Network Protocols and Communications

RULES OF COMMUNICATION

OVERVIEW OF THE SEGMENTING PROCESS
The size restrictions of frames require the source host to break a long message into individual pieces (or segments) that meet both the minimum and maximum size requirements
Each segment is encapsulated in a separate frame with the address information, and is sent over the network
At the receiving host, the messages are de-encapsulated and put back together to be processed and interpreted
BENEFITS	DRAW-BACKS
Different conversations can be interleaved Increased reliability of network communications	Increased level of complexity

NETWORK PROTOCOLS
• How the message is formatted or structured
• The process by which networking devices share information about pathways with other networks
• How and when error and system messages are passed between devices
• The setup and termination of data transfer sessions

INTERACTION OF PROTOCOLS
• Application Protocol	Hyper Text Transfer Protocol	HTTP
• Transport Protocol	Transmission Control Protocol	TCP
• Internet Protocol	Internet Protocol	IP
• Network Access Protocols	Data link & physical layers

CREATION OF INTERNET, DEVELOPMENT OF TCP/IP
The first packet switching network and predecessor to today's Internet was the Advanced Research Projects Agency Network (ARPANET), which came to life in 1969 by connecting mainframe computers at four locations
ARPANET was funded by the U.S. Department of Defence for use by universities and research laboratories. Bolt, Beranekand Newman (BBN) was the contractor that did much of the initial development of the ARPANET, including creating the first router known as an Interface Message Processor (IMP)
In 1973, Robert Kahn and Vinton Cerf began work on TCP to develop the next generation of the ARPANET. TCP was designed to replace ARPANET's current Network Control Program (NCP)
In 1978, TCP was divided into two protocols: TCP and IP. Later, other protocols were added to the TCP/IP suite of protocols including Telnet, FTP, DNS, and many others

TCP/IP	ISO	AppleTalk	Novell Netware
HTTP DNS DHCP FTP	ACSE ROSE TRSE SESE	AFP	NDS
TCP UDP	TP0 TP1 TP2 TP3 TP4	ATP AEP NBP RTMP	SPX
IPv4 IPv6 ICMPv4 ICMPv6	CONP/CMNS CLNP/CLNS	AARP	IPX
Ethernet PPP Frame Relay ATM WLAN

SUMMURY
The TCP/IP network access layer is the equivalent of the OSI data link layer (Layer 2) and the physical layer (Layer 1)
The OSI physical layer provides the means to transport the bits that make up a data link layer frame across the network media
Physical layer standards address three functional areas: physical components, frame encoding technique, and signalling method
Using the proper media is an important part of network communications. Without the proper physical connection, either wired or wireless, communications between any two devices will not occur
Wired communication consists of copper media and fibre cable
There are three main types of copper media used in networking: unshielded-twisted pair (UTP), shielded-twisted pair (STP), and coaxial cable. UTP cabling is the most common copper networking media
Optical fibre cable has become very popular for interconnecting infrastructure network devices. It permits the transmission of data over longer distances and at higher bandwidths (data rates) than any other networking media
Wireless media carry electromagnetic signals that represent the binary digits of data communications using radio or microwave frequencies

APPLICATION LAYER

Web
HTTP

Name System
DNS

represents data to the user, plus encoding and dialog control

TRANSPORT Layer

TCP

UDP

supports communication between diverse devices across diverse networks

INTERNET LAYER

Routing Protocols
RIP	OSPF	EIGRP	BGP

IP System
ICPM

IP
NAT

determines the best path through the network

NETWORK ACCESS LAYER

Interface Drivers

Ethernet

PPP

ARP

controls the hardware devices and media that the network

The key parallels are in the transport and network layer

OSI MODEL
#	LAYER		DESCRIPTION	PDU	PROTOCOLS
7	Application	H	Network process to application	Data	DNS, WWW/HTTP,P2P, EMAIL/POP, SMTP, Telnet, FTP recognizing data
6	Presentation	H	Data representation and encryption	Data	HTML, DOC, JPEG, MP3, AVI
5	Session	H	Inter host communication	Data	Sockets, Session establishment in TCP, SIP, RTP RPC - Named pipes.
4	Transport	H	End-to-end connections and reliability	Segments	TCP, UDP, SCTP, SSL, TLS
3	Network	M	Path determination and logical addressing	Packets	IP, IPsec, ICMP, IGMP, OSPF,DHCP
2	Data Link	M	Destination and Source Physical addressing	Frames	Ethernet, PPP, 802.11, MAC/LLC, VLAN, ATM, HDP, Fibre Channel Frame Relay, HDLC
1	Physical	M	Media signal and binary transmission	Bits	Q.921, Token Ring, ARP, RS-232, RJ45, V.34, 100BASE-TZ, SDH, DSL, 802.11
• H : Host Layers • M : Media Layers

OPEN STANDARDS		PHYSICAL LAYER
The Internet Society	ISCO	IAB
The Internet Architecture Board	IAB	IETF, IRTF
The Internet Engineering Task Force	IETF	IESG
Institute of Electrical and Electronics Engineers	IEEE	802.3: Ethernet 802.11: Wireless LAN (WLAN) & Mesh (Wi-Fi certification), Uses CSMA/CA 802.15: Bluetooth, Supports speeds up to 3 Mb/s, Provides device pairing over distances from 1 to 100 meters 802.16: Wi Max, Uses a point-to-multipoint topology to provide wireless broadband access
The International Organization for Standards	ISO	OSI model ISO 8877: Officially adopted the RJ connectors ISO 11801: Cabling standard similar to EIA/TIA 568

The Telecommunications Industry Association	TIA	TIA-568-C: Telecommunications cabling standards, used by nearly all voice, video and data networks. TIA-569-B: Commercial Building Standards for Telecommunications Pathways and Spaces TIA-598-C: Fibre optic colour coding TIA-942: Telecommunications Infrastructure Standard for Data Centres
The Electronic Industries Alliance	EIA
International Telecommunications Union-Telecommunications Standardization Sector	ITU-T	G.992: ADSL
The Internet Corporation for Assigned Names and Numbers	ICANN
The Internet Assigned Numbers Authority	IANA
American National Standards Institution	ANSI	568-C: RJ-45pinouts. Co-developed with EIA/TIA