3. Netwrok [Communication]
3
1. Message: The message is the information (data) to be
communicated. Popular forms of information include text,
numbers, pictures, audio and video.
2. Sender: The sender is the device that sends the data message. It
can be a computer, workstations, telephone handset, video
camera and so on.
4. Netwrok [Communication]
4
3. Receiver: The receiver is the device that receives the message. It
can be a computer, workstations, telephone handset, television
and son on.
4. Transmission medium: The transmission medium is the physical
path by which a message travels from sender to receiver. Some
examples of transmission media include twisted-pair wire,
coaxial cable, fiber-optic cable, and radio waves.
5. Netwrok [Communication]
5
5. Protocol: A protocol is a set of rules that govern data
communications. It represents an agreement between the
communicating devices. Without a protocol, two devices may be
connected but not communicating, just as a person speaking
French cannot be understood by a person who speaks only
Japanese.
13. Model- [OSI] → Data link Layer
13
→ Hop to Hop(node to node) delivery by the data link layer.
• Data-unit [frames]
• Physical addressing
• Flow control [Fast,Slow]
• Error control
• Access control[Shared Channel]
19. Model- [OSI] → Session Layer
19
• Host Layers
• Data-unit [data]
• Dialog contro [keeping track of whose turn it is to transmit]
• Token management [preventing two parties from attempting the
same critical operation at the same time]
• Synchronization
27. • connectionless and connection-oriented
communication in the network layer
• connection-oriented communication in
the transport layer
• Connectionless communication in the
network layer
• connectionless and connection-oriented
communication in the transport layer
Model- [Compare OSI vs TCP/IP]
27
OSI TCP/IP
• Service
• Interface
• Protocol
• The TCP/IP model did not originally clearly
distinguish between service, interface, and
protocol,
• The OSI reference model was devised
before the corresponding protocols
were invented.
• TCP/IP the reverse was true
• OSI model has seven layers • TCP/IP has four layers
28. Model- [TCP/IP]-Protocol
28
TCP/IP Layer Protocol
Application Layer
HTTP FTP Telnet SMTP DNS
Transport Layer UDP TCP
Netwrok Layer IP ARP ICMP IGMP
Access Network
[Host to Netwrok] Token Ring Enternet
29. [TCP/IP]-[Application layer]-Protocol
29
1. HTTP [HyperText Transfer Protocol]
HTTP is the underlying protocol used by the World
Wide Web and this protocol defines how messages are
formatted and transmitted, and what actions Web
servers and browsers should take in response to
various commands.
• HTTP is connectionless.
• HTTP uses a client-server architecture.
30. [TCP/IP]-[Application layer]-Protocol
30
2. FTP [File Transfer Protocol]
FTP is the commonly used protocol for exchanging files
over the Internet. FTP uses the Internet's TCP/IP protocols
to enable data transfer.
• FTP is connection-oriented.
• FTP uses a client-server architecture.
33. [TCP/IP]-[Application layer]-Protocol
33
5. DNS [Domain Name System]
The (DNS) is the phonebook of the Internet. Humans access
information online through domain names, like google.com or
youtube.com. Web browsers interact through Internet Protocol (IP)
addresses. DNS translates domain names to IP addresses so browsers
can load Internet resources
35. [TCP/IP]-[Transport layer]-Protocol
35
1. TCP [Transmission Control Protocol]
• Transmission Control Protocol is a connection-oriented protocol.
• Acknowledgement segments
• The speed for TCP is slower than UDP.
• HTTP, HTTPs, FTP, SMTP, Telnet
2. UDP [User Datagram Protocol]
• User Datagram Protocol is a connectionless protocol.
• No Acknowledgment,
• UDP is faster because error recovery is not attempted. It is a "best effort" protocol.
• DNS, DHCP, TFTP, SNMP, RIP, VOIP.
36. [TCP/IP]-[Network layer]-Protocol
36
1. IP[Internet Protocol]
An Internet Protocol address (IP address) is a
numerical label assigned to each device connected to
a computer network that uses the Internet Protocol
for communication.
38. [TCP/IP]-[Network layer]-Protocol
38
3. ICMP(Internet Control Message Protocol)
ICMP is an error reporting protocol and is an extension to the
Internet Protocol (IP).
4. IGMP(Internet Group Management Protocol )
The IGMP is a communications protocol used by hosts and adjacent
routers on IPv4 networks to establish multicast group memberships.
IGMP is an integral part of IP multicast
40. [Addressing]→ Physical
40
A physical address is the hardware-level address used by the
Ethernet interface to communicate on the network. Every device
must have a unique physical address.
This is often referred to as its MAC (Media Access Control)
address.
[ 08:56:27:6f:2b:9c ]
Card ID
Vendor ID
41. [Addressing]→ Logical
41
A logical address is a network-layer address that is interpreted by a
protocol handler.
Logical addresses are used by networking software to allow packets
to be independent of the physical connection of the network, that
is, to work with different network topologies and types of media.
Each type of protocol has a different kind of logical address.
167 : 21 : 34 : 5
FDEC : BA98 ::: ADFC : BDFF : 2990 : FFFF
42. [Addressing]→ Logical
42
Note that although physical addresses will change from hop to hop,
logical addresses remain the same from the source to destination.
![Netwrok [Communication]
2
A data communications system has five components.](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)