Network knowledge of high learning

High notes--the Network Knowledge chapter

First, the classification of the network: LAN, metropolitan area Network (city), Wan (inter-city).
Second, LAN protocol:
Ethernet/ieee802.3(Access method CSMA/CD, multi-channel listening, competition)

Development: Fast Ethernet; 802.3u;100m;

Gigabit Ethernet (and ATM Technology Competition): Optical fiber or Super 5 class, 6 class unshielded twisted pair
Token Ring network/ieee802.5:Ring, star, general line; (Disadvantage: complex protocol, large expenditure; advantages: certainty) are mainly based on shielded twisted pair and unshielded twisted pair.
 fddi/Fiber Distributed Data Interface。 Based on fiber optics.
WAN Protocol:

PPP: Point-to-point
ISDN: Integrated Services Digital Network, using telephone lines, including N-isdn narrowband and B-ISDN Broadband
XDSL: Includes HDSL (high-speed symmetric DSL, two pairs twisted pair), SDSL, MVL, ADSL (Asymmetric DSL, copper twisted pair (normal phone line), upload less than download speed）
Other: DDN Digital leased Line, X., FR Frame Relay, ATM asynchronous Transfer mode (up to 622m/s transfer rate, scalable, high transmission quality, suitable for building backbone).
Third, network topology type:
General line: Advantages: Less cable required, easy to lay out, high single-point reliability. Disadvantage: The fault diagnosis is difficult, the site requirements are high.
Star: Advantages: High overall reliability, easy diagnosis, site requirements are not high. Disadvantage: Need more cable, rely on the central node.
Ring: Advantages: Less cable required, suitable for optical fiber. Disadvantages: Poor overall reliability, trouble diagnosis, high site requirements.

Iv. OSI Hierarchy Model:
Witchcraft forgets to pass the Eagle

Physical layer : fully hardware oriented. Rep: Repeater, Hub, modem
Data Link Layer : Establishes a communication link between adjacent nodes. Functions: Encapsulation into frames, flow control, error control, transmission management. Represents the device: bridge, switch.
Network layer : End-to-end to ensure that the information reaches the intended target; the interconnection of the two sides of the communication or heterogeneous network; represents the device: router, layer three switch.
Transport Layer : port to port, ensure data error-free, sequential, no loss, no redundant transmission.
Session Layer : Responsible for managing the communication of remote users and processes. Communication control, checkpoint settings, rebuilding links, security verification, and more.
Presentation Layer : Conventions for data encoding and conversion of local syntax.
Application layer:

Online Baidu to the list of network protocols

Internet Network Protocol (corresponding intranet protocol, based on TCP/IP protocol, used in intranet, using security tools to prevent intrusion, can connect Internet network)
Tcp / ip:


ARP:-----MAC address from IP address; Rarp in turn
Icmp:internet Control Message Protocol, the protocol for sending error reports;
TCP: Transmission Control Protocol, reliable, flow-controlled, full-duplex, application: FTP, Telnet (telnet), SMTP
UDP: User Datagram protocol, unreliable but fast, application: TFTP, SNMP (Simple Network Management Protocol), NFS (Network File system), DNS, BOOTP (bootstrap protocol; Assign dynamic IP address to diskless workstations in LAN), QQ software

VI, network switching technology:
Multiplexing: FDMA, WDMA, TDMA, CDMA frequency-wave time Code Division multiplexing
Network switching technology: circuit switching, storage and forwarding (message exchange), datagram, virtual circuit, ATM
Seven, network storage technology:
DAS, NAS, SAN
RAID Redundancy Technology
Eight, network access technology
ADSL, HFC (fiber and coaxial cable hybrid network), high-speed Ethernet, DDN access (using digital channel transmission, equipment including DTE Terminal, DSU Data business unit, NMC Network Management Center)
Nine, wireless network technology
WiMAX technology, CDMA2000 Telecom, WCDMA Unicom, TD-SCDMA Mobile
Ten, Optical Network technology
AON (Active optical Network), PON (Passive optical network)
XI. Integrated Cabling
Scope: Spanning distance not exceeding 3000m, building area not exceeding 1 million square meters, number of people 50.5 million.
Work Area: Office
Horizontal cabling: Office to weak motor room
Management Room: Weakness room
Vertical: Weak well
Buildings: Buildings and buildings
Between devices:

Network knowledge of high learning