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1. Introduction

This section will gives brief description and history of past and current (2018) improvement and innovation of networking infrastructure and system. Be the first person to share your experience you see and work at this point of time.

2. Standards

Analyze a scenario and determine the corresponding OSI layer.

Layer 1 – Physical

Layer 2 – Data link

Layer 3 – Network

Layer 4 – Transport

Layer 5 – Session

Layer 6 – Presentation

Layer 7 – Application

3 Media

Install and properly terminate various cable types and connectors using appropriate tools

Copper cables

Shielded vs unshielded

CAT3, CAT5, CAT5e, CAT6, CAT6a

PVC vs plenum

RG-59

RG-6

Straight-through vs crossover vs rollover

Copper connectors

RJ-11

RJ-45

RJ-48C

DB-9/RS-232

DB-25

UTP coupler

BNC coupler

BNC

F-connector

110 block

66 block

Fiber cables

Single mode

Multimode

APC vs UPC

Fiber connectors

ST

SC

LC

MTRJ

FC

Fiber coupler

Media converters

Single mode fiber to Ethernet

Multimode fiber to Ethernet

Fiber to coaxial

Single mode to multimode fiber

Tools

Cable crimpers

Punch down tool

Wire strippers

Snips

OTDR

Cable certifier

Given a scenario, deploy the appropriate wired connectivity standard

Wiring standards

EIA/TIA 568A/568B

Given a scenario, troubleshoot and resolve common copper cable issues

Shorts

Opens

Incorrect termination (mismatched standards)

Straight-through

Crossover

Cross-talk

Near end

Far end

EMI/RFI

Distance limitations

Attenuation/Db loss

Bad connector

Bad wiring

Split pairs

Tx/Rx reverse

Cable placement

Bad SFP/GBIC - cable or transceiver

Given a scenario, troubleshoot and resolve common fiber cable issues

Attenuation/Db loss

SFP/GBIC - cable mismatch

Bad SFP/GBIC - cable or transceiver

Wavelength mismatch

Fiber type mismatch

Dirty connectors

Connector mismatch

Bend radius limitations

Distance limitations

Given a scenario, install and configure equipment in the appropriate location using best practices

Intermediate distribution frame

Main distribution frame

Cable management

Patch panels

Power management

Power converters

Circuits

UPS

Inverters

Power redundancy

Device placement

Air flow

Cable trays

Rack systems

Server rail racks

Two-post racks

Four-post racks

Free-standing racks

Labeling

Port labeling

System labeling

Circuit labeling

Naming conventions

Patch panel labeling

Rack monitoring

Rack security

4 Wireless

Explain the functions and applications of various network devices

· Router

· Switch

· Multilayer switch

· Firewall

· HIDS

· IDS/IPS

· Access point (wireless/wired)

· Content filter

· Load balancer

· Hub

· Analog modem

· Packet shaper

· VPN concentrator

Given a set of requirements, implement a basic network

· List of requirements

· Device types/requirements

· Environment limitations

· Equipment limitations

· Compatibility requirements

· Wired/wireless considerations

· Security considerations

5 Devices

Given a scenario, deploy the appropriate wired connectivity standard

· Ethernet standards

· 10BaseT

· 100BaseT

· 1000BaseT

· 1000BaseTX

· 10GBaseT

· 100BaseFX

· 10Base2

· 10GBaseSR

· 10GBaseER

· 10GBaseSW

· IEEE 1905.1-2013

· Ethernet over HDMI

· Ethernet over power line

· Given a scenario, implement and configure the appropriate addressing schema

· MAC addressing

· Explain the basics of network theory and concepts

· Numbering systems

· Binary

· Hexadecimal

· Octal

· Broadband/base band

· Bit rates vs baud rate

· Sampling size

· CDMA

· CSMA/CD and CSMA/CA

· Carrier detect/sense

· Wavelength

· Collision

6 IP Addressing

Given a scenario, implement and configure the appropriate addressing schema

· IPv6

· Auto-configuration

· EUI 64

· DHCP6

· Link local

· Address structure

· Address compression

· Tunneling 6to4, 4to6

· Teredo, miredo

· IPv4

· Address structure

· Subnetting

· APIPA

· Classful A, B, C, D

· Classless

· Private vs public

· NAT/PAT

· Multicast

· Unicast

· Broadcast

· Broadcast domains vs collision domains

7 Switching

Given a scenario, configure a switch using proper features

· PoE and PoE+ (802.3af, 802.3at)

