In the OSI (Open System Interconnections) Model, each layer uses the services of the layer below it and provides services to the layer above it. The primary function of the data link layer is to provide a well-defined service interface to the network layer above it. Virtual Communication versus Actual Communication The main service provided is to transfer data packets from the network layer on the sending machine to the network layer on the receiving machine. Data link layer of the sending machine transmits accepts data from the network layer and sends them to the data link layer of ... Read More

The data link layer in the OSI (Open System Interconnections) Model, is in between the physical layer and the network layer. This layer converts the raw transmission facility provided by the physical layer to a reliable and error-free link. The main functions and the design issues of this layer are Providing services to the network layer Framing Error Control Flow Control Services to the Network Layer In the OSI Model, each layer uses the services of the layer below it and provides services to the layer above it. The data link layer uses the services offered by the ... Read More

The network data link layer is the layer above the physical layer in the Open System Interconnections (OSI) model. The primary concern of this layer is to convert the raw transmission facility provided by the physical layer to a reliable and error-free link.In TCP/IP model, the physical layer and the data link layer are combined as the host - to - network layer. Data Link Layer in the OSI Model The Open System Interconnections (OSI) model is a layered networking framework that conceptualizes how communications should be done between heterogeneous systems.Its three lower OSI layers are called the network support ... Read More

The network physical layer is the lowest network layer in the Open System Interconnections (OSI) model. The primary concern of this layer is transmission of individual bits from one node to another over a physical medium. In TCP/IP model, the physical layer and the data link layer are combined as the host - to - network layer. Physical Layer in the OSI Model The Open System Interconnections (OSI) model is a layered networking framework that conceptualizes how communications should be done between heterogeneous systems. The physical layer is its lowest layer. The following diagram depicts the position of the physical ... Read More

In U.S. telecommunications,Local access and transport area (LATA) refers to a geographical area in the U.S. which is allocated to telephone companies. The telephone companies, legally termed as local exchange carriers (LECs) provide telecommunication services, within the allotted areas. A LATA may be within the same U.S. state or may span across more than one state, as laid down in Telecommunications Act of 1996. Two types of connections are possible. IntraLATA − It is a connection between two LECs within the LATA. InterLATA − It is a connection providing long-distance service between LECs in different LATAs.

Definitions Cable − Cable network is a system of providing varied services like television programming, FM programming, Internet and telephone services over existing cable TV network. ADSL − Asymmetric Digital Subscriber Line (ADSL) is a type of broadband communications technology to transmit digital data at a high bandwidth on existing phone lines to homes and businesses. Fiber − Fiber or Fiber to the home (FTTH) is a technology to deploy optical fibers in the local loop of the telephone networks to the users home for providing high-speed data connectivity. Comparisons Wires Cable − They use the copper coaxial ... Read More

A network interface device (NID), also called network interface unit (NIU), is an interface between the network provider's local loop and the customer. These are present as grey boxes outside customer's premises, where the data wires of the phone company or the network provider ends and the customer's wiring begins. Diagrammatic Representation Features NID demarcates between provider's connection and customer's connection. Maintenance of wiring of the local loop up to the NID is the responsibility of the phone provider, while maintenance of wiring from the NID to the customer premises is the responsibility of the customer. NID protects ... Read More

Definitions Circuit Switched Networks − Circuit switched networks are connection-oriented networks. Here, a dedicated route is established between the source and the destination and the entire message is transferred through it. Packet Switched Networks − Packet switched networks are connectionless networks. Here, the message is divided and grouped into a number of units called packets that are individually routed from the source to the destination. Comparisons Differences with respect to technology Serial Number Circuit – Switching Packet – Switching 1 It is a connection oriented network switching technique. It is a connectionless network switching technique. ... Read More

ADSL −Asymmetric Digital Subscriber Line (ADSL) is a type of broadband communications technology to transmit digital data at a high bandwidth on existing phone lines to homes and businesses.Cable − Cable network is a system of providing varied services like television programming, FM programming, Internet and telephone services over existing cable TV network.Comparison of ADSL and Cable NetworksADSL uses the existing telephone lines for providing data, voice and multimedia services, while cable uses existing cable TV networks to provide similar services.Both ADSL and cable networks use fiber optic cables in their backbone. However, in the customer end, cable network uses ... Read More

Data over cable service interface specification (DOCSIS) is an international telecommunications standard to provide high speed data to cable TV system over its existing hybrid fiber-coaxial (HFC) infrastructure. It is used for providing cable Internet access as well as supporting high definition televisions. Versions of DOCSIS DOSCIS 1.0 − It was the first version for cable modem system DOSCIS 2.0 − It enhanced upstream data from computer to the operator to allow services requiring equal data transfer in both uplink and downlink, like IP telephony. DOSCIS 3.0 − It supports IPv6 standard. It is marked by increase in transmission ... Read More