Messer 5 Flashcards
Which layer is called the post office layer
Transport Layer
Which layer utilizes port numbers
Transport
Which layer starts an stops communication
Session Layer
Which layers deals with Half and full duplex
Session Layer
Control and tunneling protocols are present in which layer
Session
Which layer deals with character encoding
Presentation Layer
Which layer deals with encryption
Presentation
Which layer are part of the Secure Socket Layer
Layers 5-7
Which layer adds a trailer and header
Link Layer of TCP IP model
Baseband is usually
A single cable
consumes bandwidth on wire 0 or 100%
Can be bidirectional
Broadband
Multiple signals over the same medium
Each signal uses its on freq or channel
Examples
Examples of broadband
Cable
Internet
VOIP
Describe Baud Rate
Associated with modems
Number of symbols per sec
Number of times signal state changes
Bit Rate
Bits maybe communicated in a single symbol
Total number of bits per sec is the bit rate
Bit vs Baud Rates
Bit Rate can be referred to the number of passengers
Baud rate can be associated with the number of train cars
High frequencies have long or short wavelengths
Short
TDM
Time Division Multiplexing
ISDN or Sonet networks
FDM
Frequency Division Multiplexing
Radio Stations
Wavelength division multiplexing
WAN networks
Fiber Connections
Base 16 Hex
4096
256
16
1
0=0 1=1 2=2 3=3 4=4 5=5 6=6 7=7 8=8 9=9 10=A 11=B 12=C 13=D 14=E 15=F
1 bite = 8 bits
Decimal value of 0x8
8
Decimal value of 0xC
12
Value for 14
E
Decimal value of 0X27
162=32
71=7
Total is 39
Decimal value of 0X3C
316=48
121=12
Total is 60
Hex value of 122 decimal
122/16=7 10/1=10 so 7=7 10=A
Answer 7A
Hex value of 350 decimel
350/*256 = 1
94/16 = 5
14/1=14
Answer is 0X15E
Octal Math
Base 8
Used with Unix or Linux
8 bits to make a byte
Octal conversion chart
512
64
8
1
Decimal value of 27 octal
8*2 = 16
7*1 = 7
16 + 7 = 23
Decimal value of 233 octal
64 * 2 = 128
8 * 3 = 24
1 * 3 = 3
128 + 24 + 3 = 155
Answer is 155
Octal value of 122 decimal
122 / 64 = 1 r58
58 / 8 = 7 r 2
2 / 1 = 2
Answer is 172 octal
Octal value of 200 decimal
200 / 64 = 192
8 / 8 = 1
0 / 1 = 0
Answer is 193 octal
CSMA/CD
Carrier Sense Multiple Access / Collision Detect
Half Duplex Ethernet
CSMA/CA
Carrier Sense Multiple Access /Collision Avoidance
Full Duplex
Used for wireless
uses RTS/CTS ready to send or clear to send
TCP IP Layers
Application
Transport
Internet
Link
TCP IP Suite application layer protocols
FTP DHCP TFTP DNS HTTP TLS SSL VOIP SSH POP3 IMAPv4 NTP Telnet SMTP SNMP
TCP IP transport layer protocols
TCP
UDP
TCP IP internet layer protocols
IPv4
IPv6
ICMP
IGMP
TCP IP link layer protocols
ARP
Wireless Network Standard
802.11
802.11a
5GHZ
54 Mbit/s
smaller range than 802.11b
signal absorbed by surroundings
No longer used
802.11b
2.4 GHz
11 Mbs
Better range less absorption
Freq range is congested
802.11g
2.4 GHz
54 MBs
backwards compatible with 802.11b
Freq congestion
802.11n
5 or 2.4 GHz
600 MBs
Uses MIMO
802.11ac
5GHz
Increased channel bonding
Denser signal modulation
8 MIMO streams
Security policy describes what
how data is secured
Name some agreements
SLA MOU informal MOA MSA - master service agreement multiple projects SOW
What’s a good humidity to control ESD
60% but this much humidity is very uncomfortable
What is fail open
all security features are opened automatically
What is Fail close
all security features are activated and closed during an emergency
name some passive cable termination
punch down block
patch panel
Main Distro Frame
Usually locatded in the data center
Serves as good test point
Central point of data
IDF
Intermediate Distro Frame
Extension of MDF
Houses switches for a floor
UPS
Backup power for 20 mins
Good for blackouts
brownouts
surges
Types of racks
Two post – telecommm equipment
Four Post
how is a data center air handled
Hot aisle
Cold aisle
FTP
Port 20/21
transfer files
USid and pasword
TFTP
Port 69
NO authentication
Very simple file transfer
Not used on production networks
SNMP
Port 161
Gather info about network devices
SNMP v3 has
integrity authentication and encryption
Telnet
Port 23
Login into remote devices
Clear txt passwords and usids
SSH
Port 22
Like a secure version of telnet
DNS
port 53
correlates ips to common names
DHCP
Port 67/68
Dynamic or Static
smb
Port 137/138/139
Server message block
Called a common Interment File System
RDP
Port 3389
TCP
Connection oriented
Reliable delivery
Can handle out of order messages
UDP
Connecitionless
No formal setup or tear down
Fire and forget
Unreliable
Ephemeral Port
Temporary ports
Non Ephemeral Port
Permanent port numbers
Usually on servers
HTTP Port
80
443
NetBIOS Port
137
138
139
POP
110
For receiving client email
IMAP
143
new email client protocol
SMTP
25
Transfer email between email servers
SIP
5060/5061
Session Intiated Protocol
Voice over IP signaling
MGCP
2427
RTP
5004/5005
H.323
1720
Done
Done