There are five essential elements to the most basic construction of an airline reservation. Virtually all CRS (Computer Reservation Systems) or GDS (Global Distribution Systems) are based upon a similar architecture. (although some have now chosen to ignore one element due to it not being used effectively by individuals using the systems). The first element is the Itinerary: From where is the passenger departing and what is their destination? How many passengers will there be? When do they wish to travel -And- when (if) are they returning. The second element is the Name of the passenger(s). Surname/First name/Title (SHK, LDY,LRD,HRH,REV,CAPT, MSTR, MR,MRS,MISS, DR., etc. The third element is the Phone Contact details. How is the airline or travel agent to contact the passenger should there be a delay in the flight. What is the Home number, the Work Number, or Mobile number and even possibly the hotel number where the passenger is staying: CTCH, CTCB, CTCM,CTCH The fourth element is the Ticketing information. When will the passenger call for the ticket (TAW/22JUN), has it already been ticketed (T./), must it be ticketed by a certain date (TTL/22JUN), etc. The last essential element to the architecture is called the 'Received' Field. (R.) Essentially, you're documenting who, precisely was it who instructed you to charge £5,000 to their credit card. Was it the passenger to whom you were speaking, was it the passenger's secretary, was it the wife, or even possibly the girlfriend. At the launch of airline reservation systems, they were creatively designed to address virtually every contingency, permitting a cross-section of cultures and languages to effectively communicate without the necessity of learning different languages. The language used demanded precise adherence and time after time, it proved itself. In fact, airline staff beginning careers in the airline's reservation departments were not permitted to have pens, pencils, or sheets of paper. The reservation system before them was so well designed, under not only the guidance of individual international airlines, but NATO, MOD, and CIA input was used as well. Unfortunately, when the airline systems were first introduced to travel agencies as a work tool, the airlines were no longer able to effectively enforce college-educated staff utilising the data systems correctly and due to the appalling number of errors being made by travel agents, leaving the airlines to try and sort out thousands of miles down-line, quick steps had to be taken to 'dumb down' the booking process for the agent community. In many cases, it still presented so many problems that some airlines simply refused to let blocks of agencies have access to their reservation systems. This was the launch point for commercial CRS systems sold or leased to retail travel agencies. Teaching the travel agents required simple tools to help staff cope with the complexities of making an airline booking. The initial architecture presented the acronym PRINT. P = The Phone Number of the passenger R = Who told you to make this booking, cancel the booking, change it., etc. I = The itinerary. Where is the passenger going? N = What is the name of the passenger (s) T = When must the ticket be issued. Virtually anything else beyond the above were considered ancillary elements to the basic architecture. For example: Imperative statements or SSR's (Special Service Requests) were specific instructions entered into the computer, telling the airline to do something that required action: Ordering a meal, wheelchair, etc. And Non-imperatives, or 'other service information' (OSI), provided non-actionable information that the airline would not see until the passenger is checking in for the flight.... Sample OSI's include: DEAF - passenger is deaf, TCP4 TW 2.Jones/George/Carla - this booking is to complete a part of 4 travelling together, the passenger on this PNR (passenger name record) is travelling with George and Carla Jones. OSI JFK CTCH 212 759 3000 - Plaza Hotel = passenger when in New York is staying at the Plaza Hotel. OSI GIG CTCH - 74 55 2933 - Copacabana = whilst in Rio passenger is staying at the Copacabana Hotel.
Protocol is the special set of rules that end points in a telecommunication connection use when they communicate. In other words Protocol is an agreed-upon format for transmitting data between two devices. The protocol determines the following: * the type of error checking to be used * data compression method, if any * how the sending device will indicate that it has finished sending a message * how the receiving device will indicate that it has received a message Service is a program, routine, or process that performs a specific system function to support other programs, particularly at a low (close to the hardware) level
1. Protocol layering is a common technique to simplify networking designs by dividing them into functional layers, and assigning protocols to perform each layer's task. For example, it is common to separate the functions of data delivery and connection management into separate layers, and therefore separate protocols. Thus, one protocol is designed to perform data delivery, and another protocol, layered above the first, performs connection management. The data delivery protocol is fairly simple and knows nothing of connection management. The connection management protocol is also fairly simple, since it doesn't need to concern itself with data delivery. 2. Protocol layering produces simple protocols, each with a few well defined tasks. These protocols can then be assembled into a useful whole. Individual protocols can also be removed or replaced as needed for particular applications. The most important layered protocol designs are the Internets original DoD model, and the OSI Seven Layer Model. The modern Internet represents a fusion of both models. 1. Protocol layering is a common technique to simplify networking designs by dividing them into functional layers, and assigning protocols to perform each layer's task. For example, it is common to separate the functions of data delivery and connection management into separate layers, and therefore separate protocols. Thus, one protocol is designed to perform data delivery, and another protocol, layered above the first, performs connection management. The data delivery protocol is fairly simple and knows nothing of connection management. The connection management protocol is also fairly simple, since it doesn't need to concern itself with data delivery. 2. Protocol layering produces simple protocols, each with a few well defined tasks. These protocols can then be assembled into a useful whole. Individual protocols can also be removed or replaced as needed for particular applications. The most important layered protocol designs are the Internets original DoD model, and the OSI Seven Layer Model. The modern Internet represents a fusion of both models.
Presentation Layer
ISO stands for International standards organization.It is an organization for agreement on international standards of network communication world wide. On the other hand OSI is a model for understanding and designing a network architecture.
There are in total seven layers in OSI model . OSI model layer that is responsible for the termination of connections between hosts is session layer . Session layer is responsible for the dialog control .
The OSI (Open Systems Interconnect) 7-layer model is based, in-part, on standards published by the IEEE (Institute of Electrical and Electronics Engineers). For example, IEEE standard 802.3 describes Ethernet. In the OSI model, the 802.3 standard exists at layers 1 and 2. ANSWER IEEE is a standards organization to which many hardware and software suppliers both contribute to and agree to use 'standardized' techniques. Ethernet is but only ONE of the many standards, and the OSI is only one of the usage standards.
International Standards Organization(ISO)
Physical layer which is the first layer in OSI reference model is responsible for signal encoding and decoding.
Physical
physical
OSI model
what osi layer is responsible for routing, message fragmentation, and reasembly
The OSI model is given by international standards organization. The OSI model is given so that regardless of the underlying architecture system can communicate with each other. The correct order of layer is Application, presentation , session , transport, network , data link and physical.
The Open Systems Interconnect or OSI model has seven layers. The layer that is responsible for creating frames is the Data Link layer.