Chapter 6 - Network Security Flashcards
(156 cards)
0
Q
What is the tcp/ip model
A
Predecessor to the OSI model, had 4 layers instead of 7 application is one instead of 3 layers
1
Q
What ISO is the OSI model
A
ISO 7498
2
Q
What are the OSI layers?
A
Physical Data link Network Transport Session Presentation Application
3
Q
Open network architecture
A
A non proprietary architecture no one owns
4
Q
Encapsulation
A
Appending data to a packet one OSI layer at a time in a wrapper
5
Q
Application Layer 7
A
Application protocol layer, software accesses API to common protocols like HTTP SMTP FTP each of which starts the OSI process and hands off to the presentation layer
6
Q
Presentation layer 6
A
Data is converted to a standard and may be encrypted and/or compressed.
Ex word 2010 document is made in application layer, at presentation layer this becomes ASCII and at another workstation this ASCII is opened in open office to view the file
7
Q
Session Layer 5
A
This is where the data is sent from application to application.. This is where the server/client pieces have relevant association. The session is controlled by the software still at this point, authentication requirements live here
8
Q
Transport layer 4
A
TCP/UDP type network sessions are handled and maintained at this layer
SSL resides here due to network level encryption
9
Q
Network layer 3
A
IP and routing protocols live here
10
Q
Data link layer 2
A
Logical link control - LLC
Media access control - MAC
11
Q
Logical link control
A
Interprets network data and converts it to a MAC addressing aware format
12
Q
Media access control MAC
A
This is what specifies the appropriate voltage output. MAC addressing is also encapsulated in the packet. Different media requires different voltages, these decisions occur here
13
Q
Physical layer 1
A
Transmits the voltage specified by the MAC into or from the wire
14
Q
What are the port ranges?
A
Well known 0-1024
Registered 1024-49151
Dynamic 49152-65535
15
Q
SYN proxy
A
Software that will hold onto the connection until the tcp handshake is complete
16
Q
TCP session hijacking
A
This is done by predicting the sequence number and inserting packets into the stream
17
Q
Protocol data units
A
Data - application layer Transport - segments Network - packets Data link - frames Physical - bits
18
Q
CIDR
A
Classless inter domain routing / supernetting
19
Q
Type of service
A
QoS?
20
Q
IPng
A
IPv6
21
Q
Jumbo grams
A
Massive oversize packets, aka jumbo packets
22
Q
Automatic tunneling
A
A technique used to autonegotiate and build tunnels
23
Q
6to4
A
Embeds ipv4 in ipv6 remotely
24
Teredo
Remote UDP tunneling
25
ISA-TAP
Ip4 to ip6 virtual map used for local association
26
Security issues with ipv6
Biggest is having tunneling on and accessible and not knowing it
27
802.1AE
MACSec - switch to switch encryption
28
802.1AR
Provides unique iD that can be used for authentication 802.1AE
29
802.1X
EAP-TLS
30
Bandwidth vs throughput
Bandwidth is the maximum amount of throughput possible
31
Multistation access unit
Used in token ring as a central switch
32
Carrier sense multiple access / collision detection
CSMA/CD
Used to sense if a line is free and if collisions are occurring on the wire
33
Back off algorithm
When a collision is sensed all systems wait a random amount of time before sending a new frame
34
CSMA/CA
CSMA with collision avoidance.. It waits till it's clear then tells everyone to shut up and it transmits
Used by 802.11
35
Collision Domain
A set of systems contending for the same piece of physical media
36
What protocol assigns the group in multicast?
IGMP
37
DORA
Discover
Offer
Request
Ack
38
RARP
A MAC is sent out and a server sends an IP to the requester
Reverse arp
This evolved into bootp then dhcp
39
Arp poisoning
Modifying he arp table to send data to an attacker
40
Ping of death
When oversized sized packets are sent to ddos a system
41
Smurf attack
A spoofed icmp echo is sent to a broadcast address and all machines on a network will reply to the spoofed address, ie the ddos machine
42
Fragile attack
Same as smurf, over udp
43
Managed information base MIB
A logical group of managed objects that contain management task data
44
Communities
Establish a trust between MIB agents/server
45
Community string
A community password
46
DNSSEC
Secure DNS that requires a digital signature before responding and caching
47
Split DNS
External queries are handled by wan side servers only, internal queries are only handled by internal servers are are not accessible externally, these should forward recursion to the external servers
48
URL Hiding
Hiding a URL in an HTML link
49
SASL
Framework for protocol independent authentication for SMTP
50
Email spoofing
Using an email address that looks like it is legitimate but is not
51
SMTP-AUTH
Used to verify the sender of a message
52
Sender Policy Framework SPF
A DNS entry that is generated to associate a specific server to the email server
53
Whaling attack
Targeting largely important people in a company and very specifically engineer an email to trick then
54
Autonomous System (AS)
An internal network isolated by BGP
55
Distance Vector Routing Protocol
Uses # hops and distance as a decision maker for the route
56
Link state routing protocols
Chooses routes based on link speed, packet size, delay, load and reliability
57
VRRP
A virtual interface that is mapped to two different actual routers
58
Exterior Gateway Protocols
eBGP
59
Routing policy
An administrative weight override
60
Bridge
Used to extend a LAN segment
61
Source routing
Routing information is put into the packet at creation, this is dangerous
62
How are layer 3 switches more efficient than routers?
