Netplus Cheatsheet[1]
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Transcript of Netplus Cheatsheet[1]
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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
http://tools.ietf.org/html/rfc1700http://tools.ietf.org/html/rfc1700http://tools.ietf.org/html/rfc1918http://tools.ietf.org/html/rfc1918http://tools.ietf.org/html/rfc1700http://tools.ietf.org/html/rfc1700http://tools.ietf.org/html/rfc1700http://tools.ietf.org/html/rfc1918http://tools.ietf.org/html/rfc1700 -
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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
http://tools.ietf.org/html/rfc1797http://tools.ietf.org/html/rfc1797http://www.answers.com/topic/localhosthttp://www.answers.com/topic/localhosthttp://tools.ietf.org/html/rfc1700http://tools.ietf.org/html/rfc1700http://www.answers.com/topic/zeroconfhttp://www.answers.com/topic/zeroconfhttp://tools.ietf.org/html/rfc3927http://tools.ietf.org/html/rfc3927http://www.answers.com/topic/private-ip-addresshttp://www.answers.com/topic/private-ip-addresshttp://tools.ietf.org/html/rfc1918http://tools.ietf.org/html/rfc1918http://tools.ietf.org/html/rfc3330http://tools.ietf.org/html/rfc3330http://www.answers.com/topic/ipv6http://www.answers.com/topic/ipv6http://tools.ietf.org/html/rfc3068http://tools.ietf.org/html/rfc3068http://www.answers.com/topic/private-ip-addresshttp://www.answers.com/topic/private-ip-addresshttp://tools.ietf.org/html/rfc1918http://tools.ietf.org/html/rfc1918http://tools.ietf.org/html/rfc2544http://tools.ietf.org/html/rfc2544http://tools.ietf.org/html/rfc3330http://tools.ietf.org/html/rfc3330http://www.answers.com/topic/multicasthttp://www.answers.com/topic/multicasthttp://tools.ietf.org/html/rfc3171http://tools.ietf.org/html/rfc3171http://tools.ietf.org/html/rfc1700http://tools.ietf.org/html/rfc1700http://tools.ietf.org/html/rfc1700http://tools.ietf.org/html/rfc3171http://www.answers.com/topic/multicasthttp://tools.ietf.org/html/rfc3330http://tools.ietf.org/html/rfc2544http://tools.ietf.org/html/rfc1918http://www.answers.com/topic/private-ip-addresshttp://tools.ietf.org/html/rfc3068http://www.answers.com/topic/ipv6http://tools.ietf.org/html/rfc3330http://tools.ietf.org/html/rfc1918http://www.answers.com/topic/private-ip-addresshttp://tools.ietf.org/html/rfc3927http://www.answers.com/topic/zeroconfhttp://tools.ietf.org/html/rfc1700http://www.answers.com/topic/localhosthttp://tools.ietf.org/html/rfc1797 -
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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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8/3/2019 Netplus Cheatsheet[1]
15/15
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