Professional Knowledge - Information Technology (IT Officer)
Professional Knowledge is the scoring core of the IT Officer paper: it tests IT fundamentals plus how a bank actually runs technology. Expect DBMS, networking, operating systems, software engineering and information security, with a banking-technology flavour such as core banking, payment systems and RBI IT guidance.
What to master
- DBMS: ACID properties; normal forms - 1NF atomic values, 2NF no partial dependency on part of a composite key, 3NF no transitive dependency, BCNF every determinant is a candidate key. Indexes speed reads but slow writes.
- Networking: OSI seven layers and their PDUs; TCP versus UDP; well-known ports 80, 443, 21, 22, 53; private ranges 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16.
- Security: symmetric (AES) versus asymmetric (RSA); hashing (SHA-256) is one-way; a digital signature is a hash encrypted with the sender's private key, giving integrity, authentication and non-repudiation but not confidentiality.
- Banking technology: ISO 8583 for card and ATM messages, SWIFT MT for cross-border payments, NPCI-run UPI, IMPS and NEFT, core banking with a disaster-recovery site, the RBI Cyber Security Framework (2016), and IT Act 2000 sections 66, 66C and 66D.
Worked example
How many usable hosts does 172.16.0.0/22 provide? A /22 leaves 32 − 22 = 10 host bits, so usable hosts = 2^10 − 2 = 1022. The third-octet block size is 256 − 252 = 4, giving mask 255.255.252.0. Usable range 172.16.0.1 to 172.16.3.254, broadcast 172.16.3.255.
Traps
Assuming a /24 when the prefix is /22; forgetting to subtract 2 addresses; swapping IDS (detects) with IPS (blocks); claiming a digital signature encrypts the whole message; confusing 2NF with 3NF.