Software Defined Networking Flashcards
1
Q
SDN
A
Software Defined Networking
Allows us to architect networks that are directly programmable from a centralized controller
Works by abstracting the Control Plane into a software controller
Controller centralizes the control plane of multiple network devices
Allows us to pre=program network behavior
2
Q
Control Plane
A
Learning/programming what we will do
3
Q
Data Plane/Forwarding Plane
A
Routers and switches, actually moving packets and frames through the network
4
Q
WAN Connections
A
MPLS, Metro-E, Leased Lines, VPN, ATM, Frame-Relay, SONET, DSL, PPP, Cable, Dialup, Satellite, Cellular WAN
Circuit Switching and Packet Switching
5
Q
Circuit Switching
A
Creates a dedicated circuit across the WAN
All data takes the same path and the circuit bandwidth is reserved
“static”
Dedicated Circuit and data can only travel one pathway
Older WAN technologies based on Circuit Switching:
PSTN (Public Switch Telephone Network)
Dialup
ISDN (Integrated Services Digital Network)
6
Q
Packet Switching
A
Transmits data in packets
The network paths are shared (NOT a dedicated circuit)
“dynamic”
Packetized data that can travel multiple different paths
All current WAN technology is based on Packet Switching:
IP (Internet Protocol)
Frame Relay
ATM (Asynchronous Transfer Mode)
MPLS (Multiprotocol Label Switching
7
Q
Private WAN Connection Types
A
MPLS, Metro-E, Leased Lines, VPN
Older Technologies:
ATM, Frame-Relay, SONET, DSL, PPP, Cable, Dialup, Satellite, Cellular WAN
8
Q
MPLS
A
Multi-Protocol Label Switching
Uses label-switching routers and label edge routers (does “tagging” and tags things w/ labels)
Supports multiple protocols like IP, Frame Relay and ATM
High speed WAN connectivity (10Mbps, 50 Mbps, 100Mbps, 1Gbps +)
Trasnport works between layers 2 and 3 (layer “2.5” protocol)
One of the most prominent WAN technologies in the present day “For connecting facilities (sitsS) across the WAN”
9
Q
Metro-E
A
Metro Ethernet (Metropolitan Area Ethernet)
Can be pure Ethernet, but usually uses other technologies on the provider netowrk such as MPLS
High speed WAN connectivity (Ethernet speeds)
10
Q
Leased Lines
A
AKA Dedicated Lines
Private poin to point connection
Bsaed off of multiple DS0 (64Kbps) chunks
Technically a T1 line (24 DS0 lines) is enough room to handle 23 phone calls plus the D channel
Uses ESU/DSU to terminal the signal at the customer site
11
Q
VPN
A
Virtual Private Network
Encrypted private tunnel between two locations
Establishes a private network over any other networks such as the public internet
Can use VPNs over the public internet to create private WAN connections
VPNS are created between routers or between firewalls
12
Q
ATM
A
Asynchronous Transfer Mode
Uses fixed length cells (packetized data) instead of Frames
Was highly used on Campus networks until Ethernet replaced it
Back bone for some provider DSL implementation
Uses virtual circuits and the data rates are measured as optical carrier rates
Still in use with SONET
13
Q
Frame Relays
A
Routers from different branch locations connect into the Frame Relay network using Virtual circuits and supports standard T1 and T3 lines
Point to point or point to multi-point
Works at layer 2 of OSI model
MPLS/Metro-E slowly replacing it
14
Q
SONET
A
Synchronous Optical Networking
Works at the physical layer of OSI
Can carry higher level protocols such as ATM and IP
Defines optical carrier (OCx) base data rate of 51.84Mbps (Oc-1)
15
Q
DSL/ADSL
A
Digital Subscriber Line
Uses residential phone lines for internet access and POTS service can be provided on the same line
ADSL up to 8Mbps down stream / 1.544Mbps upstream
VDSL (rare) up to 52Mbps downstream / 12Mbps upstream
16
Q
PPP/Multilink PPP
A
Point to point protocol
Used for connecting with various WAN services such as DSL and Dial Up
Username and password authentication (PAP, CPAP, MS-CPAP)
Multilink PPP for bounded connections such as with multiple T-1 leased lines
17
Q
PPPoE
A
Point to Point Protocol over Ethernet
Often used with DSL Modems
Allows PPP authentication over Ethernet
18
Q
Broadband Cable
A
Residential and commercial internet connectivity
Generally faster than DSL
Cable modems use F-type connectors
19
Q
Dial Up
A
Uses residential phonelines with a modem for internet access and PPP for signing into the connection (with username and password)
Old, slow, not good even for a backup connection
20
Q
Satellite
A
High latency
Used for backup internet connectivity/rual areas
Downloads up to 12Mbps and uploads up to 3Mbps
Uses RG-6 cable (coaxial cable)
21
Q
Cellular WAN
A
Cellular technologies: GSM, CDMA, WiMAX
Very useful and great speeds
4G normally in the 10s of Mbps on the download peaking near 1000Mbps (depending on location)
Great for remote sites and backup connectivity
22
Q
WAN Outage
A
Critical Outage
Is the problem on the provider side or the customer side?
