Network+ (Tables & Charts)
Network
topologies
|
Topology
|
Description
|
Advantage
|
Disadvantage
|
|
Star
|
All nodes connect to a single
central device
|
Inexpensive & easy
|
If hub fails, network down;
maximum nodes = 1024
|
|
Bus
|
All nodes connect to a common
backbone
|
Simple & less cables
|
If backbone fails, network down;
both ends must be terminated
|
|
Ring
|
Each node is connected to two
other device
|
No collisions; less signal
degeneration
|
Expensive; difficult to
troubleshoot; proprietary hardware
|
|
Mesh
|
Each node connects to every other
device
|
Redundancy & fault tolerance
|
Expensive; complicated; difficult
to troubleshoot
|
Common
networking standards
|
Standard
|
Description
|
Speed
|
Access
Method
|
Topology
|
Media
|
|
802.3
|
Ethernet
|
10, 100, 1000 Mbps
|
CSMA/CD
|
physical star, logical bus
|
UTP, STP, fiber optics
|
|
802.5
|
Token ring
|
4, 16 Mbps
|
Token passing
|
physical star, logical ring
|
STP
|
|
802.11
|
Wireless networks
|
1, 11, 54 Mbps
|
CSMA/CA
|
cellular
|
Atmosphere
|
|
FDDI
|
Fiber Distributed Data Interface
|
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-TX
|
Cat5 UTP, Cat5e FTP
|
100 m
|
100 Mbps
|
RJ45
|
star
|
IEEE 802.3u
|
|
100BASE-FX
|
Micro MMF
|
412 m (half duplex)
2000 m (full duplex) |
100 Mbps (half duplex)
200 Mbps (full duplex) |
SC
|
star, point-point
|
IEEE 802.3u
|
|
1000BASE-T
|
Cat5e / Cat6 UTP (4 pairs)
|
100 m
|
1 Gbps
|
RJ45
|
star
|
IEEE 802.3ab
|
|
1000BASE-CX
|
Twinax STP
|
25 m
|
1 Gbps
|
HSSDC
|
star, point-point
|
IEEE 802.3z
|
|
1000BASE-SX
|
Micro MMF
|
550 m (50u)
275 m (62.5u) |
1 Gbps
|
SC
|
point-point
|
IEEE 802.3z
|
|
1000BASE-LX
|
SMF or MMF
|
550 m (MMF)
5000 m (SMF) |
1 Gbps
|
SC, LC
|
point-point
|
IEEE 802.3z
|
|
10 GBASE-SR
|
MMF
|
300 m
|
10 Gbps
|
850nm serial LAN
|
point-point
|
IEEE 802.3ae
|
|
10 GBASE-LR
|
MMF
|
10,000 m
|
10 Gbps
|
1310nm serial LAN
|
point-point
|
IEEE 802.3ae
|
|
10 GBASE-ER
|
MMF
|
40,000 m
|
10 Gbps
|
1550nm serial LAN
|
point-point
|
IEEE 802.3ae
|
Wireless
networking technologies
|
Standard
|
Data
Speed
|
Frequency
|
Transmission
Type
|
Topology
|
Range
|
|
IEEE 802.11 Legacy
|
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 802.11a WiFi
|
54 Mbps
|
5 GHz
|
OFDM
|
Point-point
|
30 m
|
|
IEEE 802.11g WiFi
|
54 Mbps
|
2.4 GHz
|
>20 Mbps: OFDM, <20 Mbps:
DSSS with CCK
|
Point-point
|
30 m
|
|
IEEE 802.11n WiFi
|
540 Mbps
|
2.4 GHz
|
MIMO
|
Point-point
|
50 m
|
|
Bluetooth
|
2 Mbps
|
2.45 GHz
|
FHSS
|
Scatternet
|
10 m
|
|
Infrared
|
100 kbps~ 16 Mbps
|
100 GHz ~ 1000 THz
|
Baseband
|
Point-point LOS
|
1 m
|
|
IEEE 802.16 WiMax
|
75 Mbps
|
2 GHz ~ 11 GHz, 66 GHz
|
BPSK
|
Point-point Cellular
|
30 km
|
The
Open Systems Interconnect reference model
|
No
|
Layer
|
Function
|
Unit
|
Protocols/Services
|
Devices
|
|
7
|
Application
|
network application services and
processes
|
data
|
FTP, TFTP, HTTP, SMTP, SMB, NCP,
Telnet, NTP, File & Print, DNS
|
gateway
|
|
6
|
Presentation
|
encryption, formatting,
compression, translation
|
data
|
ASCII, JPEG, GIF, TIFF, MIDI,
MPEG, MIME, Quicktime
|
gateway
|
|
5
|
Session
|
establishes maintains, manages
network connections and sessions
|
data
|
RPC, ZIP, SCP, SQL, NetBIOS, NFS,
ASP, LDAP, SSL, SMB
|
gateway
|
|
4
|
Transport
|
end-end error recovery,
connectivity, flow control
|
segments
|
TCP, SPX, UDP, NBP, NCP. NetBEUI,
SCTP
|
gateway
|
|
3
|
Network
|
routing, forwarding of packets;
sequencing of datagram
|
packets
|
IP, IPX, ARP, RARP, DHCP, BootP,
ICMP, RIP, BGP, OSPF, IPSec
|
router,
brouter
|
|
2
|
Data Link
|
encoding/decoding of packets into
bits; frame synchronization, error checking
|
frames
|
MAC, LLC, PPP, ATM, frame relay,
802.11b/g, L2TP, FDDI
|
switch,
bridge
|
|
1
|
Physical
|
electrical, mechanical, lightwave,
radio frequency, media specifications
|
bits