· Managed vs unmanaged

· Default gateway

· Spanning tree (802.1d)/rapid spanning tree (802.1w)

· Switch management

· User/passwords

· AAA configuration

· Console

· Virtual terminals

· In-band/Out-of-band management

· VLAN

· Native VLAN/Default VLAN

· VTP

· Flooding

· Forwarding/blocking

· Filtering

· Interface configuration

· Trunking/802.1q

· Tag vs untag VLANs

· Port bonding (LACP)

· Port mirroring (local vs remote)

· Speed and duplexing

· IP address assignment

· VLAN assignment

8 Routing

Explain the basics of routing concepts and protocols

· Loopback interface

· Routing loops

· Routing tables

· Static vs dynamic routes

· Default route

· Distance vector routing protocols

· RIPv2

· Hybrid routing protocols

· BGP

· Link state routing protocols

· OSPF

· IS-IS

· Interior vs exterior gateway routing protocols

· Autonomous system numbers

· Route redistribution

· High availability

· VRRP

· Virtual IP

· HSRP

· Route aggregation

· Routing metrics

· Hop counts

· MTU, bandwidth

· Costs

· Latency

· Administrative distance

· SPB

9 Network Services

Install and configure the following networking services/applications

· DHCP

· Static vs dynamic IP addressing

· Reservations

· Scopes

· Leases

· Options (DNS servers, suffixes)

· IP helper/DHCP relay

· DNS

· DNS servers

· DNS records (A, MX, AAAA, CNAME, PTR)

