Lecture 1. TCP/IP Overview and History презентация

the predecessor of the Internet.
Packet-switching mode and redundant topology.
Concepts: communication, internetwork, internet, intranet, Internet, and other concepts.
Protocol, stack of protocols, protocol suite.
TCP/IP architectural model.

Semester – 7-th
Lectures – 2 academic hours per a week
Laboratory classes – 2 academic hours per a week
Modules – 2
Course Project – 1
Exam

Computer networks let you make more mistakes faster than any invention in human history – with the possible exceptions of handguns and tequila.

Ethernet and Token Ring need to be connected together, this requires reconstruction of the data frames. To do this, a special intermediary device called a gateway is used.
A gateway is a device that can connect a LAN to a LAN, a LAN to a WAN, a LAN to a mainframe, translate protocols, or convert transmission media.
In the general case a gateway can require information from above the application layer of the OSI model. In TCP/IP networks gateways require information from three bottom layers.

Interconnection is the physical linking of different networks with each other by means of a special equipment and physical media of the data transmission.
Gateway – шлюз.

The Ethernet network was first deployed in 1976.
The Token Ring LAN was introduced by IBM in 1984 and was then standardized with protocol IEEE 802.5.
The ARCNet (Attached Resource Computer Network) was invented in 1976 and was first put into service at Chase Manhattan Bank in 1977.

role in launching the Information Revolution. The agency developed and furthered much of the conceptual basis for the ARPANET — prototypical communications network launched nearly half a century ago — and invented the digital network protocols that gave birth to the Internet.

Agency overview (by 2009)

Formed - 1958
Since 1972 - DARPA
Headquarters - Arlington, Virginia
Employees - 240
Annual budget - $3.2 billion
Agency executive - Regina E.
Dugan , Director
Website - www.darpa.mil

At first DARPA was created as the Advanced Research Projects Agency (ARPA), by Public Law 85-325 and Department of Defense Directive 5105.41, in February 1958 in response to the surprise Sputnik launch by the Soviet Union in 1957.

The Defense Advanced Research Projects Agency (DARPA) is an agency of the United States Department of Defense responsible for the development of new technology for use by the military.

DARPA has been responsible for funding the development of many technologies which have had a major effect on the world, including computer networking.

in 1962 under the direction of Joseph Licklider to support research dealing with the field of computer related technologies. For 25 years IPTO was responsible for DARPA’s information technology programs.
IPTO did not perform research individually, but rather invested in breakthrough technologies and seminal (продуктивних) research projects that led to significant developments in computer hardware and software.

Some of the most fundamental advances came in the areas of networking, communications, computer graphics, advanced microprocessor design, parallel processing and artificial intelligence. IPTO was conducting an investment strategy in line with the vision of the office’s first director, J. C. R. Licklider.
Licklider believed that humans one day would interact closely with computers, which, in his words, can be gateways to a vast world of online information.
Licklider was a brilliant visionary (блискучим провидцем) and pioneer in the field of human-computer interaction and specifically in the field of interactive computing.

http://www.livinginternet.com/i/ii_ipto.htm

office – міська і міжміська телефонна станції)

б) the distributed switching system, proposed by Paul Baran from RAND corporation

The redundant topology and the packet switching mode of data transmission were the first progressive features of the new network design.

speak the same language which would facilitate communication between them. Each host computer (mainframe) would only have to adapt its language once in communicating with its small computer. Each mainframe would be connected to the network via its small computer which would act as a sort of gateway into networks.

Wesley Clark suggested to employ small computers at each site to perform networking functions and leave the mainframes alone.

Larry Roberts adopted Clark's idea. He called the small computers the Interface Message Processors (IMPs). Roberts decided that the network should start out with four sites: UCLA, the Stanford Research Institute (SRI), the University of Utah, and UC Santa Barbara. This would be the core and the network could grow from there.

- Interface Message Processor is the core component of the network.
The IMP was built on the modified Honeywell DDP-316 minicomputer with 12K 16-bit words of core memory. It provided data transmission between dissimilar computers (mainframes) that resided on the different universities.
The IMPs were interconnected by 56-kbps lines leased from telephone companies.

Science Department became the fourth node on the ARPANET

In August 1969, the first IMP had been delivered to UCLA. A month later, the second IMP had been delivered to SRI. The two IMP were connected by means of 56-kbps lines leased from telephone companies and the ARAPNET was born.

ARPANET was the internetwork that became the basis for the Internet.

Network Measurement Center, with an SDS Sigma 7. It was the first computer attached to the IMP;
2. At the Stanford Research Institute the SDS 940 computer was used.
3. The University of California, Santa Barbara (UCSB) possessed IBM 360/75, running OS/MVT;

4. The University of Utah's Computer Science Department used a DEC PDP-10 operating on TENEX.
The Interface Message Processor (IMP) was the packet switching node used to interconnect different computers to the ARPANET from the late 1960s to 1989. It was the first generation of gateways, which are known today as routers.
An IMP was a ruggedized Honeywell DDP-516 minicomputer with special-purpose interfaces and software.
ARPAnet was closed in early 1990s.

had about 100 nodes. But that was enough to support an online community

http://www.vox.com/a/internet-maps

Licklider - American computer scientist who created the idea of a universal network which his successors developed into the internet, the first Director of the IPTO. He was a brilliant visionary and pioneer in the field of human-computer interaction and specifically the field of interactive computing.
Larry Roberts is sometimes called the "father of the ARPANET.“ He was also the principal architect of the ARAPNET.
Paul Baran had proposed two ideas that became very important in the development of the ARPANET: the first - to build a distributed network; the second - to use a packet switching for data transmitting.
Leonard Kleinrock is an American engineer and computer scientist, a professor at UCLA's Henry Samueli School of Engineering and Applied Science. He made several important contributions to the field of networking, in particular to the theoretical foundations of computer networking. He played an influential role in the development of the ARPANet.

