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Tables & Charts

Network topologies

Topology Description Advantage Disadvantage

Star All nodes connect to a singlecentral device

Inexpensive & easy If hub fails, network down; maximumnodes = 1024

BusAll nodes connect to acommon backbone

Simple & less cablesIf backbone fails, network down; both endsmust be terminated

RingEach node is connected to twoother device

No collisions; less signaldegeneration

Expensive; difficult to troubleshoot;proprietary hardware

MeshEach node connects to everyother device

Redundancy & faulttolerance

Expensive; complicated; difficult totroubleshoot

Common networking standards

Standard Description SpeedAccessMethod

Topology Media

802.3 Ethernet10, 100, 1000Mbps

CSMA/CDphysical star, logicalbus

UTP, STP, fiberoptics

802.5 Token ring 4, 16 Mbps Token passingphysical star, logicalring

STP

802.11 Wireless networks 1, 11, 54 Mbps CSMA/CA cellular Atmosphere

FDDIFiber Distributed DataInterface

100 Mbps Token passing dual ring Fiber optics

Ethernet specifications

Designation Cable Type Max Length Speed Connector Topology Standard

10BASE-T Cat3 UTP 100 m 10 Mbps RJ45 star IEEE 802.3i

10BASE-FL MMF 2000 m 10 Mbps ST star IEEE 802.3j

100BASE-TXCat5 UTP, Cat5eFTP

100 m 100 Mbps RJ45 starIEEE802.3u

100BASE-FX Micro MMF

412 m (halfduplex)

2000 m (fullduplex)

100 Mbps (halfduplex)

200 Mbps (fullduplex)

SC

star, point-

point

IEEE

802.3u

1000BASE-TCat5e / Cat6 UTP(4 pairs)

100 m 1 Gbps RJ45 starIEEE802.3ab

1000BASE-CX

Twinax STP 25 m 1 Gbps HSSDCstar, point-point

IEEE802.3z

1000BASE-SX

Micro MMF550 m (50u)275 m (62.5u)

1 Gbps SC point-pointIEEE802.3z

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1000BASE-LX

SMF or MMF550 m (MMF)5000 m (SMF)

1 Gbps SC, LC point-pointIEEE802.3z

10 GBASE-SR

MMF 300 m 10 Gbps850nm serialLAN

point-pointIEEE802.3ae

10 GBASE-

LR

MMF 10,000 m 10 Gbps1310nm serial

LAN

point-pointIEEE

802.3ae10 GBASE-ER

MMF 40,000 m 10 Gbps1550nm serialLAN

point-pointIEEE802.3ae

Wireless networking technologies

Standard Data Speed Frequency Transmission Type Topology Range

IEEE 802.11Legacy

2 Mbps 2.4 GHz FHSS or DSSS Point-point 30 m

IEEE 802.11b

WiFi 11 Mbps 2.4 GHz DSSS with CCK Point-point 30 m

IEEE 802.11aWiFi

54 Mbps 5 GHz OFDM Point-point 30 m

IEEE 802.11gWiFi

54 Mbps 2.4 GHz>20 Mbps: OFDM,

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2 Data Linkencoding/decoding of packets intobits; frame synchronization, errorchecking

framesMAC, LLC, PPP, ATM, framerelay, 802.11b/g, L2TP, FDDI

switch,bridge

1 Physicalelectrical, mechanical, lightwave,radio frequency, mediaspecifications

bitsEthernet, WiFi, Token Ring, BRI,RS232, V.35

hub, NIC,WAP

Physical media types

Medium Description Types Remarks

Twisted pairConsists of multiple insulated wires that aretwisted together in pairs to prevent crosstalk

UTP, STP,ScTP

Cat3(16MHz), Cat5(100MHz),Cat5e(100MHz), Cat6(250MHz)

Coaxialcable

Consists of a center conductor surrounded by aplastic jacket with braided shield

75, 50RG-58 (thinnet), RG-8(thicknet), RG-62(ARCnet)

