Asynchronous Transfer Mode Node

• Buffer
• Tweet

The asynchronous transfer mode (ATM) is part of an International Telecommunication standard for cell relay for voice, data and video with varying bit-rate, which was developed for both local and wide area networks (LAN and WAN). The ATM node system, also called the ATM switching system, is an important element in broadband and narrowband services. The ATM is a cell-based switching technique using asynchronous methods. ATM establishes a virtual circuit between two endpoints before exchanging data. The source node is where the message originates.

Packet switching supports uneven amounts of data traffic. Asynchronous transfer mode uses the bandwidth efficiently while dealing with more than one kind of data traffic. Because of its high-speed packet switching technology, ATM supports real-time voice and video.

The fact that this transfer mode is asynchronous means that sources are not limited to sending data at a particular time. In other switching technologies, such as T1, there is this limitation. ATM transmits data in packets, called cells. The fixed size packet cuts down on processing time and switching delays. The small size of the cells, 53 bytes, provides fast transmission of data. The cells have two parts, the header and the payload. The cells exchange alarm and connectivity information between nodes. Cells travel down a virtual path through the ATM switches in the ATM network.

When a network user tries to connect to another network user, the ATM switches use signaling protocols to “talk” to one another about available resources for the connection. ATM technology uses an adaptation layer to support information transfer protocols not based on ATM. This layer segments and reassembles packets into ATM cells.

When a request arrives at the entrance of the ATM network, there are two possibilities for routing, either hop- to-hop routing or source node routing. In hop-to-hop routing, each node in the path inspects the address and makes a forwarding decision based on this address. In source node routing the entrance node specifies the complete path to the destination. The remaining nodes on the path make no routing decisions.

Data traffic tends to be erratic, that is, it does not need to communicate for an extended period of time and then it needs to communicate large quantities of information as fast as possible. Voice and video generally are more even in the amount of information required. This media requires knowledge of when and in what order the information will arrive at the intended destination. ATM is the only standards-based technology that was intended to allow the simultaneous transmission of data, voice and video. While some other technologies can tolerate an increase in one of the factors involved, such as the size, bit-rate or number of users, ATM remains the only technology that can handle all changes in bit-rate, network size and in the number of users.

The hallmark of ATM is the flexibility it provides in handling a large variety of data traffic. This results in significant benefits to users, designers and network administrators. ATM makes it possible for network transport functions to be separated into two categories: individual, logical or virtual connections and those related to a group of logical connections, that is, a virtual path. This simplifies network management. There is also improved efficiency and manageability because a single network can carry voice, data and video.

Resource by Will

I am the editor for TheFreeResource.com, and owner of LinchpinSEO, a small business content creation company. The Free Resource has a select community of talented writers, teachers, and business people (and we are always looking for more) that bring you the most trusted resources on the web and credible articles about many topics.

Related Research For Teachers, Students, and Kids