|
Ethernet, WiFi, Token Ring, BRI,
RS232, V.35
|
hub,
NIC, WAP
|
Physical
media types
|
Medium
|
Description
|
Types
|
Remarks
|
|
Twisted pair
|
Consists of multiple insulated
wires that are twisted together in pairs to prevent crosstalk
|
UTP, STP, ScTP
|
Cat3(16MHz), Cat5(100MHz),
Cat5e(100MHz), Cat6(250MHz)
|
|
Coaxial cable
|
Consists of a center conductor
surrounded by a plastic jacket with braided shield
|
75Ω, 50Ω
|
RG-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
|
Description
|
Lock
Method
|
Usage
|
Developed
by
|
|
RJ11
|
Registered Jack modular connector
(6P2C)
|
snap-in
|
telephone equipments, PBX
|
Bell Telephone Labs
|
|
RJ45
|
Registered Jack modular connector
(8P8C)
|
snap-in
|
twisted pair ethernet, PoE, ISDN,
T1, token ring
|
Bell Telephone Labs
|
|
F-type
|
F-type coaxial connector (75Ω)
|
screw-on
|
broadband cable, CATV, CCTV
|
|
|
BNC
|
Bayonet Nut Coupling (50Ω)
|
bayonet
|
thin ethernet, RF applications
|
Bell Labs, Amphenol
|
|
ST
|
Straight Tip fiber optic connector
|
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-RJ
|
Mechanical Transfer Registered
Jack (SFF)
|
snap-in
|
fiber optic ethernet
|
AMP
|
|
IEEE 1394
|
FireWire (i.Link)
|
snap-in
|
digital devices, consumer
electronics
|
Apple, Sony, Samsung, Matshusita,
IBM, JVC, …
|
|
USB
|
Universal Serial Bus (1.1 &
2.0)
|
snap-in
|
digital devices, computer
peripherals
|
HP, Compaq, Lucent, Microsoft,
Intel, NEC, Philips
|
Network
connectivity devices
|
Device
|
Purpose
|
Operation
|
Remarks
|
|
Hub
|
Connects all nodes in a network
together; transmissions received in 1 port are rebroadcast to all ports
|
Layer 1
|
concentrator (passive), repeater
(active), MAU
|
|
Switch
|
Connects all nodes/segments in a
network together; filters and forwards packets; isolate collision domains
|
Layer 2
|
multiport bridge, configure VLANs
|
|
Bridge
|
Connects 2 network segments with
dissimilar media types; isolate collision domains within a segment
|
Layer 2
|
wired or wireless
|
|
Router
|
Connects 2 networks with different
topologies; maps nodes & routes packets; isolates broadcast domains
|
Layer 3
|
Brouter, IOS
|
|
Gateway
|
Connects 2 networks with different
protocols or technologies; could be hardware or software
|
Layer 4, 5, 6, 7
|
connection to ISP, PABX
|
|
NIC
|
An expansion card installed in a
device to connect/interface to the network; particular to media &
protocol
|
Layer 1, 2
|
PCI, USB, PCMCIA, built-in M/B
|
|
CSU/DSU
|
A 2 in 1 device used to connect a
digital carrier to the network equipment; provides diagnostics &
buffering
|
-
|
T1, T3; V.35 interface
|
|
ISDN adapter
|
The terminal adapter used to
connect to the internet via ISDN technology
|
-
|
BRI TA
|
|
WAP
|
A device used to connect mobile
PCs to a wired network wirelessly via RF technology
|
Layer 1, 2
|
infrastructure mode, WiFi
|
|
Modem
|
A device that changes digital to analog
signal and vice versa; modulator/demodulator
|
-
|
POTS (V.92), xDSL, cable
|
|
Transceiver
|
A device that transmits or
receives analog or digital signals; allows a NIC to connect to a different
media type
|
-
|
media converter, DIX/AUI
|
|
Firewall
|
A stand-alone device or software
used to protect networks from spyware, hackers, worms, phising, trojans
|
-
|
port blocking, packet filtering,
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
|
|
|
10.0.0.0/8
|
Private network (Class A)
|
|
|
14.0.0.0/8
|
Public data network
|
|
|
39.0.0.0/8
|
Reserved
|
|
|
127.0.0.0/8
|
Localhost
(Loop back address)
|
|
|
128.0.0.0/16
|
Reserved
|
-
|
|
169.254.0.0/16
|
Zeroconf
, APIPA
|
|
|
172.16.0.0/12
|
Private network (Class
|
|
|
192.0.2.0/24
|
Documentation and example code
|
|
|
192.88.99.0/24
|
IPv6 to Ipv4
relay
|
|
|
192.168.0.0/16
|
Private network (Class C)
|
|
|
198.18.0.0/15
|
Network benchmark tests