Fiber optic

cable

Consists of a center glass core surrounded by

glass cladding and other protective materials

SMF ,

MMF

8~10um(SMF), 50~62.5um(MMF),

125um(clad), EMI immune

Types of media connectors

Connector DescriptionLock

MethodUsage Developed by

RJ11Registered Jack modularconnector (6P2C)

snap-in telephone equipments, PBX Bell Telephone Labs

RJ45Registered Jack modularconnector (8P8C)

snap-intwisted pair ethernet, PoE,ISDN, T1, token ring

Bell Telephone Labs

F-typeF-type coaxial connector(75)

screw-onbroadband cable, CATV,CCTV

BNC Bayonet Nut Coupling (50) bayonetthin ethernet, RFapplications

Bell Labs, Amphenol

STStraight Tip fiber opticconnector

bayonet fiber optic ethernet AT&T

SC Subscriber/Square Connector snap-in fiber optic gigabit ethernet IBM

LC Local Connector (SFF) snap-in fiber optic gigabit ethernet Lucent

MT-RJMechanical TransferRegistered Jack (SFF)

snap-in fiber optic ethernet AMP

IEEE 1394 FireWire (i.Link) snap-indigital devices, consumerelectronics

Apple, Sony, Samsung,Matshusita, IBM, JVC,

USBUniversal Serial Bus (1.1 &2.0)

snap-indigital devices, computerperipherals

HP, Compaq, Lucent,Microsoft, Intel, NEC, Philips

Network connectivity devices

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Device Purpose Operation Remarks

HubConnects all nodes in a network together; transmissionsreceived in 1 port are rebroadcast to all ports

Layer 1concentrator (passive),repeater (active), MAU

SwitchConnects all nodes/segments in a network together; filtersand forwards packets; isolate collision domains

Layer 2multiport bridge, configureVLANs

BridgeConnects 2 network segments with dissimilar media types;isolate collision domains within a segment

Layer 2 wired or wireless

RouterConnects 2 networks with different topologies; mapsnodes & routes packets; isolates broadcast domains

Layer 3 Brouter, IOS

GatewayConnects 2 networks with different protocols ortechnologies; could be hardware or software

Layer 4, 5,6, 7

connection to ISP, PABX

NICAn expansion card installed in a device toconnect/interface to the network; particular to media &protocol

Layer 1, 2PCI, USB, PCMCIA, built-inM/B

CSU/DSUA 2 in 1 device used to connect a digital carrier to thenetwork equipment; provides diagnostics & buffering

- T1, T3; V.35 interface

ISDNadapter

The terminal adapter used to connect to the internet viaISDN technology

- BRI TA

WAPA device used to connect mobile PCs to a wired networkwirelessly via RF technology

Layer 1, 2 infrastructure mode, WiFi

ModemA device that changes digital to analog signal and viceversa; modulator/demodulator

- POTS (V.92), xDSL, cable

TransceiverA device that transmits or receives analog or digitalsignals; allows a NIC to connect to a different media type

- media converter, DIX/AUI

FirewallA stand-alone device or software used to protect networksfrom spyware, hackers, worms, phising, trojans

-port blocking, packetfiltering, proxy server, DMZ

Classful IP addressing

Class Range Default Subnet No of Subnets No of Hosts/Subnet

Class A 1.0.0.0 ~ 126.0.0.0 255.0.0.0 126 16,777,214

Class B 128.0.0.0 ~ 191.0.0.0 255.255.0.0 16,384 65,534

Class C 192.0.0.0 ~ 223.0.0.0 255.255.255.0 2,097,152 254

Reserved IP address blocks

CIDR address block Description Reference

0.0.0.0/8 Network or wire address RFC 1700

10.0.0.0/8 Private network (Class A) RFC 1918

14.0.0.0/8 Public data network RFC 1700

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39.0.0.0/8 Reserved RFC 1797