Larry Roberts
( was born in 1937)

https://www.ibiblio.org/pioneers/roberts.html

Paul Baran
(was born in 1926)

Wesley Clark
(was born in 1927) 

Leonard Kleinrock
(was born in 1934)

technologies to deliver data across network connections of any complexity.
The packet switching method of data delivery is used by Ethernet networks and TCP/IP networks.
Router is a basic component of the packet switching networks.

devices: end devices and intermediary devices; medium and services.
End devices are servers and workstations that communicate with people.
Intermediary devices are routers, switches and other communication devices
Devices and medium are the physical elements or hardware of the network.
Services and processes are the communication programs, called software, that run on the network devices.

communicate with each other. Also these devices serve requests generated by people.
Some examples of end devices are:
Computers (work stations, laptops, file servers, web servers);
Network printers;
VoIP phones;
Security cameras;
Mobile handheld devices (such as wireless barcode (штрих-код) scanners, PDAs).

In the context of IP and TCP protocols, end devices are referred to as hosts.

switches, and wireless access points);
Internetworking Devices (routers);
Communication Servers and Modems;
Security Devices (firewalls).

network devices perform such functions:
the regeneration and retransmission of data signals;
the maintaining information about what routes exist through the network and internetwork;
the notification of other devices about errors and communication failures;
sending data along alternate routes when there is a link failure;
classifying and sending messages according to QoS priorities;
the permission or denying the data flow based on security settings.

Intermediate – проміжний, перехідний, проміжний ланцюг, посередник
Intermediary – посередник, посередництво, проміжний

cables (twisted pair and coaxial cables);
glass or plastic fibres (fibre optic cable);
radio waves for wireless transmission.

Criteria for choosing a network media are:
The distance the media can successfully carry a signal.
The environment in which the media is to be installed.
The amount of data and the speed at which data must be transmitted.
The cost of the media and their installation.

information between two or more network entities, for example, end devices.
A communications is a system for transmitting information, for example, computer network, telephone, TV and so on.
In the world of computer networks, networking is the practice of interfacing two or more network computing devices (end devices) with each other for the purpose of data exchanging.
Internetworking is the interconnection of two or more networks via special means and technologies.
An internetwork (or internet) is a group of networks connected by routers for communication purposes. Hence, an internetwork might be a heterogeneous network. Inherently, the words internetwork and internet are simply a contraction of the phrase interconnected networks.
The Internet is a publicly accessible system of networks that connects computers around the world via the TCP/IP protocols.
The intranet is a connection of private LANs and WANs that belongs to an organization or enterprises.
"to interconnect" is equal to "to connect with one other".

widely used publicly-accessible internetwork that was created by means of TCP/IP protocols.

LANs and WANs may be interconnected into an internetwork - a global mesh of interconnected computer networks.

standard procedure for regulating data transmission between network computers (network devices).
A protocol is a set of rules governing the transmission process of messages and their format which computers can exchange on the network.
IP (Internet Protocol) is the sample of computer network protocols.

A standard is a protocol (official document) that has been endorsed (схвалений) by the networking industry and ratified by a standards organization, such as:
the Institute of Electrical and Electronics Engineers (IEEE) or
the Internet Engineering Task Force (IETF).
Many of the networking protocols refer to other widely utilized protocols or industry standards.
The use of standards in developing and implementing computer networks ensures that products from different manufacturers can work together for efficient communication.

network protocols. 
All these protocols work together and perform a complex of interrelated networking tasks.
All protocols of a stack are divided into layers.

A protocol suite (комплект) is a group of interrelated network protocols that are necessary to perform communication functions on a network.
A protocol stack is a complete set of interrelated network protocols that are divided into layers and work together to provide networking capabilities.

data unit);
the method 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.

TCP/IP protocol stack.
TCP and IP are two main protocols of the TCP/IP protocol stack.
This model is known by different names:
the TCP/IP architectural model;
the DARPA model (after the Defense Advanced Research Projects Agency - agency that was largely responsible for developing TCP/IP);
the DoD model (after the United States Department of Defence).

consists of these steps:
Creation of data at the application layer of the originating source device (end device);
Segmentation and encapsulation of data as it passes down the protocol stack in the source device (end device);
Generation of the signal onto the medium at the network access layer of the stack (in fact, by means of a equipment of the OSI Physical layer);
Transportation blocks of the data through the internetwork, which consists of medium and an intermediate devices;
Reception of the data at the network access layer of the destination (end device);
Decapsulation and reassembly of the data as it passes up the stack in the destination device;
Transfer this data to the destination application at the Application layer of the destination end device.

blocks of information that are created at each level of the reference model.

role and purposes of ARPA.
Tell about a role and purposes of IPTO.
Describe the scheme of the ARPA Network.
What does the IMP stand for? What are the functions of IMP?
What topology is called redundant? Why is redundant topology used for large regional networks?
Explain the packet-switching mode?
Tell about an initial configuration of the ARPANet?
Name the main end network devices and explain briefly their role and designation.
Name the main intermediary network devices and explain briefly their role and designation.
What does the term ‘protocol’ mean in computer networking?
Describe the TCP/IP architectural model.