What Is an Internetwork?
An internetwork is a collection of individual networks, connected by intermediate networking devices, that functions as a single large network. Internetworking refers to the industry, products, and procedures that meet the challenge of creating and administering internetworks.
History of Internetworking
The first networks were time-sharing networks that used mainframes and attached terminals. Such environments were implemented by both IBM's Systems Network Architecture (SNA) and Digital's network architecture. Local-area networks (LANs) evolved around the PC revolution. LANs enabled multiple users in a relatively small geographical area to exchange files and messages, as well as access shared resources such as file servers and printers. Wide-area networks (WANs) interconnect LANs with geographically dispersed users to create connectivity. Today, high-speed LANs and switched internetworks are becoming widely used, largely because they operate at very high speeds and support such high-bandwidth applications as multimedia and videoconferencing. This lack of network management meant that no centralized method of managing and troubleshooting networks existed. Connectionless Internetworking
No unnecessary overhead
Not guaranteed delivery
Not guaranteed order of delivery
Packets can take different routes
Reliability is responsibility of next layer up (e.g. TCP)
Areas of connectivity
Implementing a functional internetwork is no simple task. Many challenges must be faced, especially in the areas of connectivity, reliability, network management, and flexibility. The challenge when connecting various systems is to support communication among variety of technologies. Different sites, for example, may use different types of media operating at varying speeds, or may even include different types of systems that need to communicate.
The Internet Protocol (IP)
A standard format in which to send data packets to the network The most popular protocol in the world (almost exclusively used in all networks) Other similar protocols have almost completely disappeared (AppleTalk, IPX, ..) Standardized in RFC791 (September 1981)
Currently used: IPv4
Next version: IPv6
The IP address
The “IP address” is found in the fourth and fifth 32-bit fields of the IPv4 packet => An IP address is a 32-bit integer
Uniquely identifies the sender and recipient of the data packet If IP address is an integer, then what is this: 192.168.1.2? What is the maximum number of unique IPv4 addresses?
The successor of IPv4 (there is no IPv5)
An IPv6 is address is 128 bits (vs. IPv4 address being 32 bits) Usually expressed as a string of 8 groups representing 16 bits each, delimited by a colon: 2001:0db8:0000:0000:0000:ff00:0042:8239
Can also be shortened as: 2001:db8::ff00:42:8239
Somewhat supported in most software / operating systems / networking applications. Not very widely used in production at this time.
How many unique addresses in IPv6?
Unique IPv6 addresses
000,000,000 (2^128 =~ 3.4 x 10^38)
What is your IP address?
Find your IP address on the command line:
“ipconfig” on Windows
“ifconfig” on Linux, OS X or other Unix-like systems
Find your IP address as it is seen to the world:
Is there a difference? Can you explain the difference?
Open System Interconnection Reference Model
The Open System Interconnection (OSI) reference model describes how information from a software application in one computer moves through a network medium to a software application in another computer The OSI reference model is a conceptual model composed of seven layers, each specifying particular network functions. Internetwork Addressing
Inter network addresses identify devices separately...
Please join StudyMode to read the full document