23
Q
MDF
A
Main Distribution Frame
Our main IT room, where the WAN circuit comes our network
Connection comes through MDF to connect into the customer’s equipment
24
Q
IDF
A
Intermediate Distribution Frame
25
CSU/DSU
Channel Service Unit / Data Service unit
Converts digital data frame from LAN communication technology into a frame appropriate for a WAN and vice versa
26
Demarcation Point
The demarcation point is a boundary between the service provider's and customer's networks
This is where the PE (Provider Edge ~ Comcast) Equipment is held: the router, modem, csu/dsu
A WAN circuit is connected into a smart jack (NIU) or network interface unit or patch panel and they terminate the WAN circuit to that device
27
Circuit ID
Every circuit has an ID
Normally it's written on something (a tag) at the Demarcation point, in the Demarc room, or near the smart jack
28
Circuit Label
long series of numbers and letters. A label or tag on the cable
29
PE
Provider Edge
Where the PE equipment is. If there is no equipment then the provider edge would be at the smart jack, NIU, or patch pannel
30
CE
Customer Edge
The customer equipment where it plus into the provider network
31
CE Router
Customer Edge Router
Which should be in the MDF. It connects into the provider equipment
32
CPE
Customer Premise Equipment
Same as CE Router,it's the equipment on t he customer's location that actually interfaces with the telecom provider and plugs into their network
33
Loopback
Basically takes the transmit and brings it back to the receiver, loops back on itself and should bring the circuit up on one side (generally)
34
WAN Probelms
Loss of Connectivity
Interface Errors
Router Configurations
Bad Smart Jack or NIU
Security Policies
Line drivers CSU/DSU and modems
DNS
35
Loss of Connectivity
First thing to do is check the equipment and call the provider to open a ticket. May need to troubleshot CPE with provider
36
Interface Errors
Physical problems on the line, interface synchronization or signaling problems
Could reside on the provider network, provider edge, customer edge or any of the devices/cables in between
37
Router Configurations
Interface configurations, speed and duplex, IP address configurations, routing protocols such as BGP, static routes, etc.