They use hardware based port tagging
63
802.1Q
VLAN
64
VLAN Hopping Attacks
VLAN tags are inserted into the headers to fake VLAN access
65
Private branch exchange
PBX system used to translate phone data streams
66
Phreakers
Phone hackers
67
How does MPLS work?
It uses packet tagging just like a layer 3 switch, which is why it is more reliable
68
Egress vs ingress
Ingress is inbound
| Egress is outbound
69
How do stateful firewalls work?
They keep track of a connection state in a state table. This scans headers and verify protocol rules are not being broken
70
What is the difference between circuit level and application level proxy?
Circuit level is layer 1-4 inspection
Application level is layer 1-7 inspection
Both recreate the traffic
71
SOCKS firewall?
Look it up, no idea
72
What is a dynamic packet filtering firewall?
A firewall that dynamically add outbound source based rules for requests from inside to specific systems outside, this assists with avoid any out rules
73
Appliances
OS layer software used for a specific and isolated purpose. Everything is locked down other than that one purpose
74
Kernel firewalls
This is a firewall specific kernel design to interface directly with hardware
75
Bastion Host
A highly exposed system that is most likely to get targeted and most hardened
76
Screened host
A firewall behind a router that has packet analysis
77
Screened subnet
Fancy name for DMZ
78
Silent rule
Drop noisy traffic to reduce logs
79
Stealth rule
Disallows traffic from unauthorized systems to firewall software
80
Cleanup Rule
Log traffic allowed
81
Negate rule
Specific deny rules
82
Forwarding proxy
Handles the traffic on behalf of another computer
83
Open proxy
Anonymous proxy
84
Reverse proxy
A proxy that does not hide the identity of the source and handles inbound traffic
85
Honeypot
A sweet server to hack into that detracts attention away from priority systems long enough to discover the offender
86
Tarpit
A system with ultra slow response that will cause timeouts and inconsistency for the automated hacking tools
87
Extranet
An internal network that extends to other companies, like EDI
88
Value added network
A company between companies handling EDI traffic
89
Sonet
Synchronous optical network
Used in MANs by ISPs to handle city and nationally wide infrastructure
90
Synchronous digital hierarchy
This is the world wide standard used version of sonet ring (US only) and varies in speed and density
91
Multiplexing
Running multiple channels at once sending data per channel per frame,
One frame has 8 bits of each channel being multiplexed in a T1 (24 channels)
92
What is an E carrier?
This is the world standard instead of T lines in the US
E1 - 2.048 Mbps
93
OC - x
This is the optical carrier used for the Internet backbone
Scale has 4 OC - 192s
94
Statistical time division multiplexing
STDM - transmit several types of data over a cable (T1)
95
Frequency division multiplexing
FDM - an available wireless channel is split up into smaller multiple channels then used for multiplexing
96
Wave division multiplexing
Laser wavelength multiplexing
97
CSU/DSU
Used by T telecom to multiplex data into separate channels per frame
98
Circuit switching
Switching changes made within an ISP to simulate a dedicated line
99
Packet switching
This is how the interwebs works
100
Committed information rate
Higher cost to guarantee services
101
Frame relay
Switching based dedicated links
102
Permanent virtual circuit
This is a dedicated line connected to a frame relay cloud
103
Switched virtual circuits
Dynamically makes a dedicated switch circuit as needed
104
ATM
Asynchronous transfer mode
Like frame relay but better
Uses 53B fried frames to optimize switching
105
What are the bit rates for QOS?
Constant - prioritize connection oriented
Variable - de-prioritize connection oriented
Unspecified - no specification
Available - the bit rate changes by availability
106
What are the levels of QoS?
