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F Razo / CSUEB TE51105 F Razo / CSUEB TE5110 WORLD WIDE NETWORKS INTERNET NETWORK NODE COMPUTERS IP Communications Protocol FAR OUTSIDE WORLD (WAN, WWW, etc.) Wired or Wireless COMMUNICATIONS SERVER FILE SERVER PRINTER SERVER NEAR OUTSIDE WORLD (LAN) Wired or Wireless TCP/IP Communications Protocol USER COMPUTERS You / Me F Razo / CSUEB TE5110 F Razo / CSUEB TE5110 Local Input Remote Input Keyboard, Mouse, Modem, Touch Screen, Industrial Electro-Magnetic Sensors, etc. Local Output Local and Remote Local Storage Remote Storage Remote Output Visual Electronic CRT, LED, Plasma, Hard Copy Printed, Electrical Control Impulses, etc. Fixed and Removable. Hard, Soft. Magnetic, Optical, Semiconductor. Discs, Tapes, Cards, Sticks, etc. F Razo / CSUEB TE5110 1 2 POWER TO COMPUTER IS TURNED ON ROM BIOS FIRMWARE TRIGGERS AND CHECKS FOR THE PRESENCE AND HEALTH OF VITAL CENTRAL HARDWARE 3 OPERATING SYSTEM (i.e. Windows, Linux, etc.) TRIGGERS AND CHECKS FOR ACCESSORY HARDWARE 4 OPERATING SYSTEM (i.e. Windows, Linux, etc.) INITIATES A CHECK OF CONNECTED NEAR OUTSIDE WORLD (LAN) 5 OPERATING SYSTEM (i.e. Windows, Linux, etc.) INITIATES A CHECK OF FAR OUTSIDE WORLD (WAN, WWW, etc.) F Razo / CSUEB TE5110 THE FAR OUTSIDE WORLD (WAN, WWW, etc.) 5 4 VERY HIGH SPEED,MASSIVE DATA COMMUNICATIONS, WEB MANAGEMENT, SEARCH ENGINE SERVICE COMPUTERS, etc. THE NEAR OUTSIDE WORLD (LAN) LOCAL COMMUNICATIONS SERVER COMPUTER ATTACHED STORAGE SERVER COMPUTER INTERNET & WEB SERVER COMPUTER AREA PRINTER SERVER COMPUTER ACCESSORIES INDIVIDUAL USER COMPUTER Digital CAMERAS EXTERNAL COMMUNICATIONS HARDWARE & SOFTWARE USB Port TELEPHONE Communications Port HIGH SPEED NETWORK Communications Port INFRARED Communications Port 3 SCANNERS USB Port USB PRINTERS USB Port HARD DISC CD Drive 2 BIOS RAM-MEMORY) CENTRAL PROCESSING UNIT DVD Drive FLOPPY Drive 1 VIDEO MONITOR Port BATTERY POWER SUPPLY (INTEL/AMD/APPLE/SUN/etc.) KEYBOARD Port MOUSE Port SPEAKERS Port Miscellaneous PDA, AUDIO, VIDEO & GAME devices MICROPHONE Port LOCAL PRINTER (Parallel) Port SERIAL (RS232) Port F Razo / CSUEB TE5110 F Razo / CSUEB TE5110 - 2005 WAN, INTERNET, FAR REMOTE WWW, etc. INTERNET LOGIN LAN, CORPORATE INTRANETS NEAR REMOTE LAN LOGIN DESKTOP Data Cable, Wireless, Satellite Telephone, Data Cable, Wireless LOCAL THE BROWSER SOFTWARE (i.e. EXPLORER, NETSCAPE) RETRIEVES AND EXCHANGES DATA WITH LOCAL, NEAR-FAR, AND REMOTE WEB SERVERS TO FEED THE CLIENT’S PAGES PC LOGIN F Razo / CSUEB TE5110 - 2005 F Razo / CSUEB TE5110 - 2005 WAN, INTERNET, FAR REMOTE WWW, etc. INTERNET LOGIN Far Client Mailbox e.g. Hotmail Data Cable, Wireless, Satellite Near Client Mailbox e.g. Novell NEAR REMOTE LAN LAN LOGIN LOCAL DESKTOP Telephone, Data Cable, Wireless Local Client Mailbox THE E-MAIL SOFTWARE (i.e. OUTLOOK, EUDORA, or WEB BROWSER) RETRIEVES AND EXCHANGES DATA WITH LOCAL, NEAR-FAR, AND REMOTE MAIL SERVERS TO FEED THE CLIENT’S MAIL SCREENS PC LOGIN F Razo / CSUEB TE5110 - 2005 Computer Network Communications TCP (Transmission Control Protocol) / IP Internet Protocol The Defense Advance Research Projects Agency (DARPA) originally developed the Transmission Control Protocol/Internet Protocol (TCP/IP) to interconnect various defense department computer networks. The International Standards Organization (ISO), and the Institute of Electric and Electronics Engineers (IEEE) also have developed protocols (e.g. X.25, RS232) for the purpose of standardizing computer connections and communications. The Internet is an international Wide Area Network that uses these, and other communications protocols to facilitate interconnection among all kinds of computers using the