|
|
|
223.255.255.0/24
|
Reserved
|
|
|
224.0.0.0/4
|
Multicasts
(former Class D)
|
|
|
240.0.0.0/4
|
Experimental (former Class E)
|
|
|
255.255.255.255
|
Broadcast
|
-
|
Physical
and logical addressing
|
Version
|
Length
|
Notation
|
Delimiter
|
Separation
|
Supports
|
Example
|
|
MAC
|
48 bits
|
Hexadecimal
|
Colon Dash (-)
|
8-bit hexadecimal digits (2 hex)
|
12x109 combinations
|
00:50:DA:C3:8A:F9
|
|
IPv4
|
32 bits
|
Dotted-decimal
|
Dots (.)
|
8-bit binary coded decimal digits
|
4.3x109 addresses
|
207.142.131.235
|
|
IPv6
|
128 bits
|
Hexadecimal
|
Colon
|
16-bit hexadecimal digits (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
|
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, NLSP
|
12-digit hexadecimal
|
server names only: 64 characters,
no special characters; NDS
|
Windows, Linux
|
|
NetBEUI
|
unroutable
|
-
|
NetBIOS or computer names; WINS
|
Windows
|
|
AppleTalk
|
version1: unroutable; version2:
RTMP
|
24-bit address
|
version1: NBP; version2: IP naming
|
ethernet: ELAP, token ring: token
talk
|
|
TCP/IP
|
RIP, OSPF
|
32-bit address
|
DNS, ARP, RARP
|
Windows, UNIX, Linux, Mac, Novell
|
Digital
transmission hierarchies Optical
carriers
|
Carrier
|
Channels
|
Data Rate
|
Format
|
|
T1
|
24
|
1.544 Mbps
|
North
American
|
|
T3
|
672
|
44.736 Mbps
|
|
|
E1
|
32
|
2.048 Mbps
|
European
|
|
E3
|
480
|
34.368 Mbps
|
|
|
J1
|
24
|
1.544 Mbps
|
Japanese
|
|
J3
|
480
|
32.064 Mbps
|
|
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 kbps
|
Most popular; used for web access
and multimedia streaming
|
|
SDSL
|
12,000 ft
|
1.544 Mbps(US), 2.048 Mbps(EU)
|
1.544 Mbps(US), 2.048 Mbps(EU)
|
WAN connection from company
network server to phone company
|
|
HDSL
|
12,000 ft
|
1.544 Mbps (2p), 2.05 Mbps (3p)
|
1.544 Mbps (2p), 2.05 Mbps (3p)
|
WAN connection from company
network server 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
|
<1.544 Mbps
|
Used in home and small business;
no splitter; known as G.lite
|
|
RADSL
|
n/a
|
640 kbps ~ 2.2 Mbps
|
270 kbps ~ 1.1 Mbps
|
Same as ADSL
|
|
VDSL
|
4500 ft
|
1.6 Mbps ~ 53 Mbps
|
1.5 Mbps ~ 2.3 Mbps
|
ATM networks using fiber optic
cable
|
TCP/IP
protocol suite
|
Name
|
Meaning
|
Function
|
|
TCP
|
Transmission Control Protocol
|
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 Protocol
|
Downloads or uploads files between
hosts; performs directory operations; also offers authentication security
|
|
SFTP
|
Secure File Transfer Protocol
|
Transfer of files with SSH to
provide encryption, public key authentication, and file compression; similar
to FTP
|
|
TFTP
|
Trivial File Transfer Protocol
|
Facilitates file transfer between
computers; uses lesser bandwidth and faster speed; similar to FTP; used in
firmware downloading
|
|
HTTP
|
HyperText Transfer Protocol
|
Transfer files or web pages from
web server to client web browser; uses lesser bandwidth and supports both
text and graphics
|
|
HTTPS
|
HyperText 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 3
|
Used to retrieve email files from
the email server; can be used with or without SMTP
|
|
IMAP4
|
Internet Message Access Protocol
version 4
|
Used to retrieve email files from
the email server; similar to POP3 but with added features; supports Kerberos
|
|
Telnet
|
Telephone Network
|
A terminal emulation program that
connects remote computers to a server; execute a commands using command
prompt
|
|
SSH
|
Secure Shell
|
A suite of protocols used to log
into another computer on the network, execute commands, and secure transfer
of files
|
|
ICMP
|
Internet Control Message Protocol
|
Provides network layer management
and control by sending datagrams and control messages; works with IP
|
|
ARP
|
Address Resolution Protocol
|
Resolves network addresses (IP)
into hardware addresses (MAC); uses address resolution cache table built into
