Logical Topology Physical Topology
Logical topology = network flow
Physical topology = physical layout of the cabling
centralized management / administration
Peers share resources directly with others
PAN -> LAN -> CAN -> MAN -> WAN
PAN - Personal Area Network
LAN - Local Area Network
CAN - Campus Area Network
MAN - Metropolitan Area Network
WAN - Wide Area Network
The S in IOT stands for Security (... but there is no S in IOT !)
ex. wifi, bluetooth, RFID, NFC, IR, Z-Wave (home automation), ANT+ (sensors)...
OSI - Open System Interconnection (iso 7498)
OSI model = OSI stack
PDNTSPA = Please Do not Throw Sausage Pizza Away
| 7 layers | ||
|---|---|---|
| (1) | Physical | Bits |
| (2) | Data Link | Frames |
| (3) | Network | Packets |
| (4) | Transport | Segments |
| (5) | Session | Data |
| (6) | Presentation | Data |
| (7) | Application | Data |
Bits are transmitted
Includes Physical and Electrical network characteristics
ex. ethernet, fiber, copper, radio frequencies (wifi)
Bits -> Binary Bits
Transition Modulation: switching between 0 and 1
Wirering standards (PIN setup in the connector)
Crossover cable: 568A -> 568B
Straightforward cable or Patch cable: 568B -> 568B
Baseband, how can we get more of a limited network ? Multiplexing !
Multiplexing, simultaneous use of a Basenad Connection.
Physical Layer (1) - No Logic to it, no Intelligence to it
Layer 1 devices simply repeat whatever they're told
=> whatever comes in is going to come out
Layer 1 = dumb devices / simple repeaters
Packages data (bits) into frames and transmit those frames on the network while performing:
Physical addressing system of a device which operates on a logical topology
Every manufacturer assigns a unique 48 bits address to a Network Interface Card (NIC)
48 bits address - 12 digits hexadecimal numbers - each letter/number = 4 bits
ex. :
Layer 2 devices view network logically
whose turn it is to talk to and transmit so other devices aren't talking over each other
ex. classes: system of students raising their hands in turns to wait to speak
-> control of the information flow
Electronic mechanism to do the same thing: Logical Link Control (LLC)
provides connection services and ackwowledgment of receipt of messages
LLC is the most basic form of flow control
=> It limits the amount of data a sender can send at once and allow the receiver to keep from being overwhelmed
It provides basic error control functions:
Isochronous Mode
Network devices can use a common reference clock source and create time slots for retransmissions
Synchronous Mode
TCP/IP Model (OBJ. 1.1)
Data Transfer Over Networks (OBJ. 1.1)
|---|---|---|
|21|FTP|Fast Transfert Protocol|
Finding Open Ports (OBJ. 5.3)
IP Protocol Types (OBJ. 1.5)
Media and Cabling (OBJ. 1.3)
Copper Media (OBJ. 1.3 & 5.2)
Building a Cable (OBJ. 1.3)
Fiber Media (OBJ. 1.3)
Transceivers (OBJ. 1.3)
Cable Distribution (OBJ. 1.3)
Wiring a Network (OBJ. 1.3)
Testing the Network (OBJ. 5.2)
Ethernet Fundamentals (OBJ. 1.3, 2.3, & 5.5)
Network Infrastructure Devices (Overview) (OBJ. 2.1)
Hands-on with Devices (OBJ. 2.1)
Additional Ethernet Switch Features (OBJ. 2.3 & 4.4)
Spanning Tree Protocol (OBJ. 2.3 & 5.5)
Virtual Local Area Network (VLAN) (OBJ. 2.3)
Specialized Network Devices (OBJ. 2.1)
Other Devices (OBJ. 2.1)
IP Addressing (OBJ. 1.4)
IPv4 Addressing (OBJ. 1.4)
IPv4 Data Flows (OBJ. 1.4)
Assigning IP Addresses (OBJ. 1.4 & 1.6)
Computer Mathematics (OBJ. 1.4)
Subnetting (OBJ. 1.4)
Subnetting Practice (OBJ. 1.4)
Subnetting by Hand (OBJ. 1.4)
IPv6 Addressing (OBJ. 1.4)
IPv6 Data Flows (OBJ. 1.4)
Routing Fundamentals (OBJ. 2.2)
Routing Tables (OBJ. 2.2 & 5.5)
Routing Protocols (OBJ. 2.2)
Address Translation (NAT and PAT) (OBJ. 1.4)
Multicast Routing (OBJ. 1.4)
Network Services (OBJ. 1.6)
DHCP (OBJ. 1.6)
Hands-on with DHCP (OBJ. 1.6)
DNS (OBJ. 1.6)
Hands-on with DNS (OBJ. 1.6)
NTP (OBJ. 1.6)
Wide Area Networks (WAN) (OBJ. 1.2)
Wired WAN Connections (OBJ. 1.2)
Wireless WAN Connections (OBJ. 1.2 & 2.4)
WAN Technologies (Part 1) (OBJ. 1.2)
WAN Technologies (Part 2) (OBJ. 1.2)
Hands-on with WANs (OBJ. 1.2)
Other WAN Connections (OBJ.
