barcode project in vb.net Protocols in Software

Creator Code 39 in Software Protocols

Protocols
Decode Code39 In None
Using Barcode Control SDK for Software Control to generate, create, read, scan barcode image in Software applications.
Printing Code 39 In None
Using Barcode printer for Software Control to generate, create Code 39 Extended image in Software applications.
Figure 2-29 Meshed network; five users, ten circuits
Decode Code 3 Of 9 In None
Using Barcode recognizer for Software Control to read, scan read, scan image in Software applications.
ANSI/AIM Code 39 Creator In Visual C#
Using Barcode generation for .NET Control to generate, create Code 39 Extended image in .NET applications.
2
Making Code39 In .NET
Using Barcode encoder for ASP.NET Control to generate, create Code 39 Extended image in ASP.NET applications.
Code 39 Generation In .NET Framework
Using Barcode printer for .NET Control to generate, create Code-39 image in .NET applications.
installed all to allow 2,000 people to call each other. Obviously, some alternative solution was greatly needed. That solution was the switch. The first switches did not arrive until 1878 with the near-disastrous hiring of young boys to work the cord boards in the first central offices. John Brooks, author of Telephone: The First 100 Years, offers the following:
Encoding Code 3 Of 9 In VB.NET
Using Barcode generation for .NET framework Control to generate, create Code 3 of 9 image in .NET applications.
Draw GS1 - 13 In None
Using Barcode encoder for Software Control to generate, create EAN-13 image in Software applications.
The year of 1878 was the year of male operators, who seem to have been an instant and memorable disaster. The lads, most of them in their late teens, were simply too impatient and high spirited for the job, which, in view of the imperfections of the equipment and the inexperience of the subscribers, was one demanding above all patience and calm. According to the late reminiscences of some of them, they were given to lightening the tedium of their work by roughhousing, shouting constantly at each other, and swearing frequently at the customers. An early visitor to the Chicago exchange said of it, The racket is almost deafening. Boys are rushing madly hither and thither, while others are putting in or taking out pegs from a central framework as if they were lunatics engaged in a game of fox and cheese. It was a perfect bedlam.
ANSI/AIM Code 39 Creation In None
Using Barcode creation for Software Control to generate, create Code 3 of 9 image in Software applications.
EAN128 Drawer In None
Using Barcode printer for Software Control to generate, create UCC.EAN - 128 image in Software applications.
Later in 1878 the boys were grabbed by their ears and removed from their operator positions, replaced quickly and, according to a multitude
Barcode Maker In None
Using Barcode drawer for Software Control to generate, create bar code image in Software applications.
Paint Barcode In None
Using Barcode encoder for Software Control to generate, create bar code image in Software applications.
Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website.
Draw Code 93 In None
Using Barcode creator for Software Control to generate, create USD-3 image in Software applications.
Data Matrix 2d Barcode Creator In .NET
Using Barcode maker for ASP.NET Control to generate, create Data Matrix 2d barcode image in ASP.NET applications.
Protocols
Reading Data Matrix 2d Barcode In .NET Framework
Using Barcode reader for Visual Studio .NET Control to read, scan read, scan image in .NET applications.
Bar Code Maker In Java
Using Barcode maker for Android Control to generate, create barcode image in Android applications.
Protocols
GS1 128 Creator In Java
Using Barcode drawer for Eclipse BIRT Control to generate, create EAN 128 image in BIRT reports applications.
Drawing Universal Product Code Version A In Java
Using Barcode creator for Android Control to generate, create UCC - 12 image in Android applications.
of accounts, to the enormous satisfaction of the customers by women, shown in Figure 2-30. These operators were, in fact, the first switches. Now, instead of needing a dedicated circuit running from every customer to every other customer, each subscriber needed a single circuit that ran into the central exchange, where it appeared on the jack field in front of an operator (each operator managed approximately 100 positions, the optimum number according to Bell System studies). When a customer wanted to make a call, he or she would crank the handle on the phone, generating current which would cause a flag to drop, a light to light or a bell to ring in front of the operator. Seeing the signal, the operator would plug a headset into the customer s jack appearance and announce that she was ready to receive the number to be dialed. The operator would then simply crossconnect the caller to the called party, then wait for the receiver to be picked up on the other end. The operator would periodically monitor the call and pull the patch cord down when the call was complete. Incidentally, note the roller skates on the feet of the supervisors. The cord boards were so long that the process of collecting tickets took far too long, so they added mobility! This model meant that instead of needing 3,997,999 circuits to provide universal connectivity for a town of 2,000 people, 2,000 were needed a rather significant reduction in capital outlay for the telephone company, wouldn t you say Instead of looking like Figure 2-29, the network now looked like Figure 2-31.
Print Barcode In Visual Basic .NET
Using Barcode creator for VS .NET Control to generate, create bar code image in .NET framework applications.
Printing EAN13 In None
Using Barcode drawer for Online Control to generate, create EAN13 image in Online applications.
Figure 2-30 First women operators (Courtesy Lucent Technologies)
Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website.
Protocols
Figure 2-31 Switched network; five users, five circuits
2
Over time, manual switching slowly disappeared, replaced by mechanical switches initially followed by more modern all-electronic switches. The first true mechanical switches didn t arrive until 1892, when Almon Strowger s Step-by-Step switch was first installed by his company, Automatic Electric. Strowger s story is worth telling because it illustrates the serendipity that characterized so much of this industry s development. It seems that Almon Strowger was not an inventor, nor was he a telephone person. He was, in fact, an undertaker in a small town in Missouri. One day, he came to the realization that his business was (OK, I won t say dying) declining, and upon closer investigation determined that the town s operator was married to his competitor! As a result, any calls that came in for the undertaker naturally went to her husband and not to Strowger. To equalize the playing field, Strowger called upon his considerable talents as a tinkerer and designed a mechanical switch and dial telephone, which is still in use today in a number of developing countries. The bottom line to all this is that switches create temporary end-toend paths between two or more devices that wish to communicate with each other. They do it in a variety of ways; circuit-switched networks create a virtually dedicated path between the two end points and offer constant end-to-end delay, making them acceptable for delay-sensitive
Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website.
Copyright © OnBarcode.com . All rights reserved.