IUP ITS flashcards

33 cards. Read the term and the definition here. The deck at the top of this page is optional.

Incident vs problem

An incident is an unplanned interruption or degradation restored as quickly as possible; a problem is the underlying cause investigated to prevent recurrence, often recorded as a known error with a workaround.

Priority calculation

Priority is derived from impact (how many users or services are affected) multiplied by urgency (how quickly business is harmed). The resulting matrix assigns P1 through P4 response targets.

SLA, OLA, UC

An SLA is an agreement with the customer, an OLA is an internal agreement between support teams, and an underpinning contract is with an external supplier. All three should align so internal targets support the customer promise.

MTTR and MTBF

Mean time to repair is total downtime divided by the number of incidents. Mean time between failures is total uptime divided by the number of failures. Availability equals MTBF divided by MTBF plus MTTR.

Change types

Standard changes are pre-approved and low risk; normal changes go through assessment and CAB approval; emergency changes use an expedited approval path. A change freeze suspends normal changes during critical periods.

OSI model layers

Seven layers from bottom: Physical, Data Link, Network, Transport, Session, Presentation, Application. Switches forward at layer 2, routers at layer 3, and firewalls commonly inspect layers 3 through 7.

Private IPv4 ranges

RFC 1918 ranges are 10.0.0.0/8, 172.16.0.0/12, and 192.168.0.0/16. They are not routable on the public internet and require NAT for external access. APIPA 169.254.0.0/16 indicates DHCP failure.

DHCP DORA process

The client broadcasts Discover, the server sends Offer, the client sends Request, and the server replies Acknowledge. The lease includes an IP address, subnet mask, default gateway, DNS servers, and a lease duration.

TCP three-way handshake

The client sends SYN, the server replies SYN-ACK, and the client sends ACK. This establishes a reliable, ordered connection. UDP skips the handshake and is used where latency matters more than guaranteed delivery.

VLAN and trunking

A VLAN is a layer-2 broadcast domain. Access ports carry one VLAN; trunk ports carry multiple VLANs using 802.1Q tags. Inter-VLAN traffic needs a router or layer-3 switch.

CIA triad

Confidentiality prevents unauthorized disclosure through encryption and access control. Integrity prevents unauthorized modification through hashing and signatures. Availability ensures timely access through redundancy, backups, and resilience.

Multi-factor authentication

MFA requires two or more different factor categories: something you know, something you have, or something you are. Two passwords are not MFA because they are the same category.

Symmetric vs asymmetric encryption

Symmetric encryption such as AES uses one shared key and is fast for bulk data. Asymmetric encryption such as RSA or ECC uses a public and private key pair, solving key exchange and enabling digital signatures.

Hashing and salting

A cryptographic hash such as SHA-256 is one-way and changes drastically if data is altered, so it detects tampering. A salt is random data added before hashing to defeat precomputed rainbow-table attacks on passwords.

Risk treatment options

Risk equals likelihood times impact. Treatment options are mitigate (reduce), transfer (insurance or contract), avoid (stop the activity), and accept (documented residual risk with management sign-off).

Incident response phases

The sequence is Preparation, Identification, Containment, Eradication, Recovery, and Lessons Learned. Containment limits spread before eradication removes the cause, and lessons learned feeds improvements back into preparation.

Linux file permissions

Permissions are read (4), write (2), and execute (1) for owner, group, and others. chmod 755 gives the owner rwx and group and others r-x. chown changes ownership and chgrp changes group.

Group Policy processing order

Group Policy Objects apply in the order Local, Site, Domain, then Organizational Unit. Later policies generally override earlier ones unless the setting is enforced, and inheritance can be blocked at an OU.

Backup types

A full backup copies all selected data. A differential copies changes since the last full. An incremental copies changes since the last backup of any type. Restoring an incremental set requires the full plus every incremental in order.

RAID levels

RAID 0 stripes for performance with no redundancy. RAID 1 mirrors. RAID 5 stripes with single parity and tolerates one disk failure. RAID 6 uses double parity. RAID 10 mirrors and stripes.

Hypervisor types

A Type 1 hypervisor runs directly on hardware, as with VMware ESXi or Microsoft Hyper-V, offering better performance and security. A Type 2 hypervisor runs on a host operating system, as with VirtualBox.

ERP and CRM

ERP integrates core back-office processes such as finance, human resources, and supply chain in one system. CRM manages customer-facing interactions including sales, service, and marketing. Both require data governance.

Database keys

A primary key uniquely identifies each row. A foreign key references a primary key in another table and enforces referential integrity. A composite key combines two or more columns to form a unique identifier.

ACID properties

Atomicity means all-or-nothing transactions. Consistency enforces valid state transitions. Isolation prevents concurrent transactions from interfering. Durability ensures committed data survives failure. These are core relational database guarantees.

RPO and RTO

Recovery point objective is the maximum acceptable data loss measured in time. Recovery time objective is the maximum acceptable service downtime. Both drive backup frequency and recovery architecture decisions.

Policy versus procedure

A policy states mandatory rules and intent. A standard specifies measurable requirements. A procedure gives step-by-step instructions. A guideline is recommended practice. Policy sits above standards, procedures, and guidelines.

ISO/IEC 27001

An international standard for establishing, operating, and continually improving an information security management system. Certification requires risk assessment, documented controls, internal audit, and management review.

Least privilege

Users and systems receive only the access needed for their tasks and only for as long as needed. It is a preventive control that limits blast radius and is verified through periodic access reviews.

GDPR breach notification

Under GDPR, a personal data breach likely to result in risk to individuals must be reported to the supervisory authority within 72 hours of awareness, and affected data subjects must be informed when risk is high.

Cloud service models

In IaaS the customer manages the operating system and above. In PaaS the provider manages the platform and the customer manages applications and data. In SaaS the customer manages mainly data and access.

Containers versus virtual machines

Containers share the host operating system kernel, so they start quickly and use fewer resources. Virtual machines each run a full guest operating system, giving stronger isolation at higher overhead.

Earned value formulas

Cost variance equals earned value minus actual cost. Schedule variance equals earned value minus planned value. Cost performance index equals earned value divided by actual cost. Values below 1.0 indicate over budget or behind schedule.

Critical path

The critical path is the longest sequence of dependent tasks through a project network. It determines the shortest possible project duration, and any delay on it delays the whole project unless compressed.