulation [boehSP8_1964]
Quote: a network can quickly reconstitute itself after a large number of breaks [boehSP8_1964]
Quote: messages should be routed over paths whose mean lengths approach the shortest possible paths; the total value of all entries for handover number tables approaches the theoritical minimum with network use [boehSP8_1964]

Related up

Group: communication
Group: distributed systems
Group: electronic mail
Group: information
Group: parallel processing
Topic: a single system image
Topic: communicating sequential processes
Topic: computer architecture
Topic: document-centered system
Topic: electronic meetings
Topic: entropy
Topic: interprocess communication
Topic: open systems
Topic: Petri net
Topic: reliability of distributed systems
Topic: remote procedure call
Topic: routing electronic mailing
Topic: translation of data
Topic: security leaks and weaknesses
Topic: synchronous communication through a channel

Subtopics up

boundary, state variables, and communication
communication as memory, state variables
communication as reproducing a message
communication drives cost of collaboration
data center network
message frame
network anomaly
network driver
programming network switches
sneakernet, physical transfer
upcalls for communication
virtual document
voice latency
voice vs. data
wires necessary for computation

Updated barberCB 6/05
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