127.0.0.0/8 Localhost(Loop back address) RFC 1700

128.0.0.0/16 Reserved -

169.254.0.0/16 Zeroconf, APIPA RFC 3927

172.16.0.0/12 Private network(Class RFC 1918

192.0.2.0/24 Documentation and example code RFC 3330

192.88.99.0/24 IPv6to Ipv4 relay RFC 3068

192.168.0.0/16 Private network(Class C) RFC 1918

198.18.0.0/15 Network benchmark tests RFC 2544

223.255.255.0/24 Reserved RFC 3330

224.0.0.0/4 Multicasts(former Class D) RFC 3171

240.0.0.0/4 Experimental (former Class E) RFC 1700

255.255.255.255 Broadcast -

Physical and logical addressing

Version Length Notation Delimiter Separation Supports Example

MAC 48 bits Hexadecimal Colon ( ,Dash (-)

8-bit hexadecimaldigits (2 hex)

12x109

combinations00:50:DA:C3:8A:F9

IPv4 32 bitsDotted-decimal

Dots (.)8-bit binary codeddecimal digits

4.3x109

addresses207.142.131.235

IPv6128bits

Hexadecimal Colon ( 16-bit hexadecimaldigits (4 hex)

3.4x1038

addresses

2001:0DB8:0::0::1428:57AB

Rules of subnetting

No Rule

1 B bits => 2; R bits => 2

2 Usable subnets created = 2B - 2

3 Usable hosts per subnet = 2R

- 2

4 Decimal value of the number of bits borrowed = increment of the subnets

Commonly used well-known ports

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Port Name Function

20 FTP Reliable transfer of data; uses TCP

21 FTP Provides flow control; uses TCP

22 SSH Executes command and moves files; remote login protocol; uses TCP

23 TELNET Connects a remote computer to a server; uses TCP

25 SMTP Delivers emails between email servers; sending of emails; uses TCP

53 DNS Translates hostnames to IP addresses; uses TCP (zone transfers), UDP (queries)

69 TFTP Simple transfer of data; uses UDP

80 HTTP Opens a browser connection to a webpage; uses TCP

110 POP3 Delivers emails between a mail server and client; receiving of emails; uses TCP

119 NNTP Views and writes news articles for newsgroups; uses TCP

123 NTP Sets computer clock to standard time; uses UDP

143 IMAP4 Downloads emails; stores and searches messages from newsgroups; receiving of emails; uses TCP

443 HTTPS Allows browsers and servers to authenticate and encrypt network packets; uses SSL; uses TCP

Switching type comparison

Resource Circuit Switching Packet Switching

Dedicated path? yes no

Available bandwidth? fixed dynamic

Could Bandwidth be wasted? yes no

Store-and-forward transmission no yes

Each packet follows the same route? yes no

Call setup required not required

When can congestion occurs? at set-up at every packet

Charge? per minute per packet

Network protocols

Protocol Routing Addressing Naming Interoperability

IPX/SPX RIP, SAP, NLSP12-digithexadecimal

server names only: 64 characters,no special characters; NDS

Windows, Linux

NetBEUI unroutable -NetBIOS or computer names;WINS

Windows

AppleTalkversion1: unroutable;version2: RTMP

24-bit addressversion1: NBP; version2: IPnaming

ethernet: ELAP, tokenring: token talk

TCP/IP RIP, OSPF 32-bit address DNS, ARP, RARP Windows, UNIX, Linux,

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Mac, Novell

Digital transmission hierarchies

Carrier Channels Data Rate Format

T1 24 1.544 MbpsNorth American

T3 672 44.736 Mbps

E1 32 2.048 MbpsEuropean

E3 480 34.368 Mbps

J1 24 1.544 MbpsJapanese

J3 480 32.064 Mbps

Optical carriers

Level Data Rate

OC-1 51.84 Mbps

OC-3 155.52 Mbps

OC-12 622.08 Mbps

OC-24 1.244 Gbps

OC-48 2.488 Gbps

xDSL technologies

Type Distance Downstream Upstream Characteristic Use

ADSL 18,000 ft 1.544 Mbps ~ 6.1 Mbps 126 kbps ~ 640 kbpsMost popular; used for web access andmultimedia streaming

