Tuesday, 12 August 2014



Paper band broadcast operation at US FAA's Honolulu flight account base in 1964
Punched band was acclimated as a way of autumn letters for teletypewriters. Operators typed in the bulletin to the cardboard tape, and again beatific the bulletin at the best band acceleration from the tape. This acceptable the abettor to adapt the bulletin "off-line" at the operator's best accounting speed, and acceptable the abettor to actual any absurdity above-mentioned to transmission. An able abettor could adapt a bulletin at 135WPM (words per minute) or added for abbreviate periods.
The band about operated at 75WPM, but it operated continuously. By advancing the band "off-line" and again sending the bulletin with a band reader, the band could accomplish continuously rather than depending on affiliated "on-line" accounting by a individual operator. Typically, a individual 75WPM band accurate three or added buzzer operators alive offline. Tapes punched at the accepting end could be acclimated to broadcast letters to addition station. Large abundance and advanced networks were developed application these techniques.
Paper band could be apprehend into computers at up to 1000 characters per second.[5]

Software on fanfold cardboard band for the Abstracts General Nova minicomputer.
When the aboriginal minicomputers were getting released, a lot of manufacturers angry to the absolute banal ASCII teleprinters (primarily the Buzzer Model 33, able of 10 ASCII characters per additional throughput) as a bargain band-aid for keyboard ascribe and printer output. The frequently defined Model 33 ASR included a cardboard band punch/reader, area ASR stands for "Automatic Send/Receive" as against to the punchless/readerless KSR - Keyboard Send/Receive and RO - Receive Alone models. As a ancillary effect, punched band became a accepted average for low amount minicomputer abstracts and affairs storage, and it was accepted to acquisition a alternative of tapes absolute advantageous programs in a lot of minicomputer installations. Faster optical readers were aswell common.
BINARY abstracts alteration to or from these minicomputers was generally able application a doubly encoded address to atone for the almost top absurdity amount of punches / readers. The low-level encoding was about ASCII, added encoded and affected in assorted schemes such as Intel Hex - in which a bifold amount of "01011010" would be represented by the ASCII characters "5A". Framing, acclamation and checksum (primarily in ASCII hex characters) advice provided absurdity apprehension capabilities. Efficiencies of such an encoding arrangement are on the adjustment of 35-40% (e.g., 36% from 44 8-bit ASCII characters getting bare to represent 16 bytes of bifold abstracts per frame).
Data alteration for ROM and EPROM programming[edit]
In the 1970s through the aboriginal 1980s, cardboard band was frequently acclimated to alteration bifold abstracts for assimilation in either mask-programmable read-only anamnesis (ROM) chips or their erasable counterparts - EPROMs. A cogent array of encoding formats were developed for use in computer and ROM/EPROM abstracts transfer.[6] Encoding formats frequently acclimated were primarily apprenticed by those formats that EPROM programming accessories accurate and included assorted ASCII hex variants as able-bodied as a amount of computer-proprietary formats.
A abundant added archaic as able-bodied as a abundant best high-level encoding arrangement was aswell acclimated - BNPF (Begin-Negative-Positive-Finish). In BNPF encoding, a individual byte (8 bits) would be represented by a awful bombastic appearance framing arrangement starting with a individual ASCII "B", eight ASCII characters area a "0" would be represented by a "N" and a "1" would be represented by a "P", followed by an catastrophe ASCII "F". These ten-character ASCII sequences were afar by one or added whitespace characters, accordingly application at atomic 11 ASCII characters for anniversary byte stored (9% efficiency). The ASCII "N" and "P" characters alter in four bit positions, accouterment able aegis from individual bite errors. Alternative schemes were aswell accessible area "H" and "L" or "0" and "1" were aswell accessible to represent abstracts bits, but in both of these encoding schemes, the two data-bearing ASCII characters alter in alone one bit position, accouterment actual poor individual bite absurdity detection.
Cash registers[edit]
National Banknote Register or NCR (Dayton Ohio) fabricated banknote registers about 1970 that would bite cardboard tape. The band could again be apprehend into a computer and not alone could sales advice be summarized, billings could be done on allegation transactions.
Newspaper industry[edit]
Punched cardboard band was acclimated by the bi-weekly industry until the mid-1970s or later. Newspapers were about set in hot advance by accessories such as a linotype. With the wire casework advancing into a accessory that would bite cardboard tape, rather than the linotype abettor accepting to retype all the admission wire stories, the cardboard band could be put into a cardboard band CLAIRVOYANT on the linotype and it would actualize the advance slugs afterwards the abettor re-typing the stories. This aswell accustomed newspapers to use devices, such as the Friden Flexowriter, to catechumen accounting to advance blazon via tape. Even afterwards the annihilation of the Linotype/hot lead, abounding aboriginal "offset" accessories had cardboard band readers on them to aftermath the news-story copy.
Automated machinery[edit]

Paper band CLAIRVOYANT on a computer after ascendancy (CNC) machine.
In the 1970s, computer-aided accomplishment accessories generally acclimated cardboard tape. Cardboard band was a actual important accumulator average for computer-controlled wire-wrap machines, for example. A cardboard band clairvoyant was abate and abundant beneath big-ticket than hollerith agenda or alluring band readers. Premium atramentous waxed and anointed long-fiber papers, and Mylar blur band were invented so that assembly tapes for these machines would endure longer.
Paper band was the base of the Vernam cipher, invented in 1917. During the endure third of the 20th century, the National Aegis Agency acclimated punched cardboard band to deliver cryptographic keys. The 8-level cardboard tapes were broadcast beneath austere accounting controls and were apprehend by a ample device, such as the duke captivated KOI-18, that was briefly affiliated to anniversary aegis accessory that bare new keys. NSA has been aggravating to alter this adjustment with a added defended cyberbanking key administration arrangement (EKMS), but cardboard band is allegedly still getting employed.

Fanfold cardboard tape.
Paper band canister[edit]

Paper Band Canister
The cardboard band brazier is a alter aggressive alembic from which the capacity may manually be dispensed but which prohibits reinsertion of a band already removed. It was acclimated to deeply deliver cryptographic keys. Distributing cryptographic keys in the accessible larboard the keys vulnerable. “Putting band in canisters apparent a lot of the aegis botheration by absorption the vulnerability to the point of use rather than the able time in inventory”, said Whitfield Diffie. The brazier was invented to anticipate the adeptness to alter with the cardboard band already placed central the canister. One of the primary users of the Cardboard Band Brazier was the National Aegis Agency. The NSA bare the adeptness to alteration crytographic keys in a way that cleary showed if the keys had been compromised.

paper band canister, tampered with
The cardboard band brazier to the larboard has acutely been tampered with. The cardboard band has been aloof from the brazier and an attack to reinsert the band has failed. The encrypted keys accept been disrupted; accordingly they could be biased or exploited. The cardboard band brazier has several tamper-proof architecture features:
Hugh V. Hayes, the inventor, wrote
Every cardboard band brazier is unique. This character is able during the accomplishment process, the artificial abounding into the cast creates different breeze patterns throughout the absolute cardboard band brazier thereby authoritative it absurd to alike eliminating the achievability of substitution.
Welded Seam
The anchored bond ensures that the cardboard band brazier cannot be pried accessible afterwards getting detected.
Beaded Seam
Is a different bond that is harder to alike thereby authoritative it difficult to duplicate.
Maze-like Cardboard Path
The cardboard aisle will not acquiesce the reinsertion of tape.

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