Wireless Networking (WLAN) (OBJ. 2.1)
WLAN Service Sets (OBJ. 2.4 & 5.4)
Wireless Antennas (OBJ. 2.4 & 4.3)
Hands-on with Antennas (OBJ. 2.4 & 5.4)
Wireless Frequencies (OBJ. 2.4 & 5.4)
Wireless Security (OBJ. 2.4, 4.3, & 5.4)
Hands-on with Wireless (OBJ. 2.4 & 4.3)
When Security Fails (OBJ. 4.2 &
Cloud and the Datacenter (OBJ. 1.7 & 1.8)
Virtual Network Devices (OBJ. 1.2 & 1.7)
Voice Over IP (VoIP) (OBJ. 2.1)
Cloud Computing (OBJ. 1.8)
Cloud Concepts (OBJ. 1.8)
Virtualization and Cloud Computing (OBJ. 1.2)
Infrastructure as Code (OBJ. 1.8)
Connectivity Options (OBJ. 1.8)
Datacenter Architecture (OBJ. 1.7)
Network Security (OBJ. 4.1)
The CIA Triad (OBJ. 4.1)
Threats and Vulnerabilities (OBJ. 4.1)
Risk Management (OBJ. 4.1)
Security Principles (OBJ. 4.1)
Defense in Depth (OBJ. 4.1)
Multifactor Authentication (OBJ. 4.1 & 4.3)
Authentication Methods (OBJ. 4.1)
Network Access Protocols (OBJ. 4.1)
Network Access Control (OBJ. 4.1)
Physical Security (OBJ. 4.5)
Asset Disposal (OBJ. 4.5)
Network Attacks (OBJ. 4.2)
Denial of Service Attacks (OBJ. 4.2)
General Network Attacks (OBJ. 4.2)
Spoofing Attacks (OBJ. 4.2)
Malware (OBJ. 4.2)
Wireless Attacks (OBJ. 4.2)
Social Engineering Attacks (OBJ. 4.2)
Insider Threat (OBJ. 4.2)
Security Technologies
Firewalls (OBJ. 2.1, 4.1, & 4.3)
Hands-on with Firewalls (OBJ. 4.3)
Hands-on with Software Firewalls (OBJ. 4.3)
IDS and IPS (OBJ. 2.1)
Remote Access (OBJ. 4.4)
Virtual Private Networks (VPNs) (OBJ. 4.4)
IPSec (OBJ. 1.5)
Simple Network Management Protocol (OBJ. 3.1)
Network Logging (OBJ. 3.1)
SIEM (OBJ. 4.1)
Network Hardening (OBJ. 4.3)
Patch Management (OBJ. 4.3)
Password Security (OBJ. 4.3)
Unneeded Services (OBJ. 4.3)
Port Security and VLANs (OBJ. 4.3)
Inspection and Policing (OBJ. 4.3)
Securing SNMP (OBJ. 4.3)
Access Control Lists (OBJ. 4.3)
Wireless Security (OBJ. 4.3)
IoT Considerations (OBJ. 4.3)
Network Availability (OBJ. 2.2 & 3.3)
High Availability (OBJ. 3.3)
Designing Redundant Networks (OBJ. 3.3)
Recovery Sites (OBJ. 3.3)
Facilities Support (OBJ. 3.3)
Quality of Service (QoS) (OBJ. 2.2)
QoS Categorization (OBJ. 2.2)
QoS Mechanisms (OBJ. 2.2)
Network Policies (OBJ. 3.2)
Plans and Procedures (OBJ. 3.2)
Hardening and Security Policies (OBJ. 3.2)
Common Agreements (OBJ. 3.2)
Network Management (OBJ. 3.1 & 3.2)
Common Documentation (OBJ. 3.2)
Performance Metrics (OBJ. 3.1)
Sensors (OBJ. 3.1)
NetFlow Data (OBJ. 3.1)
Interface Statistics (OBJ. 3.1)
Environmental Sensors (OBJ. 3.1)
Network Troubleshooting Methodology (OBJ. 5.1)
Cable Review (OBJ. 5.2)
Cabling Tools (OBJ. 5.2)
Cable Signal Issues (OBJ. 5.2)
Copper Cable Issues (OBJ. 5.2)
Fiber Cable Issues (OBJ. 5.2)
Ethernet Issues (OBJ. 5.2)
Troubleshooting Wireless Networks (OBJ. 5.4)
Wireless Considerations (OBJ. 5.4)
Coverage and Interference (OBJ. 5.4)
Incorrect Configurations (OBJ. 5.4)
Captive Portal (OBJ. 5.4)
Network Tools and Commands (OBJ. 5.3)
Software Tools (OBJ. 5.3)
ping and traceroute (OBJ. 5.3)
ipconfig, ifconfig, and ip (OBJ. 5.3)
nslookup, dig, and hostname (OBJ. 5.3)
arp, route, nbtstat, netstat (OBJ. 5.3)
telnet, tcpdump, and nmap (OBJ. 5.3)
Network Platform Commands (OBJ. 5.3)
Troubleshooting Network Issues (OBJ. 5.5)
Collisions and Broadcast Storms (OBJ. 5.5)
Duplicate Addresses (OBJ. 5.5)
Routing Issues (OBJ. 5.5)
Loops (OBJ. 5.5)
DHCP Issues (OBJ. 5.5)
IP and VLAN Settings (OBJ. 5.5)
Firewall Issues (OBJ. 5.5)
DNS and NTP Issues (OBJ. 5.5)
Network Performance Issues (OBJ. 5.5)
Other Issues (OBJ. 5.5)