Design principle of high-speed network TCP / IP and ATM
First chapter introduced
ATM asynchronous transmission mode (asynchronous transfer mode)
IP Internet Protocol (Internet Protocol)
QoS service quality (QUALITY OF Service)
IDN integrated digital network (Integrated Digital Network)
Switches and digital transmission techniques using digital computer control, although circuit switched methods are still used.
Comprehensive refers to exchange and transmission use digital technology.
ISDN integrated business Digital Network (Integrated Service Digital Network)
A integrated digital network IDN that has a wide range of geographic coverage of telephone networks with data transmission capabilities of digital data networks.
Comprehensive refers not only the integration of digital exchange and digital transmission, but also indexed voice and various types of data traffic transmitted and exchanged on the same digital network.
UNI User Network Interface (User-Network Interface)
Frame Relay is a high-speed packet exchange form for a higher speed network that supports up to 2Mbps data rate.
IP-based interconnect network. The following four technologies in the history of the interconnection network have played a key role:
TCP and IP are combined with the interconnect access function with end-to-end control functions. One key point in this agreement design is that it is divided into two protocols: the IP protocol responsible for interconnect access and message transfer and TCP protocol responsible for reliable end-to-end. For applications that do not need reliable delivery, users can use higher efficiency UDP User Data Ravel Protocol (User DataGram Protocol) on the IP protocol. Real-Time Transport Protocol is now used on real-time communication. RTP real-time transport protocols are usually used on IP.
Dynamic Routing Dynamics Dynamic Route Completes two key features. One is that it allows dynamic discovery routing, so that all end systems and routers do not have to configure all end-to-end routes beforehand, and can be reconfigured in the case of network topology. The second item is to adjust the route when you encounter a network congestion and failure, so network load can effectively achieve equalization.
Group exchange for IP-based internet access, including end-to-end protocols and dynamic elevation, etc., are first proposed for packet switched networks. For a wide area data network, grouping techniques are still technically dominated.
Ethernet Ethernet dominates in the local area network.
OSI Open System Interconnection (Open Systems Interconnection)
Integrated Services Architecture. ISA requires the router hardware to support real-time traffic, and it also includes a series of new protocols:
The new version of IPv6 IP is originally designed to expand the Internet address space, but it provides some features that are critical to ISA.
RSVP Resource Reserved Protocol RSVP (Resource Reservation Protocol allows users to reserve resources on interconnects and designated traffic on the network, which refers to in terms of throughput and time delay.
RTP Real-Time Transport Protocol provides mechanisms to transmit image, sound, and other real-time traffic on the interconnect, through this mechanism, real-time traffic can be restored correctly at the destination.
Multi-broadcasting protocols In many cases, multimedia and other real-time traffic are transmitted to multiple destinations simultaneously - this is multicast.
Using these new protocols, ISA-based interoperability can effectively handle system burst traffic, while processing multimedia and real-time traffic at the same time. ATM network
ATM's successful network, several key features have been included:
The internal command is a seven-signal system SS7 developed by ccitt as IDN and ISDN, which can provide resource management based on ATM-based networks. SS7 includes a mechanism for defining, establishing and undo logical connection to manage network resources.
External Command This refers to a user network interface signal for an ATM network, which includes a mechanism to establish and undo connection. This protocol user can define its own traffic characteristics and require the network to complete the service at a specific QoS level.
The physical layer protocol ATM can operate at hundreds of megabytes per second or higher. In order to support such high data rates, strict physical layer transfer regions must be developed. The most important thing in the physical layer status is the Synchronous Digital Synchronous Digital Synchronous Digital Series of ITU-T; It is the synchronous optical network SONET (Synchronous) in the United States.
Optical Network. The standard that maps the ATM layer data to the SDH / SONET layer has been developed.
ATM adaptation ATM is a universal transfer service that can be used to support multiple data transfer services and high-level protocols. To support high-level protocols, the key is to map a variety of high-level protocols and services to the ATM layer.
First part of the agreement and network basics
Chapter 2 Agreement and TCP / IP protocol
TCP / IP is an Internet-based concept that is a framework for developing a complete set of computer communication standards.
Complete typical communication tasks include:
1. This source system must activate a direct data communication channel or tell the communication network of the identity of the destination system;
2, this source system must confirm that the destination system is ready to accept data;
3. File Transfer Running on this source system must confirm that the file management system on the destination system has prepared and store the file for this particular user;
4. If the file format on the source system and destination system is not compatible, one of the file systems must be responsible for completing the conversion functionality of the file format.
Of course, communication is to participate in both parties, so there must be the same hierarchical function set in both systems. Communication between two systems is done by communication between the peer layers in two systems.