every NIC
|
|
RARP
|
Reverse Address Resolution
Protocol
|
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
|
|
NNTP
|
Network News Transfer Protocol
|
Used for the distribution,
inquiry, retrieval, and posting of news articles and newsgroup forum messages
|
|
SCP
|
Secure Copy Protocol
|
Safe and secure copying of files
between a local and remote computer; similar to SFTP
|
|
LDAP
|
Lightweight Directory Access
Protocol
|
A session layer protocol that
provides directory services and access to x.500 information directories
|
|
IGMP
|
Internet Group Multicast Protocol
|
A network layer protocol used to
report multicast group membership to adjacent routers
|
|
LPR
|
Line Printer Remote
|
A printer protocol used to print
across different NOS platforms
|
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
|
|
NAT
|
Network Address Translation
|
Allows a local network to use one
set of IP address for internal or in-house traffic and a different set for
external or internet traffic
|
|
ICS
|
Internet Connection Sharing
|
Connects multiple computers on a
local network to the internet through a single connection and IP address;
uses NAT
|
|
WINS
|
Windows Internet Naming Service
|
Resolves a host NetBIOS name or
computer name into an IP address; used in legacy Windows
|
|
SNMP
|
Simple Network Management Protocol
|
Monitors the network and network
devices; sends messages to different parts of the network; uses MIB
|
|
NFS
|
Network File System
|
Permits network users to access
and used shared files; allows different computer platforms to share files and
disk space
|
|
Zeroconf
|
Zero Configuration
|
Connects networking devices using
an Ethernet cable; no configuration or DHCP required
|
|
SMB
|
Server Message Block
|
Shares files, directories, and
services; message format used by DOS; allows UNIX/Linux and Windows machines
to share files
|
|
AFP
|
Appletalk File Protocol
|
A file sharing protocol used with
TCP/IP to permit non-apple computers to access 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
|
|
ICA
|
Independent Computing Architecture
|
The core of Citrix presentation
server that enables Windows or UNIX server to run an application for multiple
users simultaneously
|
|
Apache
|
-
|
A popular public domain UNIX-based
web server
|
Remote
access protocols and services
|
Name
|
Meaning
|
Function
|
|
RAS
|
Remote Access Service
|
Used for client remote access to a
network
|
|
PPP
|
Point-Point Protocol
|
Used to establish an internet
connection between serial point-to-point links; provides for dial-up
connnections to networks
|
|
SLIP
|
Serial Line Internet Protocol
|
Used to connect to the internet
via a dial-up modem; older, slower, less reliable than PPP
|
|
PPPoE
|
PPP over Ethernet
|
Uses PPP over Ethernet to connect
an ethernet LAN user to the internet using an ADSL or cable modem; users
share a broadband connection
|
|
PPTP
|
Point-Point Tunnel Protocol
|
A form of encryption that provides
a tunnel for secure connections over the internet; used to create VPN
|
|
VPN
|
Virtual Private Network
|
A private, secure, point to point
connection from a company LAN to the remote users and wireless nodes using
the internet
|
|
RDP
|
Remote Desktop Protocol
|
connects a client to a network via
a terminal server and uses authentication to establish connection to run
applications and printers remotely
|
Security
protocols
|
Name
|
Meaning
|
Function
|
|
IPSec
|
Internet Protocol Security
|
Provides authentication and
encryption over the internet; works with IPv4 and IPv6; used to secure VPN
|
|
L2TP
|
Layer 2 Tunneling Protocol
|
Supports non-TCP/IP protocols VPN
over the internet; combines the best features of PPTP and L2F
|
|
SSL
|
Secure Sockets Layer
|
Uses a private key to encrypt data