SDSL 12,000 ft1.544 Mbps(US), 2.048Mbps(EU)

1.544 Mbps(US), 2.048Mbps(EU)

WAN connection from company networkserver to phone company

HDSL 12,000 ft1.544 Mbps (2p), 2.05Mbps (3p)

1.544 Mbps (2p), 2.05Mbps (3p)

WAN connection from company networkserver to phone company

IDSL 18,000 ft 128 kbps 128 kbps Transmits data only; similar to ISDN BRI

CDSL 18,000 ft 1.544 Mbps

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TCP/IP protocol suite

Name Meaning Function

TCPTransmission ControlProtocol

Enables two hosts to establish connection and exchange network data;connection-oriented; guaranteed delivery of packets

UDP User Datagram Protocol Enables two hosts to establish connection and exchange network data;connectionless, unreliable, less overhead

FTP File Transfer ProtocolDownloads or uploads files between hosts; performs directory operations;also offers authentication security

SFTP Secure File Transfer ProtocolTransfer of files with SSH to provide encryption, public key authentication,and file compression; similar to FTP

TFTP Trivial File Transfer ProtocolFacilitates file transfer between computers; uses lesser bandwidth andfaster speed; similar to FTP; used in firmware downloading

HTTP HyperText Transfer ProtocolTransfer files or web pages from web server to client web browser; useslesser bandwidth and supports both text and graphics

HTTPSHyperText Transfer Protocol

Secure

Allows browsers and servers to authenticate and encrypt network packets

using SSL; secure version of HTTP

SMTP Simple Mail Transfer Protocol Uses a spooled or queued method to deliver or send emails

POP3 Post Office Protocol version 3Used to retrieve email files from the email server; can be used with orwithout SMTP

IMAP4Internet Message AccessProtocol version 4

Used to retrieve email files from the email server; similar to POP3 but withadded features; supports Kerberos

Telnet Telephone NetworkA terminal emulation program that connects remote computers to a server;execute a commands using command prompt

SSH Secure ShellA suite of protocols used to log into another computer on the network,execute commands, and secure transfer of files

ICMP Internet Control MessageProtocol Provides network layer management and control by sending datagrams andcontrol messages; works with IP

ARP Address Resolution ProtocolResolves network addresses (IP) into hardware addresses (MAC); usesaddress resolution cache table built into every NIC

RARPReverse Address ResolutionProtocol

Uses host MAC address to discover its IP address

NTP Network Time Protocol Sets computer clock to a standard time source usually a nuclear clock

NNTPNetwork News TransferProtocol

Used for the distribution, inquiry, retrieval, and posting of news articles andnewsgroup forum messages

SCP Secure Copy ProtocolSafe and secure copying of files between a local and remote computer;similar to SFTP

LDAP Lightweight Directory AccessProtocol

A session layer protocol that provides directory services and access to x.500information directories

IGMPInternet Group MulticastProtocol

A network layer protocol used to report multicast group membership toadjacent routers

LPR Line Printer Remote A printer protocol used to print across different NOS platforms

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Network services and protocols

Name Meaning Function

DNS Domain Name System Translates and resolves IP addresses into host names or the reverse

DHCP

Dynamic Host

Configuration Protocol

Allows a client device to request and obtain a unique IP address and other

parameters from a server automatically

NATNetwork AddressTranslation

Allows a local network to use one set of IP address for internal or in-housetraffic and a different set for external or internet traffic

ICSInternet ConnectionSharing

Connects multiple computers on a local network to the internet through asingle connection and IP address; uses NAT

WINSWindows Internet NamingService

Resolves a host NetBIOS name or computer name into an IP address; usedin legacy Windows