38
Bad Smart Jack or NIU
Networking Interface Unit
The provider can test to the smart jack and verify if the connection is good
39
Security Policies
Access lists or firewall rules blocking certain connections. Throttling traffic due to security policy
Could be a misconfiguration causing the wrong users to have access blocked or WAN bandwidth throttled down
40
Line Drivers, CSU/DSU, and Modems
Sometimes a WAN fault may reside at the line driving or modulating component
Older WAN circuits use CSU/DSU and modems to push the signal
If the devices are out of synch or not fully connected then the circuit will not function
41
DNS
Domain Naming Service
Loss of internet connectivity can be a problem with DNS such as incorrect IP address or the DNS server is down
Results in no web access even if the WAN/Internet connection is up and running
42
Smart Jack
Let s the provider company test circuits remotely without sending a tech onsite
43
Loopback Plug
Used to create a hard loopback on the circuit or device such as a router or CSU/DSU
44
WAN Circuits
Have circuit IDs used to identify the circuit when a problem is called into the provider
45
SOHO
Small Office / Home Office
46
802.11
Main Wireless LAN standard
47
Infrastructure Mode
Devices communicate through a wireless access point to access the main LAN. Traditional wifi
Require an AP (Access Point)
48
2.4GHz
802.11 B, 802.11 G, and 802.11 Are all 2.4Ghz standards
49
802.11A
5Ghz only, 54Mbps on our connection to the WAP
First standard
Original wireless standard extensions
Modulation: DSSS (direction Sequence Spread Spectrum) or OFDM (Orthogonal Frequency Division Multiplexing)
50
802.11 G
2.4Ghz, 54 Mbps when connected to WAP
Greatly accelerated Wifi adoption
Modulation: DSSS (direction Sequence Spread Spectrum) or OFDM (Orthogonal Frequency Division Multiplexing)
51
802.11 N
Supports both 2.4Ghz and 5Ghz, 600Mbps when connected to WAP
Brings MIMO (Multiple Input, Multiple Output, with 4 partial streams and the fastest wireless LAN speeds
Modulation: OFDM (Orthogonal Frequency Division Multiplexing)
52
Wireless NIC / Wireless Clients
Laptops, tablets, cell phones, many more devices
53
Wireless AP
Wireless Access Point
Standalone AP
SOHO wireless router / combo device (provides wireless and ethernet connections)
Should be placed with overlapping coverage to allow clients to roam between them
54
Ad Hoc Mode
Devices connect directly via wifi without using a wireless access point
Can cause problems with printers, think WDS ports
55
SSID
Service Set Identifier
Wireless network name.
56
BSSID
(Basic SSID) single WAP, single SSID
57
ESSID
(Extended SSID) multiple WAPS in the same SSID. Clients can roam between WAPs
58
LWAPP
Light Weight Access Point Protocol
Allows for control of multiple WAPS via a centralized wireless controller server
APs pull their configurations from the centralized wireless controller
LDAP is the protocol responsible for our wireless controllers
59
CAPWAP
Control and Provisioning of Wireless Access Points
Based on LWAPP but with added security
60
Frequency Bands
2.4Ghz and 5Ghz
61
ISM Bands
Industrial, Scientific, Medical bands
62
802.11 AC
5Ghz
MIMO with 8 partial streams
With 8 antennas up to 6.77Gbps when connected to WAP
Modulation: OFDM (Orthogonal Frequency Division Multiplexing)
63
802.11 B
2.4Ghz, 11Mbps when connected to WAP
Original wifi standard extension
Modulation: DSSS (direction Sequence Spread Spectrum)
64
5Ghz
802.11 A, 802.11 N, and 802.11 AC are all 5Ghz standards
65
2.4Ghz Frequency Channels
Channels 1,6,11 for least interference or overlap as the channels 1-11 all overlap with the two channels on either side of them
66
MIMO
Multiple Input, Multiple Output
allows us to use multiple antennas to get more bandwidth out of the wireless connection, up to 600Mbps
67
Wired vs Wireless
Wired is always better than wireless as wireless has inherently high latency
Wireless is half duplex, meaning it can only communicate in one direction at a time
Important infrastructure devices should always be connected via wired
68
Wireless Spectrum Analyzer
Broadcasting SSIDs
Frequency Bands
Channels used
Channel saturation
Dead spots
Interference
Software and hardware
69
Wireless Survey Tool
Heat map
Planning
Verification
Reporting
Can include spectrum analysis tool
Used for whenever we're planning out our wireless installation and then to verify it
70
Wireless Surveys
Planning survey (before install)
Verification survey (after installation)
71
Verification Surveys
After installation
Documentation / Report
Show proper wireless implementation
Show improvements to coverage, dead spots, channel utilization, etc.