Best effort - no guarantees
Differentiated - shorter delays
Guaranteed - first in line
107
Traffic shaping
uses QoS to maintain bandwidth levels
108
Switched multimegabit data service
Antiquated packet switching service
109
Synchronous data link protocol
Mainframe datalink layer switching protocol used between mainframes
110
High level data link control
Mainly used for device to device communication like router to router
111
LCP/NCP
LCP is link control protocol and handles the connection of a PPP
NCP is network control protocol and controls the authentication
112
SLIP
Serial line internet protocol - old technology used to connect serial lines. PPP replaced it
113
High speed serial interface HSSI
Used for an interface to connect multiplexers and routers to high speed ATM and frame relay
114
Multiservice access technology
Running several services at the same time like voice and data
115
PSTN - public switched telephone network
Old technology that used circuit switching instead of packet switching .. Think of POTS
116
H.323
Conversion gateways between the circuit based PSTN to the packet based VOIP
117
Vishing
A telephone phishing attack where people call you trying to get information
118
SIP
Three way handshake used to establish IP telephony connections for conferences and VOIP
119
SIP process
```
Caller Invite
Server sends Trying
Receiver Ringing
Receiver sends Ok
Caller Ack
```
120
What is RTP?
Standardized packet format for delivering audio / video
121
What is a VoIP registrar used for?
Keeps a centralized record of the updated locations
122
What is RTCP?
Provided feedback on RTP
RTP control protocol
123
Is SIP encrypted?
Nope!
124
SPIT
Spam over ip telephony
This is VoIP spam and causes voicemail overload and wasted time
125
What is an ISDN bri/pri?
BRI - 2 channel home quality ISDN 144kbps
| PRI - 23 channel commercial quality ISDN often used as an on demand redundant connection
126
What are the types of DSL?
```
Sdsl - slow symetrical service
Adsl - faster asymetrical service
Hdsl - faster yet asymetrical
Vdsl - fastest asymetrical service
Radsl - rate adaptive based in media
```
127
What is DOCSIS?
A standard for adding high speed data transfer over existing cable infrastructure
128
Layer 2 tunneling protocol
Used to traverse layer 2 point to point (PPP) networks like MPLS
129
How does IPSec work?
IP Tunnel Encryption Protocol
130
Authentication header (AH)
Used for data integrity, data origin, protection from replay
131
Encapsulating security payload (ESP)
Provides confidentiality, and integrity
132
ISAKMP
Provides a framework for security
133
IKE
Authentication Ceritcifcate keys
134
HAIPE
A layer 3 VPN tunneling protocol used mostly by the NSA as a replacement for PPP/L2TP devices and methods
135
Transport adjacency
More then one security policy used in a VPN.
136
Iterated tunneling
Tunnels within tunnels
137
What is PAP?
Clear text authentication used over PPP
138
How does CHAP work?
It is a challenge response authentication..
A random number (challenge) is encrypted with a predefined password and sent for verification
139
EAP
Is a framework to enable authentication and has many variants like
EAPGSS - generic security service using Kerberos
EAPTLS - digital certificate based authentication
140
Spread Spectrum
Parrellel wireless over multiple frequencies
141
Frequency hopping spread spectrum - FHSS
Frequency hopping is when sub-spectrums are used in a particular order to reduce the possibility of collision
1-2 Mbps
142
Direct sequence spread spectrum -DSSS
A chipping number is placed in each transmission and randomized only the proper chipping sequence can interpret the data, offers resend capability
11 Mbps
143
Orthogonal frequency division multiplexing OFDM
Used to tightly and precisely pack signals near each other using different perpendicular modulation
52 Mbps +
144
What is open system authentication?
Non-encrypted wireless ssid
145
Shared key authentication
Wireless that used challenge / response to encrypt the communication
146
802.11i
Standard for wireless security
147
802.1x
Allows for authentication as a separate process since it is at the networking level
148
Bluejacking
Sending a user something like a contact or message via Bluetooth connection
149
Bluesnarfing
Getting access to personal information through a Bluetooth connection
150
What allows wireless mobile devices to use the limited frequency of radio?
Each tower uses a different frequency and no adjacent tower can use the same
151
FDMA
1G - first gen. Used sub band frequencies per call, this ran out quickly.
152
TDMA
Time slice of a frequency allows no one user to hog a frequency - GSM
153
CDMA
3G - spread spectrum using the entire bandwidth for each user call
154
OFDMA
Frequencies are extremely closely packet using narrow sub channels to get the most bandwidth.. This is where 4G comes in.
155
Cell phone cloning
The use of someone's cell phone credentials to utilize calls on their account
