Voice and Data Communication
Elisha Myles
NTC/360
February 21, 2011

In many households can have various setups of a network from basic Internet connections to electronic devices. Here we will explain how one home network system can be achieved with the proper hardware and devices to make it work. In this home network consist of one desktop computer hard wired with Arris Telephone Telephony cable modem and CATV coaxial cable wiring provided by the cable company. The computer is connected to the cable modem through Ethernet connection and also has a telephone line connection. This is also connected using Ethernet wiring to a NETGEAR Wireless N Router (WNR2000) with a Push ‘N’ Connect feature for using WiFi protection that comes in handy because the house also has a laptop that uses a Wireless-N 300 USB adapter and Playstation 3 in a separate room, both are protected by a password, this is important because the wireless will pick up other signals in the neighborhood and it provides security from other people gaining access to the computer.

The differences between Rotary and Dual Tone Multi-frequency phones are with rotary phones or the rotary dial was improvements to the old form of sending telegraph signals in the 1900s. The rotary dial phones was a mounted device on a telephone or switchboard designed to send electrical pulses that corresponded with the number dialed. The design had a finger plate with holes in the top to allow people to put their fingers in it. Rotary referrers to the rotation of the finger plate on the phone as each number is dialed it turns on and off a switch at the telephone company and some are still in use today. As the years went on people worked to find a better way of improving telecommunication The Dual Tone Multi-frequency known as DTMF this provides for telecommunication signals to be sent over analog telephones in a voice frequency band for handsets. The DTMF uses a dial pulse it functions by rapidly disconnecting and re-connecting the person you are calling. Multi-frequency signaling is a group of signaling methods, which uses a mixture of two pure tone (pure sine wave) sounds. Various MF signaling protocols were created using the Bell System and CCITT. The earliest of these were for in-band signaling between switching centers, where long-distance telephone operators used a 16-digit keypad to input the next portion of the destination telephone number sent to the long-distance operator. With the semi-automated and signaling becoming a success in cost and speed using multi-frequency signaling improved how people use their phones without an operator,

The differences in Wide Area Telecommunication Services and Leasing lines is with a Wide Area Telephone Service (WATS) this is a toll service offered to a customer in a station allowing him or her to call someone in the same area for a fee. Each access line can be arranged either outward and inward services or both in most cases. With an inward service the subscriber is given a toll free number to use with an area such as 800, 877, or 844. Leasing lines work in a similar fashion, but are only used in businesses. A lease line connects two locations together for private voice or data telecommunication and only is a reserved circuit between the two points. What makes these different from one another is the leasing line is a single open circuit, WATS it continues to reuse the same lines in a process called “switching.” Businesses like leasing lines because it guarantees bandwidth for the company’s network known as T1 lines.

The differences between Private Branch eXchange (PBX) and Centex are the PBX is more of an in home telephone system with mult-phone extensions. Companies prefer using PBX because it cuts the cost and employees like it because it makes remembering phone numbers much easier. In a Centrex telephone service is set up just like a PBX system, but with PBX the company has to buy and install the equipment and Centrex the telephone company takes on the responsibility of providing equipment, installation, and service is included. Centrex provides a much cheaper alternative compare to PBX especially, with working a budget. Though PBX is expensive it can be cheaper because there are no monthly payments and maintenance is easy on cost. Centrex does not provide all the features that some users look forward to and cost becomes the main issue to add a feature to the phone and PBX users can have as many features as they want.

The International Organization for Standardization-Open Systems Interconnection (ISO-OSI) reference model has been the standard project for communication systems for many years. Comprise of seven layers to show how communication is established in a computer. The model layers are physical, datalink, network, transport, session, presentation, and application. The creators of the model were leaded through universal principles serving to as most effective and as simple as possible division of communication to layers. They tried to minimize the count of layers, create a unique section for alternative functions and must work without any problems.
Layer 7-Phyiscal: The Physical layer concerns itself with the transmission of bits. It also manages the network card's hardware interface to the network. The hardware interface involves the type of cabling such as coax, twisted pair with frequency of operation1 Mbps, 10Mbps.
Layer 6-Datalink: The Data Link layer is a firmware layer of the network interface card. The Data Link layer puts the datagrams into packet frames of bits: 1s and 0s for transmission, and assembles received packets into datagrams. The Data Link layer works at the bit level, and adds start or stop flags and bit error checking to the packet frame. Error checking is at the bit level only: packets with errors are discarded and a request for re-transmission is sent out and is primarily concerned with bit sequence.
Layer 5-Network: The Network layer is concerned with the path through the network. It’s responsible for routing, switching, and controlling the flow of information between hosts. The Network layer converts the segments into smaller datagrams than the network can handle: network hardware source and destination addresses are also added though it is not guarantee that the datagram will reach its destination.
Layer 4-Transport: The Transport layer provides error checking at the segment level (frame control sequence). This makes sure that the datagrams are in the correct order the transport layer will correct out of order datagrams. The Transport layer guarantees an error-free host to host connection. It’s not concerned with the path between machines. In order for the data to be sent across the network, the file must be broken up into usable small data segments between 512 - 18K bytes. The layer breaks up the file into segments for transport to the network, and combines incoming segments into a contiguous file this process is done logically, not physically, and it is done in software as opposed to hardware.
Layer 3-Session: The Session layer manages the communications between the workstation and the network. The layer directs the information to the correct destination, and identifies the source to the destination and identifies the type of information as data or control. The Session layer manages the initial start-up of a session, and the orderly closing of a session
Layer 2-Presentation:The presentation layer is the sixth layer of the OSI model. It responds to service requests from the application layer and issues service request to the session layer. The layer performs certain functions requests sufficiently often to finding a general solution for users, rather than letting each user solve the problems. In particular, unlike all the lower layers, which are just interested in moving bits reliably from here to there, the presentation layer is concerned with the syntax and semantics of the information transmitted. Sometimes called the syntax layer in the OPEN SYSTEMS INTERCONECTION MODEL (OSI) is basically used to address and resolve data communication across the 7 layers Layer 1-Application: The application layer is the OSI layer closest to the end user, which means that both the OSI application layer and the user interact directly with the software application. This layer interacts with software applications that implement a communicating component. Such application programs fall outside the scope of the OSI model. Application layer functions typically include identifying communication partners, determining resource availability, and synchronizing communication. When identifying communication partners, the application layer determines the identity and availability of communication partners for an application with data to transmit. References componentworking.about.com. (February 20, 2011). leased line. Retrieved from http://componentworking.about.com/od/networkcables/g/bldef_leasedin.htm www. reference.com. (Febuarary 20, 2011). Wide Area Telecommunication Service. Retrieved from http://www.reference.com/browse/Wide+Area+Telecommunications+Service www.collocationcenter.eu. (Febuarary 20. 2011). ISO/OSI Model. Retrieved from http://www.collocationcenter.eu/iso-osi.html www.differencesbetween.net. (February 20,v2011). Differences Between PBX and Centrex. Retrieved from http://www.differencesbetween.net/technology/difference-between-pbx-and-centrex