that is transferred over the SSL connection; service independent and can
secure different network applications
|
|
WEP
|
Wired Equivalent Privacy
|
Encrypts and protects data packets
over radio frequencies; does not offer end-end security
|
|
WPA
|
WiFi Protected Access
|
Offers improved data encryption
and user authentication using the wireless devices MAC address; uses TKIP
encryption
|
|
AES
|
Advanced Encryption Standard
|
A cryptographic cipher that uses
Rijndael algorithm
|
|
PGP
|
Pretty Good Privacy
|
An encryption utility based on
public key encryption designed to encrypt email transmissions
|
|
802.1x
|
-
|
Method for passing EAP over both
wired and wireless networks; provides authentication services for wireless
networks not using PPP
|
Authentication
protocols
|
Name
|
|
Function
|
|
CHAP
|
Challenge Handshake Authentication
Protocol
|
Uses a hashed algorithm MD5 that
provides client response encryption; weak and one-way authentication protocol
|
|
MS-CHAP
|
Microsoft Challenge Handshake
Authentication Protocol
|
Has two versions used in Windows
systems that offers more security; version1 not compatible with version2
|
|
PAP
|
Password Authentication Protocol
|
The weakest authentication
protocol that sends username and password in clear text over the network to
be verified by RAS
|
|
RADIUS
|
Remote Authentication Dial-in User
Service
|
An industry standard that provides
authentication, authorization, and accounting services
|
|
Kerberos
|
-
|
A fully-fledge security system
that uses secret key cryptography
|
|
EAP
|
Extensible Authentication Protocol
|
A general protocol often used by a
wireless devices to connect to a RADIUS server; TLS uses certificates such as
smart cards
|
Routing
protocols
|
Name
|
Meaning
|
Function
|
|
RIP
|
Routing Information Protocol
|
Finds the quickest route between
two computers; offers a maximum of 16 hops between routers before deciding
that a packet is undeliverable
|
|
OSPF
|
Open Shortest Path First
|
A descendant of RIP that increases
its speed and reliability; much used on the internet; accepts 256 hops
between routers
|
|
IGRP
|
Interior Gateway Routing Protocol
|
A propriety protocol from Cisco
that takes bandwidth, latency, reliability, and current traffic load into
consideration
|
|
EGP
|
Exterior Gateway Protocol
|
A distance vector protocol that
uses polling to retrieve routing information
|
|
BGP
|
Border Gateway Protocol
|
Used to span autonomous systems in
the internet; used at the edge of networks; designed to supersede EGP
|
|
NLSP
|
Netware Link Services Protocol
|
A link state routing protocol that
was designed to reduce wasted bandwidth associated with RIP
|
|
RTMP
|
Routing Table Maintenance Protocol
|
Used by Appletalk to ensure that
all routers in the network have consistent routing information
|
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
|
Operating
System
|
Client
Support
|
Authentication
|
File
& Print Services
|
Interoperability
|
|
UNIX/Linux
|
multi-user, multitasking; GUI
|
etc/password; NIS authentication;
LDAP
|
LPD/LPR; FAT16, FAT32, NTFS, Ext2,
Ext3; NFS
|
Windows, Linux, Netware, Mac OS
|
|
Netware
|
multi-user, multitasking; GUI
|
user password; keys stored in NDS;
eDirectory
|
FAT16, FAT32, NTFS, NFS,
AppleShare
|
Windows, Linux, Netware, Mac OS
|
|
Windows
|
multi-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
|
|
|
ifconfig
|
UNIX/Linux
|
displays IP stack configuration
|
|
|
winipcfg
|
Windows 95/98
|
displays IP stack configuration
|
|
|
ipconfig
|
Windows NT/2000/XP
|
displays IP stack configuration,
release/renew DHCP IP address, flush/register DNS
|
/all /renew /release /flushdns
/registerdns
|
|
ping
|
Windows/UNIX/Linux/Netware
|
verifies end-to-end network
connectivity; uses ICMP echo packets
|
–t –a –n –l –f –i –r –v
|
|
tracert
|
Windows 2000/XP/2003
|
