Networking Concepts (1.0)

Network Functions Virtualization (NFV)

Improves Network flexibility and scalability by virtualizing network functions

reduces number of required physical devices

Supports both 2.4 and 5Ghz frequency bands

802.11n

802.11ac

802.11ax

Twinaxial cables

Offers high speed data transfer with low latency over short distances

Class A address

supports small number of LARGE networks

Application Aware Networking

Enhances Performance of business critical applications by prioritizing their network traffic. Ensures allocation of necessary bandwidth and lower latency.

Key function of Presentation layer (layer 6)

Data encryption and decryption

Internet gateway in a cloud environment

Directs outgoing traffic from instances to the internet

Directs incoming traffic from the internet to instances

An extension of SSH

SFTP

What transport layer protocol does TFTP use?

UDP

provides connection-less communication to transfer files with minimal overhead

Window Size

A TCP feature

used to control the flow of data to prevent network congestion

Determines the amount of data that can be sent before receiving an ACK from the receiver

RFC1918

Consist of address ranges in an internal network to help conserve public IP addresses

Allows organizations to use private IP addresses for internal communications

reduces need to allocate public IPs for every device

Class B IP

most likely to be used by a medium sized enterprise network

Content Delivery Network (CDN)

Improves website performance by caching content closer to end users

Sends users to closest server

Packet Scheduling

A QoS technique used to ensure that high priority traffic is sent before lower priority traffic.

Determines the order in which packets are transmitted based on their priority levels

MOST significant challenge in satellite communication systems

High latency due to signal travel distance

Key advantage of class C IP

Large number of small networks

Transport agnostic

Commonly used to simplify the management of the transport layer

enables seamless integration and operation across various transport protocols

Secure Access Service Edge (SASE)

Provides scalable and centralized security controls via Cloud based security services

Combines network security function with WAN capabilities

simplifies management of security policies and configurations

Prefix length in an IP address

The portion of the address that specifies the network

What does IPsec commonly use for key exchange

Internet Key exchange (IKE)

Facilitates negotiation of security associations and keys for secure communication

primary function of SMB (server messages block)

to provide shared access to files and printers

802.3af

standard for power over ethernet (PoE) applications (not usable with IP phones)

provides less power than 802.3at

Access layer

responsible for connecting end devices to the network

provides initial entry points for devices (computers, printer, AP)

Variable Length Subnet masking (VLSM)

involves using different subnet masks within the same network to create subnets of varying sizes

optimizing IP allocation

Virtual Extensible LAN (VXLAN)

Increases VLAN capacity by allowing up to 16 million logical networks

overcomes limitation of traditional VLANs

Collapsed core network design

when the distribution layer and core layer are integrated together

streamlines network architecture by reducing number of layers

Class D IP address

specifically used in multicast groups

enables efficient distribution of data to multiple recipients

Data Center Interconnect (DCI)

used to connect multiple data centers

enables data replication, workload mobility, and disaster recovery

Layer 2 network diagram (data link)

useful for understanding the logical connections and data flow between devices in a network

MAC addresses and VANS

manages how data is transferred between devices on the same network segment

crucial for illustrating logical connections like MAC addresses and VLAN assignments

Most crucial component of SNMP

MIB

defines and organizes the data that can be managed on a network device

provides a hierarchical structure that specifies the variables (data) that SNMP can manage

DHCP relay

used to forward DHCP requests and responses between clients and a server on different subnets

allows DHCP services to extend across multiple subnets

Forward DNS zone

resolves domain names to IP addresses

Reverse DNS zone

maps IP addresses to domain names

Network Security List (NSL)

a set of rules that define network security policies for resources

These rules control the traffic allowed to and from network resources

ensures security compliance

Mutlicast Vs. Broadcast

Multicast sends data to a specific group of interested devices

Broadcast sends data to all devices in the network

Direct Attach Copper (DAC) cables

they include built in transceivers

makes them suitable for short distance connections within data centers and network racks

Class E IP

240.0.0.0 - 255.255.255.255

Reserved for experimental purposes

IPv6 length

128 bits

IPv4 length

32 bits

Layer 3 (network layer) diagram

most appropriate for visualizing IP routing and network layer protocols

responsible for routing packets across different networks and managing logical addressing (IP)

