DMT Consultant Interview Questions and Answers

The OSI (Open Systems Interconnection) model consists of 7 layers that define the functions of a network.

• Physical layer - deals with physical connections and signals (e.g. Ethernet cables)

• Data link layer - responsible for node-to-node communication (e.g. MAC addresses)

• Network layer - handles routing and forwarding of data packets (e.g. IP addresses)

• Transport layer - ensures end-to-end communication (e.g. TCP/UDP)

• Sessio...read more

Private IP address ranges are reserved for use within private networks and are not routable on the public internet.

• Private IP address ranges include 10.0.0.0 to 10.255.255.255, 172.16.0.0 to 172.31.255.255, and 192.168.0.0 to 192.168.255.255

• These addresses are commonly used in home, office, and corporate networks to allow devices to communicate with each other within the same network

• Private IP addresses are not unique ...read more

RFC 1918 refers to a set of IP address ranges reserved for private networks.

• RFC 1918 defines three blocks of IP addresses that are reserved for private networks: 10.0.0.0 - 10.255.255.255, 172.16.0.0 - 172.31.255.255, and 192.168.0.0 - 192.168.255.255

• These private IP addresses are not routable on the public internet and are commonly used within organizations for internal networks

• Using RFC 1918 addresses helps prevent c...read more

OSPF is a link-state routing protocol while EIGRP is a distance-vector routing protocol.

• OSPF uses Dijkstra algorithm to calculate the shortest path while EIGRP uses Diffusing Update Algorithm (DUAL)

• OSPF supports VLSM and CIDR while EIGRP does not

• OSPF is an open standard protocol while EIGRP is Cisco proprietary

• OSPF has a lower administrative distance (110) compared to EIGRP (90)

The types of BGP protocol include eBGP and iBGP.

• eBGP (External BGP) is used between different AS (Autonomous Systems)

• iBGP (Internal BGP) is used within the same AS

• eBGP is typically used for connecting to external networks, while iBGP is used for internal routing within the same network

IPsec is a protocol suite for securing Internet Protocol (IP) communications. IKE is a key management protocol used with IPsec.

• IPsec stands for Internet Protocol Security and is used to secure IP communications.

• It provides authentication, encryption, and key management for network traffic.

• IKE (Internet Key Exchange) is a key management protocol used with IPsec to establish security associations and negotiate cryptograp...read more

Main mode and aggressive mode are two different negotiation strategies used in business and consulting.

• Main mode is a collaborative negotiation approach where parties work together to find mutually beneficial solutions.

• Aggressive mode is a competitive negotiation approach where one party seeks to maximize their own gains at the expense of the other party.

• Main mode focuses on building relationships and trust, while aggr...read more

IPSec Parameters are settings used to configure and control the IPSec protocol for secure communication over a network.

• IPSec parameters include encryption algorithms such as AES, DES, and 3DES.

• Authentication methods like HMAC-SHA1, HMAC-MD5, and digital certificates are also part of IPSec parameters.

• Key exchange protocols such as IKEv1 and IKEv2 are used to establish secure communication channels.

• IPSec parameters also ...read more

Next Generation Firewall (NGFW) is a network security system that integrates intrusion prevention, application awareness, and other advanced features.

• NGFW combines traditional firewall capabilities with advanced security features like application control, intrusion prevention, and SSL inspection.

• It provides deeper visibility into network traffic and more granular control over applications and users.

• NGFWs can identify a...read more

NAT stands for Network Address Translation, a process used to modify network address information in packet headers while in transit.

• NAT allows multiple devices on a local network to share a single public IP address.

• There are different types of NAT such as Static NAT, Dynamic NAT, and PAT (Port Address Translation).

• NAT helps improve security by hiding internal IP addresses from external networks.

• Example: A home router u...read more