SNMPSimple NetworkManagement Protocol

Monitors the network and network devices; sends messages to different partsof the network; uses MIB

NFS Network File SystemPermits network users to access and used shared files; allows differentcomputer platforms to share files and disk space

Zeroconf Zero ConfigurationConnects networking devices using an Ethernet cable; no configuration orDHCP required

SMB Server Message BlockShares files, directories, and services; message format used by DOS; allowsUNIX/Linux and Windows machines to share files

AFP Appletalk File ProtocolA file sharing protocol used with TCP/IP to permit non-apple computers toaccess apple servers

LPD Line Printer Daemon Processes LPR print jobs, queues, and prints files

Samba - Provides file and print services to SMB clients; runs on UNIX and Linux

ICAIndependent ComputingArchitecture

The core of Citrix presentation server that enables Windows or UNIX serverto run an application for multiple users simultaneously

Apache - A popular public domain UNIX-based web server

Remote access protocols and services

Name Meaning Function

RASRemote AccessService

Used for client remote access to a network

PPPPoint-PointProtocol

Used to establish an internet connection between serial point-to-point links; providesfor dial-up connnections to networks

SLIP Serial Line InternetProtocol

Used to connect to the internet via a dial-up modem; older, slower, less reliable thanPPP

PPPoE PPP over EthernetUses PPP over Ethernet to connect an ethernet LAN user to the internet using anADSL or cable modem; users share a broadband connection

PPTPPoint-Point TunnelProtocol

A form of encryption that provides a tunnel for secure connections over the internet;used to create VPN

VPNVirtual PrivateNetwork

A private, secure, point to point connection from a company LAN to the remote usersand wireless nodes using the internet

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RDPRemote DesktopProtocol

connects a client to a network via a terminal server and uses authentication toestablish connection to run applications and printers remotely

Security protocols

Name Meaning Function

IPSecInternet ProtocolSecurity

Provides authentication and encryption over the internet; works with IPv4 and IPv6;used to secure VPN

L2TPLayer 2 TunnelingProtocol

Supports non-TCP/IP protocols VPN over the internet; combines the best features ofPPTP and L2F

SSLSecure SocketsLayer

Uses a private key to encrypt data that is transferred over the SSL connection;service independent and can secure different network applications

WEPWired EquivalentPrivacy

Encrypts and protects data packets over radio frequencies; does not offer end-endsecurity

WPA

WiFi Protected

Access

Offers improved data encryption and user authentication using the wireless devices

MAC address; uses TKIP encryption

AESAdvanced EncryptionStandard

A cryptographic cipher that uses Rijndael algorithm

PGP Pretty Good PrivacyAn encryption utility based on public key encryption designed to encrypt emailtransmissions

802.1x -Method for passing EAP over both wired and wireless networks; providesauthentication services for wireless networks not using PPP

Authentication protocols

Name Function

CHAPChallenge HandshakeAuthentication Protocol

Uses a hashed algorithm MD5 that provides client responseencryption; weak and one-way authentication protocol

MS-CHAP

Microsoft Challenge HandshakeAuthentication Protocol

Has two versions used in Windows systems that offers moresecurity; version1 not compatible with version2

PAP Password Authentication ProtocolThe weakest authentication protocol that sends username andpassword in clear text over the network to be verified by RAS

RADIUSRemote Authentication Dial-inUser Service

An industry standard that provides authentication, authorization, andaccounting services

Kerberos - A fully-fledge security system that uses secret key cryptography

EAP Extensible Authentication ProtocolA general protocol often used by a wireless devices to connect to aRADIUS server; TLS uses certificates such as smart cards

Routing protocols

Name Meaning Function

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RIPRouting InformationProtocol

Finds the quickest route between two computers; offers a maximum of 16 hopsbetween routers before deciding that a packet is undeliverable

OSPF Open Shortest Path FirstA descendant of RIP that increases its speed and reliability; much used on theinternet; accepts 256 hops between routers

