Network Evolution
Continuously evolving for more than 30 years
Provides companies with the ability to share data between systems
Database
Web
History
Required “sneakernet” to share data
Host computing (centralized)
Mainframe from single vendor
User terminals were not intelligent
Relied on centralized host for all capabilities
IBM, Digital, etc.
Types
Local Area Networks (LAN)
PC-based
Sometimes known as Intranet
Used within a single facility (campus) to share data between PC systems
Novell Netware, Microsoft Windows networking
Metropolitan Area Networks (MAN)
Several LAN that cover a larger area or connect a few campus networks together
Usually within the same city and use a short-range connectivity solutions
Microware or laser
Wide Area Network (WAN)
Network spread over a very large geographical area
Uses technologies which allow longer distance to be obtained
Phone service or satellite
Enterprise
Extranet or Virtual Private Network (VPN)
Utilizes public medium, such as the Internet, to connect external devices to an Intranet
VPN – Remote access employees
Extranet – Partner or affiliate companies
Storage Are Network (SAN)
Supports disk mirroring, backup and restore, archival and retrieval of archived data, data igration, and sharing of data among different network servers in a network
Content Delivery Network
Service of copying pages of Web site to geographically disperse servers
Dynamically identifies and serves page content from the closest server to the user, enabling faster delivery
Typically, high-traffic website owners and Internet Service Providers (ISPs) hire services of companies that provide content delivery
Internetworking
The process of interconnecting two or more individual networks to facilitate communications among their respective parts
may be of different types, each having its address, internal protocols, access methods, and administration
The focus is the ability to communicate dissimilar media types
No one solution right for everyone
Must provide
Reliable communication
Scalability / expandability
Manageability
Security
TCP/IP Connectivity
In 1969 – Department of Defense commissioned Advanced Research Projects Agency (ARPA) networks
ARPANET used Network Connection Protocol (NCP)
TCP/IP research began
Stanford University
Funding by Department of Defense
Developed a four layer networking model
Research published in Request for Comments (RFCs)
Internetworking, as we know it, was born
De facto standard
OSI Model
1970 – International Organization of Standardization (ISO) began work seven-layer model
Open Systems Interconnection (OSI) was born
Created a full standard set for all internetworking communications
1979 OSI completed
Creation of the Distribution Processing model
LAN and WAN definitions were born
Ethernet
1970s – Digital, Intel, and Xerox (DIX) consortium created the original Ethernet
Ethernet II standard was subsequently defined and released
Known as ARPA Ethernet
802.x
1980 – Institute of Electrical and Electronic Engineers, Inc. (IEEE) to on Project 802
802.2 – Logical Link Control (LLC) focus on end-to-end link connectivity and the interface between the higher layers and the medium-access-dependent layers
802.3 – Became the Ethernet standard (pushed by DIX)
802.4 – Token Bus
802.5 – Token Ring (pushed by IBM)
Requirements for Network connection
Physical connection
Logical connection
protocols
Applications
interpret the data and display the information
How network send data?
Packets are basic units for network communication
Send the original, disassembled data in small chunks.
Reassemble the data in the proper order when it reaches its destination.
Check the data for errors after it has been reassembled.
Network Devices
Equipments that connect directly to a network segment
Two Classifications of Network Devices
End-User devices
Network devices
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