Presentation on theme: "Managing A Network. Managing Why? Who – Network Manager / Network Administrator Credentials –MSCE, CNE –Sun Certified System Administrator Solaris –Sun."— Presentation transcript:
Managing A Network
Managing Why? Who – Network Manager / Network Administrator Credentials –MSCE, CNE –Sun Certified System Administrator Solaris –Sun Certified Network Administrator Solaris
Managing Systems –Clients, Servers, Network Hubs, Routers, Remote Access Devices, Printers, etc. –Users –Interfacing with other organizations –Audits, backups –Software updates
Server Managing Hardware Issues –CPU Power & Number –Memory –Hard Disks, size, type, storage architecture SCSI, IDE Striping, Mirroring, Raid
Managing Servers Busy disks or printers store information in queues, (memory or disk space) Disks use an area know as swap space as if it were memory, when memory gets filled. –Free disk space is critical to good performance Fragmentation is another concern
Managing Servers Drives need to be defragmented routinely Drives need to be scanned for bad sectors as numerous writes and re-writes damage the media.
Managing Servers Memory –Memory gets sub-divided into page frames –Programs and information are loaded as needed Paging Look ahead capability Page fault occurs when the machine can’t load the next program piece into memory –Order more memory
Managing Servers Stored data errors –Disks wear out –Maximize redundancy against cost Redundancy Fault tolerance – back-up mechanisms –Trade offs against budget
Data storage models Mirroring ( Shadowing) –Two disk exactly the same. Hardware & software mirroring One controller – two drives –Duplexing Town controllers, two drives
Data storage models Raid –Redundant array of inexpensive (independent) disks ( Hardware or software) –Involves disk striping –Raid levels 0 thru 5 –The RAID appears as one logical disk RAID –1 is a disk mirror
Data storage models Raid –RAID – 5 has at least three disks The more spindles, the smaller the impact on disk space Data is written across all the disks, including parity If a disk fails, the parity is used to restore the data when a new disk is installed –See -
Raid 0 RAID Level 0 requires a minimum of 2 drives to implement
Raid 0 Characteristics/Advantages RAID 0 implements a striped disk array, the data is broken down into blocks and each block is written to a separate disk drive I/O performance is greatly improved by spreading the I/O load across many channels and drives Best performance is achieved when data is striped across multiple controllers with only one drive per controller Disadvantages Not a "True" RAID because it is NOT fault-tolerant The failure of just one drive will result in all data in an array being lost Should never be used in mission critical environments
Raid 0 Advantages Cont. No parity calculation overhead is involved Very simple design Easy to implement Recommended Applications Video Production and Editing Image Editing Pre-Press Applications Any application requiring high bandwidth
Tape Drives Historically proven to confuse people –too many standards across manufacturers Cheaper for mass storage of data QIC Standard (Quarter inch Cartridge) –60 megs / 9 data tracks / 300 ft. of tape –cartridge was too big
Tape Drives Second Standard (cassette) Lead to DC (large cartridge) –MC (small Cartridge) Better the controller / faster the backup QIC-40 FAT 20 Tracks 68 segments of 29 sectors
Tape Drives DAT (Digital Audio Tape) –helical scan technology digital formatting high capacity / reliability 8mm –high throughput DLT (Digital Linear Tape) –20 to 40 G M/sec
Tape Drives TRAVAN (3M) –proprietary, levels TR-1 through TR-4 –400 meg uncompressed TR-1 –800 meg uncompressed TR-2 –1.6G uncompressed TR-3 –4G uncompressed TR-4 –All drives feature 2 to 1 compression
Tape Drives Which one? –Amount of data –Data throughput required –best for you standard –cost $$$
Backups Transferring data from a hard drive to another medium –CD, Tape, Disk Full Backup –Image –File – file
Backups Incremental –Copy the files that have changed since the last backup. Differential –Files that changed since the last full b/u Daily –Copy files that changed on a particular day
Other Storage Devices Jazz Drives Zip Drives LS-120 drive Magneto-Optical WORM drives
Network Performance SNMP- Simple Network Management Protocol –Part of TCP/IP –Stores information in MIB, management information base –Collected using software agents –Monitored by a SNMP management station CMIP – Common Management Interface Protocol –Higher memory requirements –Part of OSI model
Tools Multi Meter –Voltmeter –Ohm Meter Cable scanner –Optical Fault Finder –Time domain reflecometer (TDR) Protocol Analyzer
Vulnerabilities Personal computer Network Mainframe Files & Programs
Vulnerabilities Privacy People Building Equipment
Trends that create vulnerabilities: Networking systems are proliferating, radically changing the installed base of computer systems and system applications. Computers are an integral part of American Business, computer related risks cannot be separated from general business risks.
Trends The widespread use of databases containing personal information, i.e. medical or credit records, places individual privacy at risk. Computers are placed in areas that demand a high degree of trust, (i.e. medical instruments) increases the likelihood that accidents can result in death.
The ability to abuse computer systems is widespread. The International political environment is unstable, raising questions about the potential for transnational attacks as computer networks are growing. Computers are in demand and easily stolen.
Security Security implementation depends upon - –Value of the information protected. –Function the system performs –Cost vs. Benefit –Nature of the organization
The Nature of Security Vulnerability Threat Countermeasure Security must be holistic - Technology, Management, and Social Elements
Consists of - Computer hardware, software, network, facilities, and people Safety and Security go hand in hand Physical Security - protecting the building and the personnel within the building. –Use access control - –Cipher locks, fences, guards, TV monitoring
Consists of - Program Security - ensuring that computer programs are not tampered with and the physical code is reliable. Use frequent audits, local administrator, configuration control Make use of accounting programs
Computer security More information is available to more people. the lack of control over information increases the opportunity for harm. Technology is advancing at a rate that out paces the legal system.
Authorization vs. Access - Ensuring that those that use the programs are in fact authorized to perform the function. Password control, access control Network Security - monitoring the computer network for unusual occurrences. Network management software
Site Security - Ensuring that the computer location is protected and that in the event of a disaster the software & hardware are protected. Off sight storage of software and files Alternate sight if primary sight is damaged
Personnel Security - Monitoring the employees within an organization. Codes of Conduct, Security clearances, Background checks, network software to Watch for unusual activity, two-person control