Hexadecimal

Used in IPv6

0-9 & A-F can be used in each octet

Fiber to the Premise (FTTP)

fiber cable runs directly to home or business

100% fiber connection and ultra fast

Fiber to the Curb (FTTCurb)

fiber cable is brought to distribution point (or curb) near premises

Remaining distance is covered by copper cables

high speeds but not as high as FTTP

Very high speed Digital Subscriber Line (VDSL)

Copper telephone lines for high speed internet

faster than ADSL | speeds up to 100mbps or higher

Asymmetric Digital Subscriber Line (ADSL)

Copper telephone lines but slower than VDSL

Speeds from 1-24mbps

higher attenuation as distance increases

Optical Network Terminal (ONT)

Converts fiber optical signals to electrical signals for homes or business

ultrafast broadband | 1gb or multi gb speeds

not affected by distance like copper

Virtual Private Cloud (VPC)

provides the functionalities for a VPN

allows you to securely isolate and manage your cloud resources (server, database, storage) with a high degree of control

Spine and leaf topology

2 layer network (not 3)

provides better support for east-west(within) traffic in data centers

Dense Wavelength Division Multiplexing (DWDM)

Allows a single fiber strand to carry a high number of channels

supports greater number of channels (20,40, 80, or 160)

Ideal for long distance fiber transmissions and high capacity needs

Bidirectional Wavelength Division Multiplexing (BiDi)

provides the ability for fiber to retrieve and receive over the same strand of fiber

does not support a high number of channels or cater to long-distance transmissions

Coarse Wavelength Division Multiplexing (CWDM)

supports up to 16 wavelengths

typically used for shorter distances in fiber connections and fewer channels than DWDM

Redirection in Neighbor Discovery Protocol

Allows routers to inform hosts of a more efficient route to a specific destination

can help optimize network traffic by ensuring that packets take the most efficient path

reduces latency and congestion on certain network segments

NAS

provides file level storage

not for use of data intensive applications

SAN

supports integration of different types of storage technology (RAID and Tape libraries)

allows for use of a mix of high speed and low cost devices

Three-tier hierarchical model

provides scalability allowing for expansion in the access and distribution layers without major redesigns

collapsed core model

simplifies network

limits scalability as company grows (potentially requiring significant redesign)

VXLAN network identifier (VNI)

used to differentiate between different VXLAN overlay networks

24-bit identifier

Variable length subnet masking (VLSM)

allows subnets of multiple sizes to be created within a larger network

optimizes use of IP address spaces by tailoring subnet sizes to specific needs

Dynamic inventories

simplifies network management and reduces manual effort

automatically discovers and updates network devices

eliminate the need for manual inventory management

NAT gateway

allows resources within virtual private cloud (VPC) to access the internet without directly being exposed to the internet

Security Service Edge (SSE)

leverages cloud based security services to protect distributed users and devices

NAT64

allows IPv6 only devices to access IPv4 resources by translating IPv6 packets to IPv4 and vice versa

Connectionless protocols

ICMP, UDP, IP, and IPX

Site to site VPN

connects entire networks to each other securely over the internet

advantages of anycast

efficient routing of data

reduced latency

improved fault tolerance

allows multiple, goegraphicallly dispersed servers to share the same IP address

Layer 7, 6, and 5

where data is transmitted in the OSI model

Layer 4

where data is encapsulated into segments the OSI model

layer 3

where segments are turned into packets in the OSI model

Layer 2

Where packets are turned into frames in the OSI model

Layer 1

where frames are turned into bits in the OSI model

Infrastructure as a service (Iaas)

cloud computing service that offers essential compute, storage, and networking resources on demand, on a pay-as-you-go basis.

(useful for instances in which you need to restore server images from cloud provider in case of disaster or failure)

Spine and leaf network architecture

each leaf switch is connected to every spine switch

802.3at

A standard for IP phones because it provides more power for PoE devices

IPsec

commonly used to establish secure VPN tunnels

provides encryption and authentication to ensure secure communication over the internet