Comparison between ATM and IP technology

When talking about ATM, you will surely think of IP addresses. With the popularization and application of networks, there are more and more comments on IP and ATM technologies.
The development of IP technology is ten years earlier than that of ATM. Among the various networking technologies, it should be said that it is also an old technology. In fact, ATM and IP have their own advantages. ATM technology is the embodiment of the telecom industry idea, which is reliable, manageable, and road-centric. IP technology is the embodiment of the computer industry idea, and Besteffort is the network available and best effort) and end-to-end. These two technologies have received wide attention from telecom and computer networks. However, when researching, developing, and using ATM and IP technologies, the telecom and computer network camps have different views and perspectives. The telecom industry expects that ATM can integrate its networks to achieve seamless integration of existing telecommunication networks and future networks, including IP networks and third-generation mobile communication networks, to protect investment in existing telecommunication networks; however, the computer wants to use ATM to better support IP addresses to achieve IP QoS.
The length of the Ethernet IP package is not fixed. The delay between the long information package and the short message package varies greatly. This introduces a large delay jitter and is not suitable for real-time services. When users increase, the service quality decreases, resulting in unstable service quality. The fixed-length cells are used in the ATM technology, which makes the packaging and package splitting latency equal, reduces the delay jitter, and reduces the delay value with a small cell length. In addition, ATM uses traffic control technology. Before the connection is established, it uses signaling negotiation to determine whether the customer's service quality requirements can be guaranteed. Only after the network is confirmed can the customer accept the incoming traffic, ensure different service quality for each virtual circuit. This is the true quality of service (QoS ). Of course, ATM also has its inherent defects. The main problems are high cell overhead and network complexity. For an ATM Cell itself, the overhead of the Cell Header exceeds 10%). If the overhead of the ATM adapter layer and higher-level protocols is taken into account, the overhead may exceed 5/48, this is unacceptable for some data services. In addition, traffic control functions such as CAC, UPC, and NPC introduced by the ATM network to support comprehensive services and ensure QoS are provided, the signaling and network management functions of SVC supported by the network are very complex, which not only increases the network cost, but also increases the network complexity.
To make up for the defects of IP technology in terms of service quality, TETF proposes the RSVPResourceReservationProtocol. At present, the transmission distance of gigabit and 10-Gigabit Ethernet technology on single-mode optical fiber is much higher than that of Traditional Ethernet, which is sufficient for the Interconnection Environment between buildings in the park, however, it still seems powerless for man and wan. However, ATM is not limited by any physical structure and is not related to the Data Type transmitted. That is to say, ATM can transmit any form of data information in the world's largest wide area network, which will greatly enhance the vitality of ATM in the high-speed network.
According to the current network upgrading and resizing scheme, Gigabit and 10-Gigabit Ethernet adopts the same frame length, frame format, and media access layer protocol as traditional Ethernet, therefore, you only need to add a gigabit or 10-Gigabit Ethernet Adapter module to the main device of the Traditional Ethernet LAN. This solution protects users' investment in equipment and technology. In the upgrade and expansion scheme of ATM technology, ATM switches are used to form the Network trunk, which is difficult to protect users' existing investments and technologies. The investment in upgrading the atm lan is much higher than that in upgrading the Ethernet. To some extent, this limits the application of ATM technology in desktop systems. From the perspective of service quality control, although 1-gigabit and 10-Gigabit Ethernet have increased the network trunk bandwidth, it still lacks congestion control like Traditional Ethernet technologies, therefore, it often affects users' access to server database data. In contrast, the ATM technology has more advantages in this regard. ATM is connection oriented, and data transmission is performed only after circuit connection. The data transmission speed is fast and the delay is small. Therefore, the service quality on the ATM is guaranteed as necessary.