72
Planning Survey
Survey WiFi coverage / heat map
Identify broadcasting SSIDs
Locate existing AP positions
Identify channels used and overlap
Identify dead spots
73
Overlapping Coverage
Overlapping coverage for location, but not for channels/frequencies
74
Honeycomb Overlap
Think of 6 hexagons making a larger hexagon with equal coverage over each AP
For 2.4Ghz and 5Ghz
75
Single Cell Separation
2.4Ghz channels must be separated by 1 cell
76
Double Cell Separation
5Ghz channels must be separated by at least 2 cells
77
Switch Density
WAPs need to be connected to a switch, so there needs to be enough switches in the area they're deployed to accommodate the switch connections
78
CSMA/CA
Carrier Sense Multiple Access / with Collison Avoidance
Avoids collisions, but no detection. For Wireless Transmission
79
CSMA/CD
Carrier Sense Multiple Access / with Collision Detection
For Wired Transmission
80
Antennas
Omnidirectional
Directional
Unidirectional
High Gain
81
Omnidirectional Antenna
Transmits in all directions / Radiates in all directions
Normal WAPS
Dipole Antenna
82
Directional Antenna
Provides coverage in a specific angle, adjustable
Typically increase range by around 2-3 times
Focused area or medium range point to point
Patch Antenna
83
Unidirectional Antenna
Focuses the power in a specific direction with a narrow path
Long range point to point
Yagi Antenna
84
High Gain Antenna
Range boosting antenna, larger antennas
With directional option sometimes incorporates a disk
Could be any antenna just at a large scale
85
Modulation Methods
FHSS (Frequency Hopping Speed Spectrum)
DSSS (direction Sequence Spread Spectrum)
OFDM (Orthogonal Frequency Division Multiplexing)
QPSK/QAM (Quadrature Phase-shift Keying
Quadrature Amplitude Modulation)
86
FHSS
FHSS (Frequency Hopping Speed Spectrum)
Pre-a (base 802.11)
Not used anymore
87
DSSS
DSSS (direction Sequence Spread Spectrum)
Modulation/Spectrum Frequency:
Humps on X-Y access, staying positive
88
OFDM
Used for all modern devices for high speed
Modulation/Spectrum Frequency:
Ovals along X, Y axis and goes negative on each
Larger, longer, when closer to 0 on both axises
89
QPSK/QAM
Quadrature Phase-shift Keying
Quadrature Amplitude Modulation
90
Attenuate
Whenever a signal goes through a wall it's going to have way less power when it comes out the other side of the wall. Shortens the range of your AP
91
Interference
RFI (Radio Frequency Interference)
Physical structure Interference
92
RFI
Radio Frequency Interference
When similar frequencies or channels are used in close proximity
Sources: Microwave ovens, cordless phones, Bluetooth, neighboring wireless LANS, other radio frequency emitting devices
93
Physical Structure Interference
Physical structures can attenuate and reflect the signal
Different building materials cause different levels of attenuation
94
Encryption Standards
WEP (Wired Equivalent Policy)
WPA (Wifi Protected Access)
WPA2 (Wifi Protected Access v2)
WPA3 (Wifi Protected Access v3)
95
WEP
(Wired Equivalent Policy)
Uses 4 different keys with Rc4 encryption
Inherent security flaws
Very easy to crack
96
WPA
Wifi Protected Access
TKIP (Temporal Key Integrity Protocol)
PSK (Pre-shared key)
WPA Enterprise Autnetication
Can be cracked, easier if simple 8 character password used
97
TKIP
Temporal Key Integrity Protocol
98
PSK
Pre-shared key
99
WPA2
Wifi Protected Access v2
AES Encryption (Advanced Encryption Standard)
PSK (Pre-shared key)
WPA Enterprise Authentication
100
WPA3
Wifi Protected Access v3
Strongest wireless encryption standard
101
Basic WLAN Threats
War Driving and War Chalking
WEP/WPRA/WPS attacks
Rogue AP/Evil Twin
102
War Driving and War Chalking
Driving around to identify wireless networks that can be accessed
Uses standardized symbols to convey the wifi details in public view
Open Node, Closed Node, WEP Node
103
Open Node
ssid at the top
)(
bandwidth below
104
Closed Node
ssid at top
O
bandwidth below
105
WEP Node
sside on left, access contact on right
circle with a w inside
(w)
bandwidth below
106
WEP/WPA/WPS attacks
Software utilities for cracking WEP crack, WPA PSK Crack, WPS (wireless Protected Setup)
107
WPS
Wireless Protected Setup
PIN can be easily brute forced
No one should use WPS as it's very insecure
108
Rogue AP / Evil Twin
An device is made to mimc a corporate AP an d mimic coporate SSID
Users may connect to the bad SSID without knowing it and then the bad guy gets all that information. Can be a WAP or home wireless router
109
Security Measures
Disable SSID Broadcast
MAC Address filtering
Client Isolation
Network Authentication
110
Disable SSID Broadcast
Prevents SSID from showing, but doesn't prevent the network from being found (nothing can prevent the network from being found)
111
MAC Address Filtering
Create a list of permitted or denied MAC addresses
Only approved MAC addresses get access
Good when only specific devices need access
112
Client Isolation
Public wireless SSIDs are normally a single broadcast domain
Any connected host can see and hear other connected hosts
Modern APs can create an isolated network that is only between the AP and the client itself which provides security for any connected HOST
113
Network Authentication
By using external authentication servers we can require usernames and passwords to access the wireless network in addition tot he regular PSK
802.11x w/ EAP, Radius, LDAP, etc.)
