Index



1.1 Networking Fundamental



1.1.1 Definition of Network:


a collection of hardware components and computers interconnected by communications channels that allow sharing of resources and information.


A Map Representation of WWW of Wikipedia


internet map



1.1.2 OSI Model:


The "Open Systems Interconnection Reference Model is the effort at the International Organization for Standardization. It is a prescription of characterizing and standardizing the functions of a communications system in terms of abstraction layers. Similar communication functions are grouped into logical layers. An instance of a layer provides services to its upper layer instances while receiving services from the layer below.


An Illustration of the Functioning of OSI Model:

osi model illustrated


1.1.3 Description of OSI layers:


OSI Model

Data unitLayerFunction
Host
layers
Data7. ApplicationNetwork process to application
6. PresentationData representation, encryption and decryption, convert machine dependent data to machine independent data
5. SessionInterhost communication
Segments4. TransportEnd-to-end connections, reliability and flow control
Media
layers
Packet/Datagram3. NetworkPath determination and logical addressing
Frame2. Data LinkPhysical addressing
Bit1. PhysicalMedia, signal and binary transmission


1.1.4 Example of Protocol:


Layer

OSI protocols

TCP/IP protocols

AppleTalk

Misc. examples

#

Name

7 Application FTAMX.400X.500DAP,
ROSE, RTSEACSE CMIP
NNTPSIPSSIDNS,
FTP, Gopher,HTTP, NFS,
NTP, DHCPSMPP,
SMTP, SNMP, Telnet, RIPBGP
AFPZIPRTMP,NBP HL7Modbus
6 Presentation ISO/IEC 8823, X.226, ISO/IEC 9576-1, X.236 MIMESSLTLSXDR AFP TDIASCIIEBCDICMIDI,
MPEG
5 Session ISO/IEC 8327, X.225, ISO/IEC 9548-1, X.235 Sockets. Session establishment in TCP,RTP ASPADSP,PAP Named pipesNetBIOSSAP,
half duplexfull duplex,
simplexRPC
4 Transport ISO/IEC 8073, TP0, TP1, TP2, TP3, TP4 (X.224), ISO/IEC 8602, X.234 TCPUDPSCTPDCCP
NBF
3 Network ISO/IEC 8208, X.25 (PLP), ISO/IEC 8878, X.223, ISO/IEC 8473-1, CLNP X.233. IPIPsecICMPIGMPOSPF ATP (TokenTalkor EtherTalk) NBFQ.931IS-IS
2 Data Link ISO/IEC 7666,
X.25 (LAPB),Token Bus,
X.222, ISO/IEC 8802-2
LLC Type 1 and 2[9]
PPPSLIPPPTP LocalTalk,AppleTalk Remote Access,PPP 802.3 (Ethernet),
802.11a/b/g/n MAC/LLC,
802.1Q (VLAN),
ATMHDPFDDIFibre Channel,Frame RelayHDLCISL
PPP
Q.921Token RingCDPNDP 
ARP
 (maps layer 3 to layer 2 address),
 ITU-T G.hn DLL
CRCBit stuffingARQData Over Cable Service
Interface Specification (DOCSIS)
1 Physical X.25 (X.21bis,
EIA/TIA-232,
EIA/TIA-449, EIA-530,
G.703)

RS-232, RS-422,STP,
PhoneNet
RS-232Full duplexRJ45V.35,
V.34I.430I.431, T1E1, 10BASE-T100BASE-TX
POTS
,SONETSDHDSL,
802.11a/b/g/n PHYITU-T G.hn PHYController Area NetworkData Over Cable Service Interface Specification (DOCSIS)



Appendix: Mnemonics

osi nemonics
Image Courtesy: The TCP/IP Guide (http://www.tcpipguide.com)

References Links