NETWORKING USE CASES - CHAPTER 4

Software-defined networking (SDN)

• bypasses limitations of physical architecture associated with traditional networks by combining network and application services

• adds dynamic capabilities to network; reduces IT costs via cloud architecture

Application layer (SDN)

top of SDN stack; load balancers, firewalls, intrusion detection, and other network applications in place of physical appliances

Control layer (SDN)

where SDN controller is; controller is software to manage policies and flow of traffic throughout network

Infrastructure layer (SDN)

physical switch devices define traffic routing and network topology

Management plane (SDN)

manges and monitors processes across all layers of network stack

Software-defined wide-area network (SD-WAN)

• extension of SDN

• virtual WAN architecture that uses software to manage connectivity, devices, and services

• can make changes in network based on current operations

Multi-Protocol Label Switching (MPLS for SD-WAN)

switching mechanism that forwards data packets based on labels, not just IP, when it arrives at MPLS network

Application-aware (SD-WAN)

has ability to ID, classify, and prioritize network traffic based on specific apps or services being used to improve network efficiency and security

Characteristics of SD-WAN

centralized control, dynamic path selection, transport independence, improved application performance, scalable

Virtual Extensible Local-Area Network (VXLAN)

• extension of VLAN by creating logical layer 2 networks over layer 3 infrastructure

• has scalability, flexibility over any IP-based network infrastructure, can provide logical isolation between virtual networks

VXLAN Network Identifier (VNI for VXLAN)

24 bit ID that identifies a VXLAN segment

VXLAN Tunnel Endpoint (VTEP for VXLAN)

device that encapsulates/decapsulates VXLAN packets

Data Center Interconnect (DCI for VXLAN)

what connects multiple datacenters together in VXLAN

Zero trust Architecture (ZTA)

• security framework that assumes no implicit trust within the network

• “never trust, always verify”

• continuous verification and authentication, least privilege access, continuous monitoring, encryption and data protection

Secure Access Secure Edge (SASE) / Security Service Edge (SSE)

• concept/architecture that combines network security functions with WAN capabilities to give secure, scalable access to cloud apps and resources

• lets organizations secure and optimize access to apps, data, and services regardless of user location or device type

Infrastructure as Code (IaC)

managing computing infrastructure using code, scripts, and files; offers consistency, speed, version control, and automation

Double colon in IPv6

shorthand for string of consecutive groups of 0s; appears only once;

formula for double colon in IPv6

(8 - visible blocks) * 16

Unicast IPv6 Address

specifies single interface; data packet sent from host directly to destination

Global unicast address (IPv6)

IPv4 public addresses that are routable and travel throughout network

Link-Local Address (IPv6)

• private network address designed for use on single local network

• automatically configured and required on all IPv6 interfaces

any address starting with fe80::

Site-Local Address (IPv6)

same as IPv4 private address space; doesn’t interfere with global unicast addresses; not automatically configured

Stateless configuration (IPv6)

IP autoconfiguration where admins don’t have to manually input configuration info

Stateful configuration (IPv6)

devices obtain address info from a server

Classful address (IPv6)

address falls into 1 of 5 IPv4 classes

Classless address (IPv6)

uses CIDR notation

Neighbor Discovery Protocol (NDP)

operates at network layer; responsible for autoconfiguring node addresses, discovering other nodes on link, determining addresses of other nodes, detecting duplicate addresses

Compatibility requirements (IPv6)

regarding tunneling mechanisms, dual-stack implementations, and NAT64 translation

NAT64 for IPv6

translation mechanism used to communicate between IPv6 only and IPv4 only devices by mapping IPv6 addresses to IPv4 addresses and vice versa