114
Unified Communications
Combination of VoIP, video, fax, chat/messaging etc. all into a single unified system
UC Devices
UC Servers
UC Gateway
115
Signaling
SIP (session initiation protocol)
H.323
MGCP (Media Gateway Control Protocol)
116
Codecs
is how our voice is actually modulated onto the wire. Each different codec will require larger amounts of bandwidth
117
SIP
session initiation protocol
Phone uses SIP to signal that it wants to make a phone call, sends to the call control server (VoIP) then the call control server will use signaling to initiate the phone call with the dissonant and after that the phones can actually talk to each other
TCP 5060 and 5061
118
H. 323
Signaling is for setting up the call. We use signaling for setting up the call but also we have signaling between/into our voice gateways and from our voice gateway to the PSTN. Signaling is used all throughout and between every single UC device
TCP 1720
119
MGCP
Media Gateway Control Protocol
Cisco Proprietary. We can use MGCP to set up a cisco voice gateway and we would use that MGCP protocol to communicate from the cisco voice gateway to the cisco call control server
UDP 2427 and 2727
120
RTP
Real-Time Transport Protocol
Used to have the voice go from point A to point B; it's what transports the audio or video
121
QoS
Allows us to manage and control the bandwidth usage and traffic priority on a network
122
QoS Tags
Markings applied to packets or Frames that allow network devices to classify traffic and apply QoS Standards
DSCP (Differentiated Services Code Point)
COS (Class of Service)
123
DSCP
Differentiated Services Code Point
Layer 3 QoS tagging, Defined in the IP Packet Header
Used with Routers only
124
COS
Class of Service
Layer 2 Qos tagging. Defined in the Ethernet Frame Header
Used with Switches only
125
Traffic Shaping
is a QoS term for controlling the bandwidth used by different applications and protocols.
Uses QoS technologies like DSCP and COS
126
Virtualization
Use a single physical machine's hardware to run multiple virtual machines within it
Uses the systems hardware
Better use of hardware resources
Power saving / reduced footprint
Recovery
Flexibility
Researching (sandbox)
127
Type 1 Hypervisor
Bare Metal Virtualization software
Accessed directly
VM Ware vSphere /ESXI
Microsoft Hyper V
Citrix Xen Server
Installed directly on a bare metal server
128
Type 2 Hypervisor
Hosted Virtualization software
Installed on a host OS, accessed through application
VMWare Workstation / Fusion
Oracle Virtual Box
Parralells (Mac os)
129
Virtual Switch
Virtual Switch for networking with virtual machines
130
Virtual NIC
Virtual NIC
131
VDI
Virtual Desktop Infrastructure
Virtualization of desktops / operating systems that run in the data center
Endpoints such as thin clients access their vm via the network
Any computer can be used in the virtual desktop infrastructure
131
Virtual Router
Virtual Router
131
Virutal Firewall
Virtual Firewall
131
Server Virtualization
Consolidation of servers into less hardware, creating virtual servers.