traces routes to internet sites
based on the number of hops and displays time taken
|
–d –h –j –w
|
|
traceroute
|
UNIX/Linux
|
traces routes to internet sites
based on the number of hops and displays time taken
|
|
|
netstat
|
Windows/UNIX/Linux/Netware
|
displays protocol statistics and
current TCP/IP network connections
|
–a –b –e –r –o –s –n –p
|
|
nbtstat
|
Windows/UNIX/Linux/Netware
|
displays protocol statistics and
current TCP/IP network connections using NetBIOS over TCP/IP
|
–a –A –c –n –r –R –S –s
|
|
arp
|
Windows/UNIX/Linux/Netware
|
displays and/or modifies IP to
physical address translation tables; displays current ARP cache
|
–a –g –s –N
|
|
nslookup
|
Windows 2000/XP/2003
|
queries a DNS name server; used to
troubleshoot DNS and verify DNS resolution
|
–a –d –t exit
|
|
dig
|
UNIX/Linux
|
nslookup equivalent
|
|
|
telnet
|
Windows/UNIX/Linux/Netware
|
enables a computer to function as
a terminal working from a remote computer
|
–a –e –f –l –t
|
|
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
|
|
Media tester/certifier
|
Used to test continuity or
polarity of cables, trace shorts along the line; can’t be used on live/active
wires
|
|
Tone generator
|
Used along with a probe to verify
cable continuity, identify wiring faults, determine line voltage and
polarity; can be used in active wires
|
Common
network implementation
|
Implementation
|
Purpose
|
Characteristics/Benefits
|
Remarks
|
|
Firewall
|
security
|
Permits/denies public traffic
based on various filtering rules; protection from internet threats
|
ACL, DMZ
|
|
Proxy server
|
security,
performance
|
A firewall method that caches web
content for improved network performance; establish VPN for remote users
|
web proxy, ip proxy
|
|
Antivirus software
|
security,
maintenance
|
Software used to search/remove
malicious programs on network computer hard drives; prevents infection
|
viruses, worms, trojan horses
|
|
VLAN
|
security,
performance
|
Better bandwidth management;
reduced administration costs; 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 information
sharing
|
-
|
|
Extranet
|
security,
versatility
|
Extension of a corporate intranet;
exchange data between suppliers/customers; secure corporate purchasing
|
-
|
|
Clustering
|
fault-tolerance,
load balancing
|
A group of redundant mirrored
servers; high availability and scalability; minimized network downtime
|
-
|
Network
security implementation
|
Implementation
|
Purpose
|
Impact
on network
|
Remarks
|
|
Port 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
|
Backup
types
|
Type
|
Description
|
Clears
archive bit?
|
Sets
to restore
|
|
full/normal
|
backs up all data; longest time to
backup
|
Y
|
full
only
|
|
incremental
|
backs up files changed or added
since the last backup; faster to backup; uses more tapes
|
Y
|
full
+ every incremental
|
|
differential
|
backs up files changed or added
since the last full backup; faster to restore; uses lesser tapes
|
N
|
full
+ last differential
|
|
mirror/copy
|
backs up all data; used to make
offsite copies;
|
N
|
-
|
Types
of backup tape drives
|
Drive
|
Description
|
Capacity
|
Data
Transfer Speed
|
|
QIC
|
Quarter Inch Cartridge; formats:
3.5", 5.25"
|
20 GB, 50 GB
|
60 kbps, 125 kbps
|
|
Travan
|
Enhancement of QIC; formats: TR4,
TR5
|
4/8 GB, 10/20 GB
|
1 Mbps, 1.83 Mbps
|
|
DAT
|
Digital Audio Tape; formats: DDS
(Digital Data Storage), DLT (Digital Linear Tape)
|
40 GB (DDS), 160 GB (DLT)
|
4.8 Mbps, 20 Mbps
|
|
Mammoth
|
An 8mm backup format used in computer
systems; AIT (Advanced Intelligent Tape)
|
10/20 GB, 20/40 GB
|
3 Mbps, 6 Mbps
|
Troubleshooting strategy IEEE
Standards
|
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
|
|
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
|
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