· Dynamic DNS

· Proxy/reverse proxy

· NAT

· PAT

· SNAT

· DNAT

· Port forwarding

· Compare and contrast the following ports and protocols

· 80 HTTP

· 443 HTTPS

· 137-139 NetBIOS

· 110 POP

· 143 IMAP

· 25 SMTP

· 5060/5061 SIP

· 2427/2727 MGCP

· 5004/5005 RTP

· 1720 H.323

· TCP

· Connection-oriented

· UDP

· Connectionless

· Given a scenario, configure and apply the appropriate ports and protocols

· 20,21 FTP

· 161 SNMP

· 22 SSH

· 23 Telnet

· 53 DNS

· 67,68 DHCP

· 69 TFTP

· 445 SMB

· 3389 RDP

10 Wide Area Network

Explain the characteristics and benefits of various WAN technologies

· Fiber

· SONET

· DWDM

· CWDM

· Frame relay

· Satellite

· Broadband cable

· DSL/ADSL

· ISDN

· ATM

· PPP/Multilink PPP

· MPLS

· GSM/CDMA

· LTE/4G

· HSPA+

· 3G

· Edge

· Dialup

· WiMAX

· Metro-Ethernet

· Leased lines

· T-1

· T-3

· E-1

· E-3

· OC3

· OC12

· Circuit switch vs packet switch

· Given a scenario, deploy the appropriate wired connectivity standard

· Broadband standards

· DOCSIS

· Given a scenario, install and configure a basic firewall

· Types of firewalls

· Host-based

· Network-based

· Software vs hardware

· Application aware/context aware

· Small office/home office firewall

· Stateful vs stateless inspection

· UTM

· Settings/techniques

· ACL

· Virtual wire vs routed

· DMZ

· Implicit deny

· Block/allow

· Outbound traffic

· Inbound traffic

· Firewall placement

· Internal/external

· Explain the purpose of various network access control models

· 802.1x

· Posture assessment

· Guest network

· Persistent vs non-persistent agents

· Quarantine network

· Edge vs access control

· Compare and contrast the use of networking services and applications

· VPN

· Site to site/host to site/host to host

· Protocols

· IPsec

· GRE

· SSL VPN

· PTP/PPTP

· TACACS/RADIUS

· RAS

· Web services

· Unified voice services

· Network controllers

· Identify the basics elements of unified communication technologies

· VoIP

· Video

· Real time services

· Presence

· Multicast vs unicast

· QoS

· DSCP

· COS

· Devices

· UC servers

· UC devices

· UC gateways

· Given a scenario, troubleshoot and resolve common WAN issues

· Loss of internet connectivity

· Interface errors

· Split horizon

· DNS issues

· Interference

· Router configurations

· Customer premise equipment

· Smart jack/NIU

· Demarc

· Loopback

· CSU/DSU

· Copper line drivers/repeaters

· Company security policy

· Throttling

· Blocking

· Fair access policy/utilization limits

· Satellite issues

· Latency

11 Security

Compare and contrast risk related concepts

· Disaster recovery

· Business continuity

· Battery backups/UPS

· First responders

· Data breach

· End user awareness and training

· Single point of failure

· Critical nodes

· Critical assets

· Redundancy

· Adherence to standards and policies

· Vulnerability scanning

· Penetration testing

· Compare and contrast common network vulnerabilities and threats

· Attacks/threats

· Denial of service

· Distributed DoS

· Botnet

· Traffic spike

· Coordinated attack

· Reflective/amplified

· DNS

· NTP

· Smurfing

· Friendly/unintentional DoS

· Physical attack

· Permanent DoS

· ARP cache poisoning

· Packet/protocol abuse

· Spoofing

· Wireless

· Evil twin

· Rogue AP

· War driving

· War chalking

· Bluejacking

· Bluesnarfing

· WPA/WEP/WPS attacks

· Brute force

· Session hijacking

· Social engineering

· Man-in-the-middle

· VLAN hopping

· Compromised system

· Effect of malware on the network

· Insider threat/malicious employee

· Zero day attacks

· Vulnerabilities

· Unnecessary running services

· Open ports

· Unpatched/legacy systems

· Unencrypted channels

· Clear text credentials

· Unsecure protocols

· TELNET

· HTTP

· SLIP

· FTP

· TFTP

· SNMPv1 and SNMPv2

· TEMPEST/RF emanation

· Given a scenario, implement network hardening techniques

· Anti-malware software

· Host-based

· Cloud/server-based

· Network-based

· Switch port security

· DHCP snooping

· ARP inspection

· MAC address filtering

· VLAN assignments

· Network segmentation

· Security policies

· Disable unneeded network services

· Use secure protocols

· SSH

· SNMPv3

· TLS/SSL

· SFTP

· HTTPS

· IPsec

· Access lists

· Web/content filtering

· Port filtering

· IP filtering

· Implicit deny

· Wireless security

· WEP

· WPA/WPA2

· Enterprise

· Personal

· TKIP/AES

· 802.1x

· TLS/TTLS

· MAC filtering

· User authentication

· CHAP/MSCHAP

· PAP

· EAP

· Kerberos

· Multifactor authentication

· Two-factor authentication

· Single sign-on

· Hashes

· MD5

· SHA

· Compare and contrast physical security controls

· Mantraps

· Network closets

· Video monitoring

· IP cameras/CCTVs

· Door access controls

· Proximity readers/key fob

· Biometrics

· Keypad/cipher locks

· Security guard

· Summarize basic forensic concepts

· First responder

· Secure the area

· Escalate when necessary

· Document the scene

· eDiscovery

· Evidence/data collection

· Chain of custody

· Data transport

· Forensics report

· Legal hold

· Given a scenario, troubleshoot and resolve common security issues

· Misconfigured firewall

· Misconfigured ACLs/applications

· Malware

· Denial of service

· Open/closed ports

· ICMP related issues

· Ping of death

· Unreachable default gateway

· Unpatched firmware/OSs

· Malicious users

· Trusted

· Untrusted users

· Packet sniffing

· Authentication issues

· TACACS/RADIUS misconfigurations

· Default passwords/settings

· Improper access/backdoor access

· ARP issues

· Banner grabbing/OUI

· Domain/local group configurations

· Jamming

12 Management

Given a scenario, implement the appropriate policies or procedures

· Security policies

· Consent to monitoring

· Network policies

· Acceptable use policy

· Standard business documents

· SLA

· MOU

· MSA

· SOW

· Given a scenario, use appropriate resources to support configuration management