IGRPInterior Gateway Routing

Protocol

A propriety protocol from Cisco that takes bandwidth, latency, reliability, and

current traffic load into consideration

EGPExterior GatewayProtocol

A distance vector protocol that uses polling to retrieve routing information

BGP Border Gateway ProtocolUsed to span autonomous systems in the internet; used at the edge of networks;designed to supersede EGP

NLSPNetware Link ServicesProtocol

A link state routing protocol that was designed to reduce wasted bandwidthassociated with RIP

RTMPRouting TableMaintenance Protocol

Used by Appletalk to ensure that all routers in the network have consistent routinginformation

Network operating system versions

Vendor Releases

Novell Netware 3.x, 4.x, 5.x, 6.x

Microsoft Windows NT, Windows 2000, Windows Server 2003

Apple Mac OS X, AppleShare IP

UNIX/Linux SCO ACE, RedHat

Server operating systems basic capabilities

OperatingSystem

Client Support Authentication File & Print Services Interoperability

UNIX/Linuxmulti-user,multitasking; GUI

etc/password; NISauthentication; LDAP

LPD/LPR; FAT16,FAT32, NTFS, Ext2,Ext3; NFS

Windows, Linux,Netware, Mac OS

Netwaremulti-user,multitasking; GUI

user password; keys stored inNDS; eDirectory

FAT16, FAT32, NTFS,NFS, AppleShare

Windows, Linux,Netware, Mac OS

Windowsmulti-user,multitasking; GUI

domain username/password;AD

LPD/LPR; FAT16,FAT32, NTFS

Windows, Linux,Netware, Mac OS

Mac OS multi-user,multitasking; GUI kerberos mechanism;keychain; OD UNIX-type file system,AppleShare IP Windows, Linux,Netware, Mac OS

TCP/IP utilities

Utility Operating System Function Switches

config NetWare displays IP stack configuration

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ifconfig UNIX/Linux displays IP stack configuration

winipcfg Windows 95/98 displays IP stack configuration

ipconfig Windows NT/2000/XPdisplays IP stack configuration, release/renewDHCP IP address, flush/register DNS

/all /renew /release/flushdns /registerdns

ping Windows/UNIX/Linux/Netwareverifies end-to-end network connectivity; usesICMP echo packets tanlfirv

tracert Windows 2000/XP/2003traces routes to internet sites based on thenumber of hops and displays time taken

dhjw

traceroute UNIX/Linuxtraces routes to internet sites based on thenumber of hops and displays time taken

netstat Windows/UNIX/Linux/Netwaredisplays protocol statistics and current TCP/IPnetwork connections

aberosnp

nbtstat Windows/UNIX/Linux/Netwaredisplays protocol statistics and current TCP/IPnetwork connections using NetBIOS overTCP/IP

aAcnrRSs

arp Windows/UNIX/Linux/Netware

displays and/or modifies IP to physical address

translation tables; displays current ARP cache agsN

nslookup Windows 2000/XP/2003queries a DNS name server; used totroubleshoot DNS and verify DNS resolution

adt exit

dig UNIX/Linux nslookup equivalent

telnet Windows/UNIX/Linux/Netwareenables a computer to function as a terminalworking from a remote computer

aeflt

netuse Windows NT/2000/XP used to connect to file or print share

Tools for network cabling and troubleshooting

Tool Usage

Wire crimper Used to affix an UTP/STP cable to a modular connector or plug

Punchdown tool Used to affix several cables to a punchdown block or a patch panel found in wiring cabinets

Mediatester/certifier

Used to test continuity or polarity of cables, trace shorts along the line; cant be used onlive/active wires

Tone generatorUsed along with a probe to verify cable continuity, identify wiring faults, determine line voltageand polarity; can be used in active wires

Common network implementation

Implementation Purpose Characteristics/Benefits Remarks

Firewall securityPermits/denies public traffic based on various filteringrules; protection from internet threats