diverse kinds of data, voice, and video networks seen today. The TCP/IP suite includes the following individual protocols: User Application Higher Logic understandings “Raw wire” understandings REMOTE COMPUTER(S) LOCAL COMPUTER Computer Network Communication Protocols Overview Diagram - TCP (Transmission Control Protocol) & IP Internet Protocol http://www.protocols.com/pbook/tcpip1.htm Description of Components of TCP / IP Computer Communication Protocols Page 1 of 2 Session Layer Data Link Layer ARP/RARP Address Resolution Protocol/Reverse Address BGMP DCAP Data Link Switching Client Access Protocol Diameter Network Layer DHCP Dynamic Host Configuration Protocol DVMRP Distance Vector Multicast Routing Protocol ICMP/ICMPv6 Internet Control Message Protocol IGMP Internet Group Management Protocol IP Internet Protocol version 4 IPv6 Internet Protocol version 6 MARS Multicast Address Resolution Server PIM Protocol Independent Multicast-Sparse Mode (PIMSM) RIP2 Routing Information Protocol RIPng for IPv6 Routing Information Protocol for IPv6 RSVP Resource ReSerVation setup Protocol VRRP Virtual Router Redundancy Protocol Transport Layer ISTP Mobile IP Mobile IP Protocol RUDP Reliable UDP TALI Transport Adapter Layer Interface TCP Transmission Control Protocol UDP User Datagram Protocol Van Jacobson compressed TCP XOT X.25 over TCP Border Gateway Multicast Protocol DIS Distributed Interactive Simulation DNS Domain Name Service ISAKMP/IKE Internet Security Association and Key Management Protocol and Internet Key Exchange Protocol iSCSI Small Computer Systems Interface LDAP Lightweight Directory Access Protocol MZAP Multicast-Scope Zone Announcement Protocol NetBIOS/IP NetBIOS/IP for TCP/IP Environment Application Layer COPS Common Open Policy Service FANP Flow Attribute Notification Protocol Finger User Information Protocol FTP File Transfer Protocol HTTP Hypertext Transfer Protocol IMAP4 Internet Message Access Protocol rev 4 IMPPpre/IMPPmes Instant Messaging and Presence Protocols IPDC IP Device Control IRC ·Internet Relay Chat Protocol ISAKMP Internet Message Access Protocol version 4rev1 ISP NTP Network Time Protocol POP3 Post Office Protocol version 3 Radius Remote Authentication Dial In User Service RLOGIN Remote Login Description of Components of TCP / IP Computer Communication Protocols Page 2 of 2 Tunneling Session Layer (continued) RTSP Real-time Streaming Protocol ATMP Ascend Tunnel Management Protocol SCTP Stream Control Transmision Protocol L2F The Layer 2 Forwarding Protocol S-HTTP Secure Hypertext Transfer Protocol L2TP Layer 2 Tunneling Protocol SLP Service Location Protocol PPTP Point to Point Tunneling Protocol SMTP Simple Mail Transfer Protocol SNMP Simple Network Management Protocol AH Authentication Header SOCKS Socket Secure (Server) ESP Encapsulating Security Payload TACACS+ Terminal Access Controller Access Control System TLS Transport Layer Security Protocol TELNET TCP/IP Terminal Emulation Protocol TFTP Trivial File Transfer Protocol WCCP Web Cache Coordination Protocol X-Window X Window Routing BGP-4 Border Gateway Protocol EGP Exterior Gateway Protocol EIGRP Enhanced Interior Gateway Routing Protocol HSRP Cisco Hot Standby Router Protocol IGRP Interior Gateway Routing NARP NBMA Address Resolution Protocol NHRP Next Hop Resolution Protocol OSPF Open Shortest Path First TRIP Telephony Routing over IP Security F Razo / CSUEB TE5110 - 2005 Computer Operating System - Multitasking The Operating System (OS) of the computer is a program that coordinates the computing tasks in the machine, keeping track of who is using the (single or multiple) processor, storage, and communications resources. The MS Windows