· Archives/backups

· Baselines

· On-boarding and off-boarding of mobile devices

· NAC

· Documentation

· Network diagrams (logical/physical)

· Asset management

· IP address utilization

· Vendor documentation

· Internal operating procedures/policies/standards

· Explain the basics of change management procedures

· Document reason for a change

· Change request

· Configuration procedures

· Rollback process

· Potential impact

· Notification

· Approval process

· Maintenance window

· Authorized downtime

· Notification of change

· Documentation

· Network configurations

· Additions to network

· Physical location changes

· Explain the importance of implementing network segmentation

· SCADA systems/Industrial control systems

· Legacy systems

· Separate private/public networks

· Honeypot/honeynet

· Testing lab

· Load balancing

· Performance optimization

· Security

· Compliance

· Given a scenario, install and apply patches and updates

· OS updates

· Firmware updates

· Driver updates

· Feature changes/updates

· Major vs minor updates

· Vulnerability patches

· Upgrading vs downgrading

· Configuration backup

· Summarize safety practices

· Electrical safety

· Grounding

· ESD

· Static

· Installation safety

· Lifting equipment

· Rack installation

· Placement

· Tool safety

· MSDS

· Emergency procedures

· Building layout

· Fire escape plan

· Safety/emergency exits

· Fail open/fail close

· Emergency alert system

· Fire suppression systems

· HVAC

· Compare and contrast technologies that support cloud and virtualization

· Virtualization

· Virtual switches

· Virtual routers

· Virtual firewall

· Virtual vs physical NICs

· Software defined networking

· Storage area network

· iSCSI

· Jumbo frame

· Fibre Channel

· Network attached storage

· Cloud concepts

· Public IaaS, SaaS, PaaS

· Private IaaS, SaaS, PaaS

· Hybrid IaaS, SaaS, PaaS

· Community IaaS, SaaS, PaaS

13 Monitoring and Troubleshooting

Given a scenario, use appropriate monitoring tools

· Packet/network analyzer

· Interface monitoring tools

· Port scanner

· Top talkers/listeners

· SNMP management software

· Trap

· Get

· Walk

· MIBS

· Alerts

· Email

· SMS

· Packet flow monitoring

· SYSLOG

· SIEM

· Environmental monitoring tools

· Temperature

· Humidity

· Power monitoring tools

· Wireless survey tools

· Wireless analyzers

· Given a scenario, analyze metrics and reports from monitoring and tracking performance tools

· Baseline

· Bottleneck

· Log management

· Graphing

· Utilization

· Bandwidth

· Storage

· Network device CPU

· Network device memory

· Wireless channel utilization

· Link status

· Interface monitoring

· Errors

· Utilization

· Discards

· Packet drops

· Interface resets

· Speed and duplex

· Given a scenario, implement the following network troubleshooting methodology

· Identify the problem

· Gather information

· Duplicate the problem, if possible

· Question users

· Identify symptoms

· Determine if anything has changed

· Approach multiple problems individually

· Establish a theory of probable cause

· Question the obvious

· Consider multiple approaches

· Top-to-bottom/bottom-to-top OSI model

· Divide and conquer

· Test the theory to determine cause

· Once theory is confirmed, determine next steps to resolve problem

· If theory is not confirmed, re-establish new theory or escalate

· Establish a plan of action to resolve the problem and identify potential effects

· Implement the solution or escalate as necessary

· Verify full system functionality and if applicable implement preventative measures

· Document findings, actions, and outcomes

· Given a scenario, troubleshoot and resolve common network issues

· Incorrect IP configuration/default gateway

· Broadcast storms/switching loop

· Duplicate IP

· Speed and duplex mismatch

· End-to-end connectivity

· Incorrect VLAN assignment

· Hardware failure

· Misconfigured DHCP

· Misconfigured DNS

· Incorrect interface/interface misconfiguration

· Cable placement

· Interface errors

· Simultaneous wired/wireless connections

· Discovering neighboring devices/nodes

· Power failure/power anomalies

· MTU/MTU black hole

· Missing IP routes

· NIC teaming misconfiguration

· Active-active vs active-passive

· Multicast vs broadcast