ACL, DMZ

Proxy serversecurity,

performanceA firewall method that caches web content for improvednetwork performance; establish VPN for remote users

web proxy, ip proxy

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Antivirussoftware

security,maintenance

Software used to search/remove malicious programs onnetwork computer hard drives; prevents infection

viruses, worms,trojan horses

VLANsecurity,

performanceBetter bandwidth management; reduced administrationcosts; well-defined groups; improved network security

static/dynamic;VTP, DTP

Intranet cost, flexibility

A private network based on TCP/IP which resides

behind a firewall; cheaper, versatile, flexible informationsharing -

Extranet security, versatilityExtension of a corporate intranet; exchange databetween suppliers/customers; secure corporatepurchasing

-

Clusteringfault-tolerance,load balancing

A group of redundant mirrored servers; high availabilityand scalability; minimized network downtime

-

Network security implementation

Implementation Purpose Impact on network RemarksPort blocking intrusion detection slows down firewalls, proxy servers

Packet filtering intrusion detection slows down firewalls, proxy servers

Authentication access control none NOS logon server

Encryption data protection slows down IPSec, PKI, PGP, Kerberos, DES

Characteristics of fault-tolerance

Item Implementation

Power UPS, SPS; backup generators, cooling fans, processors; surge suppressor; line conditioners

Link redundancy Backup links: ISDN, dial-up; microwave wireless radios; secondary ISP; clustering

Storage Hardware or software RAID; SCSI hard disks; data warehousing

Services Mission critical servers and equipments: gateways, routers, switches; SAN clusters, MSOS

Disaster recovery Backup/restore schemes; offsite storage: NAS, SAN; hot/cold spares; hot, warm, cold sites

Types of RAID

Level No of drives Description

RAID 0 2 disk stripping without fault tolerance

RAID 1 2 disk mirroring/duplexing

RAID 0+1 4 a mirror of stipes

RAID 5 3 stripping with parity

RAID 10 4 stripe of mirrors

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Backup types

Type DescriptionClears archive

bit?Sets to restore

full/normal backs up all data; longest time to backup Y full only

incrementalbacks up files changed or added since the last backup; faster tobackup; uses more tapes

Yfull + everyincremental

differentialbacks up files changed or added since the last full backup; fasterto restore; uses lesser tapes

Nfull + last

differential

mirror/copy backs up all data; used to make offsite copies; N -

Types of backup tape drives

Drive Description CapacityData Transfer

Speed

QIC Quarter Inch Cartridge; formats: 3.5", 5.25" 20 GB, 50 GB60 kbps, 125kbps

Travan Enhancement of QIC; formats: TR4, TR5 4/8 GB, 10/20 GB1 Mbps, 1.83Mbps

DATDigital Audio Tape; formats: DDS (Digital Data Storage), DLT(Digital Linear Tape)

40 GB (DDS), 160 GB(DLT)

4.8 Mbps, 20Mbps

MammothAn 8mm backup format used in computer systems; AIT(Advanced Intelligent Tape)

10/20 GB, 20/40 GB 3 Mbps, 6 Mbps

Troubleshooting strategy

No Step

1 Identify the symptoms

2 Identify the affected area

3 Establish what has changed

4 Select the most probable cause

5 Implement a solution and action plan

6 Test the result

7 Recognize the effects of the solution

8 Document the solution and process

IEEE Standards

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Standard Description

802.1 Internetworking

802.2 Logical Link Control (LLC)

802.3 Ethernet (CSMA/CD)

802.4 Token bus LAN

802.5 Token ring LAN

802.6 Metropolitan Area Network (MAN)

802.7 Broadband technical advisory

802.8 Fiber optic

802.9 Integrated voice/data

802.10 Network Security

802.11 Wireless Networks

802.12 Demand Priority (100VG-Any LAN)

802.13 Not used

802.14 Cable modem

802.15 Wireless personal area network

802.16 Broadband wireless access

802.17 Resilient packet ring