and Apple OS X, as well as the UNIX (and LINUX) operating systems all do the same, their own way. The window below pops up under MS Windows, by pressing ONCE the ALT-CTRL-DEL keys simultaneously, and shows a list of user application programs running and sharing resources in a computer. Which programs are currently running on this computer? Computer Operating System Multiprocessing The Operating Systems normally breaks down major tasks in multiple processing routines. Operating systems coordinate the input, processing, storage, and output needs of the multiple tasks being served. The list on the right shows processes running on an MS Windows machine, and include user tasks, as well as many of the housekeeping tasks involved in running the operating system itself. In the case shown, which routine is “using” about 97% of the CPU processing capacity? When one of the processes becomes tangled up, or “bogged down”, executing repeatedly the same thing, or waiting hopelessly because of faulty program logic, computer resource deficiencies, or bad administration, the computer can become unreasonably slow, and perhaps even “frozen”: What can we do then? Computer Operating System – Performance Monitoring Present Operating Systems also can provide a program that displays graphically the level of activity and utilization of various computer resources. The window shown on the right shows a graph of: a) the percent utilization of the computer central processing unit (CPU). What percent of the CPU capacity is typically free? b) the number of times, or pages the CPU has had to off-load data from the fast (DIM-chip) RAMMEMORY areas, to the more permanent, massive, slower, HARD magnetic DISC (VIRTUAL memory) for functionality purposes. About how much hard disc memory (MB) is being used for fast-memory pages? A large number of page swapping to hard disc can be an indication of under-capacity in the available fast RAM-MEMORY space, which can cause a slower, sluggish machine operation. What can be done then? Computer Operating System – Hard Disc Utilization The window on the right shows the window “My Computer” of an MS Windows operating system. This window lists all the storage devices available to the user, and key utilization “Details” figures for the selected (highlighted) device. In the screen shown, the Local Hard Disc (C:) shows using an NTFS (!) method of linking files, a “Total Size” of 37.2 Giga Bytes (GB, thousand million bytes of data), and an amount of 22.4 Giga Bytes of “Free Space”. In a typical system, and depending of its use (NOTE: digital pictures, music and video use LOTS of bytes!), an amount of Free Space less than 1 Giga Byte could soon be insufficient for all the tasks needing it (Windows itself needs about 200 Mega Bytes, or two-tenths of a Giga Byte). When hard disc space is insufficient, a machine will struggle and become slow in its effort to shuffle and allocate needed space. In a personal computer, this problem, which is called disc “trashing” can often be seen and heard. How does the machine shown here looks? If a computer has an amount of hard disc Free Space of say, 100 Mega Bytes (one-tenth of a Giga Byte), and appears to be sluggish and trashing, What could be possible solutions? Computer Operating System – Network Performance Monitoring The window on the right shows the utilization of networking resources in a computer. The computer that produced the image was not connected to a Local Area Network, therefore its utilization stays at 0%. If a computer shows very high utilization percentages for networking resources, say above 80% during start-up, and it is slow and sluggish to begin, What could be the problem?