Physical to Virtual migration akak P to V
131
Thin Client
End points that access their vm via the network
They have a base OS on them, users access the network with these to access the "actual" computer
131
Public Cloud Computing
All about accessing services and resources from a remote data center and only paying for what you use
131
Data Center & CLoud
Data centers benefit from virtualization because of the ability to run more services and software in a smaller footprint
132
Benefits of Virtualization
Easier to manage
Cost SAvings
Run all servers in smaller fotprint
users less power
uses less hardware
133
IAAS
Infrastructure as a service
Complete hosted infrastructure in the cloud which provides access to networking features, computing hardware for desktops and servers, storage space, and internet access all as a service (pay for what you use)
Amazon Web Services
Azure
SaaS can be built on PaaS and PaaS can be built on IaaS
134
SaaS
Software as a Service
Hosted software solutions and services that are normally licensed on a subscription basis. Some is free, like Gmail
Paid: Microsoft O365
Drop Box
SaaS can be built on PaaS and PaaS can be built on IaaS
135
PaaS
Platform as a Service
Everything needed for setting up a web application in the cloud is provided as a hosted service. This allows software companies and developers to build applications without having to worry about anything else.
Servers, storage, OS, and databases are maintained by the provider
Amazon AWS
Heroku
SaaS can be built on PaaS and PaaS can be built on IaaS
136
Cloud Deplyment Models
Public Cloud,
Private Cloud,
Hybrid Cloud,
Community Cloud
137
Public Cloud
Everything needed to run the network and application is fully deployed in the cloud
138
Private Cloud
An "on premise" cloud, meaing the entire network, virtualization tech, servers and applications are deployed on premise, inside a company's data center
139
Hybrid Cloud
In order to be a true Hybrid Cloud the public and private clouds need to be connected to each other (through VPN)
With connectivity between the clouds, the resources can be shared between them
140
Community Cloud
The entire infrastructure is shared between multiple organizations. It could be hosted publicly, privately, or as a Hybrid, and the costs are shared among the community.
The organizations that are part of the community usually have similar privacy, security, performance, and compliance requirements
141
Storage Networking
Two types of network storage
NAS (Network Attached storage)
SAN (Storage Area Network)
142
NAS
Network Attached Storage
Network storage hardware that attach directly to the LAN
As LAN speeds become faster and faster we are seeing more enterprise grade NAS devices that support and certified for virtualized environments
Cheaper solution for smaller networks and home storage
143
SAN
Storage Area Networks
Networking of a SAN is separated from the LAN
Provides dedicated high speed networking between high end server architectures and an array of storage normally employing dedicated SAN switches
Often used for virtualized environments because they require good storage, speed, reliability and dr capabilities
144
vSAN
Virtual Storage Area Network
Technology created by VMWare that pools storage components from across the network. No need for a storage network or external arrays which reduces SAN cost and administrative overhead
Can use things like NAS as part of its storage pool
145
Storage Technologies
iSCSI (Internet Small Computer System Interface)
Fiber Channel
FCoE (Fiber Channel over Ethernet)
146
iSCSI
Internet Small Computer System Interface
Storage networking technology for SCSI based storage arrays. An iSCSI NIC maps a SCSI commander to TCP/IP so they work directly with TCP/IP based networks
147
Fiber Channel
Storage networking technology that runs at data rates up to 128Gbps
Normally used with Fiber Channel switches to build Storage Area Network
148
FCoE
Fiber Channel over Ethernet
A storage networking protocol that enables Fiber Channel traffic across Ethernet infrastructure
149
Jumbo Frames
Any frame larger than 1500 Bytes
Increased throughput when configured correctly, however, if configured incorrectly there can be MTU mismatches across the network and can cause problems
Recommended to enable Jumbo Frames to increase network throughput when a 10GbE or greater connection is used to the storage device
To enable Jumbo Frames on an ethernet network the MTU (Maximum Transmission Unit) needs to be adjusted to something greater than 1500 Bytes (usually 9000 Bytes)
150
MTU
Maximum transmission unit
151
