Networking fundamentals required for ITOM

[KhasimKhanP]

Hi folks,

Which networking fundamentals are essential before starting in IT Operations Management (ITOM)?

[Chavan AP]

@KhasimKhanP 

Networking Fundamentals for ITOM - Detailed Overview

Core Networking Concepts

TCP/IP Protocol Suite:

• Understanding IPv4/IPv6 addressing and subnetting
• OSI and TCP/IP model layers
• How packets flow through networks
• Port numbers and common services (HTTP:80, HTTPS:443, SSH:22, etc.)

Network Infrastructure:

• Switching vs. routing concepts
• VLANs and network segmentation
• Network topologies (star, mesh, hybrid)
• Load balancers and their role in application delivery

DNS and Name Resolution:

• How DNS queries work (A, AAAA, PTR, CNAME records)
• Forward and reverse DNS lookups
• DNS hierarchy and delegation
• Impact on service discovery and monitoring

ITOM-Specific Networking Knowledge

SNMP (Simple Network Management Protocol):

• SNMP versions (v1, v2c, v3) and security implications
• OIDs (Object Identifiers) and MIB (Management Information Base)
• SNMP traps vs. polling
• Community strings and authentication

Network Discovery Protocols:

• CDP (Cisco Discovery Protocol)
• LLDP (Link Layer Discovery Protocol)
• ARP tables for device relationships
• Network topology mapping through protocol data

Network Security Fundamentals:

• Firewall rules and access control lists
• Network segmentation and DMZ concepts
• VPN tunnels and secure communications
• Network access control (NAC) basics

ServiceNow ITOM Integration Points

Discovery Requirements:

• Network ranges and credentialed discovery
• Port requirements for different discovery types
• Proxy and MID server network considerations
• Firewall rules needed for discovery agents

Monitoring and Events:

• Network device monitoring via SNMP
• Synthetic transaction monitoring
• Network performance metrics collection
• Event correlation from network devices

Asset and Configuration Management:

• Network device CI relationships
• IP address management integration
• Network service dependencies
• Switch port and connection mapping

Practical Tools and Commands

Network Troubleshooting:

• ping, traceroute, nslookup/dig
• netstat, ss, lsof for connection analysis
• tcpdump/wireshark for packet analysis
• iptables/firewall rule verification

Network Scanning and Discovery:

• Nmap for port scanning and OS detection
• Network discovery tools (lansweeper, advanced IP scanner)
• SNMP walk utilities
• Network mapping tools

Advanced Concepts for ITOM

API and Automation:

• REST APIs for network device management
• NETCONF/YANG for configuration management
• Network automation frameworks
• Integration with orchestration tools

Cloud and Hybrid Networks:

• Software-defined networking (SDN) basics
• Cloud networking concepts (VPC, subnets, security groups)
• Hybrid cloud connectivity
• Container networking fundamentals

Performance and Capacity:

• Bandwidth measurement and analysis
• Network latency and jitter concepts
• Quality of Service (QoS) basics
• Network capacity planning principles

Common ITOM Use Cases

Service Mapping:

• Understanding application network flows
• Database connection tracking
• Load balancer configuration discovery
• Network service dependencies

Event Management:

• Network device alert correlation
• Threshold-based monitoring setup
• Network outage impact analysis
• Root cause analysis through network topology

This foundation enables effective use of ServiceNow Discovery, Service Mapping, Event Management, and other ITOM applications by providing the networking context needed to understand infrastructure relationships and dependencies.

Trainings- 

Complete trainigns- CIS CMDB, Service Mapping, Discovery, Event Mgmt

[Simon Hendery]

Hi @Chavan AP 

I think you used genAI to create this answer? Much of what you've posted is wrong.

[Pratiksha]

For Discovery

• IP Basics → IP ranges, subnetting, network classes.

• Networks → On-prem (servers, routers, switches) vs Cloud (AWS, Azure, GCP).

• Devices → Routers, switches, firewalls, servers, endpoints.

• Authentication → SNMP (network), WMI (Windows), SSH (Linux), APIs (cloud), Agent-based.

For Service Mapping

• Need above + server administration knowledge (Windows/Linux).

• Understanding of ports, protocols, app servers, and databases