ICT Officer key topics and quick reference
An ICT officer needs a wide base of facts, because questions and real problems can come from any area. The reference tables on this page cover the essentials: the OSI model, common ports, special address ranges and key IT terms. The notes below explain how to review them efficiently and how the facts connect in the day-to-day running of an office.
How this guide was made
Written for this site with AI assistance, then checked automatically before publishing. The topic table, sample questions, worked examples and study plan are generated from this site’s question bank: each worked example is recalculated by separate code, and each sample answer says where it came from.
The guide deliberately states no salaries, grades, pass marks or exam dates. Those change, and they could not be checked here, so take them from the advert itself.
This site is independent and is not affiliated with MIFOTRA or any employer.
Where to spend your study time
The suggested emphasis reflects what this position works with day to day. It is a study guide, not a published exam blueprint.
| Area | Suggested emphasis | Questions in the bank | Practise |
|---|---|---|---|
| IT fundamentals and support practice | 21% | 484 | Hardware & OS |
| Hardware and operating systems | 21% | 961 | Hardware & OS |
| Networking fundamentals | 21% | 2,636 | Networking |
| Public service, customer care and policy | 21% | 20 | MIFOTRA ICT Officer |
| Cybersecurity | 14% | 541 | Security |
A little every day
Broad knowledge fades quickly without review. Spend ten minutes a day on one table: test yourself before reading, then check. Rotate through the tables across the week, and return to any facts you missed. This steady approach suits the breadth of an ICT officer test better than cramming.
Quick reference
Ports worth knowing by heart
| Service | Port | Transport |
|---|---|---|
| FTP data | 20 | TCP |
| FTP control | 21 | TCP |
| SSH (and SFTP, which runs over it) | 22 | TCP |
| Telnet | 23 | TCP |
| SMTP | 25 | TCP |
| DNS | 53 | TCP and UDP |
| DHCP server | 67 | UDP |
| DHCP client | 68 | UDP |
| TFTP | 69 | UDP |
| HTTP | 80 | TCP |
| Kerberos | 88 | TCP and UDP |
| POP3 | 110 | TCP |
| NTP | 123 | UDP |
| NetBIOS name service | 137 | UDP |
| NetBIOS session | 139 | TCP |
| IMAP | 143 | TCP |
| SNMP | 161 | UDP |
| SNMP trap | 162 | UDP |
| LDAP | 389 | TCP |
| HTTPS | 443 | TCP |
| SMB over TCP | 445 | TCP |
| SMTPS | 465 | TCP |
| Syslog | 514 | UDP |
| SMTP submission | 587 | TCP |
| LDAPS | 636 | TCP |
| IMAPS | 993 | TCP |
| POP3S | 995 | TCP |
| MSSQL | 1433 | TCP |
| Oracle DB | 1521 | TCP |
| MySQL | 3306 | TCP |
| RDP | 3389 | TCP |
| PostgreSQL | 5432 | TCP |
| VNC | 5900 | TCP |
| HTTP alternate | 8080 | TCP |
Special IPv4 address ranges
| Range | Purpose |
|---|---|
| 10.0.0.0/8 | Private addressing (RFC 1918) |
| 172.16.0.0/12 | Private addressing (RFC 1918): 172.16.0.0 to 172.31.255.255 |
| 192.168.0.0/16 | Private addressing (RFC 1918) |
| 100.64.0.0/10 | Carrier-grade NAT shared space (RFC 6598) |
| 127.0.0.0/8 | Loopback |
| 169.254.0.0/16 | Link-local (APIPA): a host that failed to get a DHCP lease |
The OSI model
| Layer | Name | What happens here | Examples |
|---|---|---|---|
| 7 | Application | Services the user’s software talks to | HTTP, DNS, SMTP, SNMP |
| 6 | Presentation | Data formatting, encoding and encryption | Character encoding, TLS |
| 5 | Session | Opening, maintaining and closing sessions | Session setup and teardown |
| 4 | Transport | End-to-end delivery, ports, reliability | TCP, UDP |
| 3 | Network | Logical addressing and routing between networks | IPv4, IPv6, ICMP; routers |
| 2 | Data link | Frames and physical (MAC) addressing on one link | Ethernet, 802.11; switches |
| 1 | Physical | Signals on the medium | Copper, fibre, radio; connectors |
Information Technology terms
| Term | Meaning |
|---|---|
| Asset register | A record of the organisation’s equipment and its details |
| Backup | A copy of data kept so it can be restored after loss |
| Change management | The controlled process for approving and recording system changes |
| DHCP | The protocol that automatically assigns IP configuration to clients |
| DNS | The system translating domain names into IP addresses |
| Incident | An unplanned interruption or reduction in quality of a service |
| Problem | The underlying cause of one or more incidents |
| RPO | The maximum data loss, in time, that a recovery plan accepts |
| RTO | The target time within which a service must be restored |
| SLA | An agreement defining the service level a provider commits to |
Connecting the facts to an office
Picture a small office when you study. Staff computers get private addresses from the router using DHCP, find websites using DNS, and reach the internet through NAT on the router. Email uses specific ports, remote support uses others, and a problem at one OSI layer looks different from a problem at another. Linking each fact to that picture makes it easier to recall under pressure.
Know these without hesitation
- Which OSI layer switches and routers mainly work at.
- What a 169.254 address and a 192.168 address each tell you.
- The ports for HTTPS, SSH, DNS, SMTP and RDP.
- The difference between a virus, a worm and ransomware.
- What multi-factor authentication adds to a password.
Common questions
Why does an ICT officer need the OSI model?
It gives a structured way to troubleshoot and explain problems, from a loose cable at the physical layer to a misconfigured application at the top.
How much should I memorise from the terms table?
Aim to explain each term in a sentence with an example. Understanding lasts longer than memorised definitions.
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