AT&S Network Engineer L1 Interview Questions, Process, and Tips

VLAN stands for Virtual Local Area Network, used to segment a network into multiple isolated networks for security and performance purposes.

• VLANs allow for logical segmentation of a network, improving security and performance.

• Devices within the same VLAN can communicate with each other as if they were on the same physical network.

• VLANs are commonly used in enterprise networks to separate different departments or functi...read more

The ISO model is a conceptual framework that standardizes the functions of a telecommunication or computing system into seven layers.

• The ISO model stands for International Organization for Standardization model.

• It consists of seven layers: Physical, Data Link, Network, Transport, Session, Presentation, and Application.

• Each layer has specific functions and communicates with the adjacent layers for data transmission.

• For ...read more

Switching is the process of forwarding data packets between devices on the same network, while routing is the process of forwarding data packets between different networks.

• Switching operates at Layer 2 of the OSI model, using MAC addresses to forward packets within a network.

• Routing operates at Layer 3 of the OSI model, using IP addresses to forward packets between networks.

• Switches create broadcast domains, while rout...read more

Proxy is an intermediary server that separates end users from the websites they browse. DHCP is a network protocol that assigns IP addresses to devices.

• Proxy server acts as a middleman between a user and the internet, providing anonymity and security.

• DHCP dynamically assigns IP addresses to devices on a network, simplifying network administration.

• Proxy servers can be used to bypass content restrictions or improve netwo...read more

BGP stands for Border Gateway Protocol, used for routing between different autonomous systems on the internet.

• BGP is a standardized exterior gateway protocol used to exchange routing information between different autonomous systems (AS).

• It helps in determining the best path for data packets to travel between networks.

• BGP is crucial for ensuring efficient and reliable internet connectivity.

• It allows network administrato...read more

Routing protocols determine how data packets are forwarded across a network, while routed protocols define the format of the packets.

• Routing protocols are used by routers to determine the best path for forwarding data packets.

• Examples of routing protocols include RIP, OSPF, and BGP.

• Routed protocols are used to format the data packets themselves, such as IP or IPv6.

• Examples of routed protocols include TCP/IP, UDP, and I

OSPF, RIP, IGRP, and EIGRP are routing protocols used in networking to determine the best path for data packets to travel.

• OSPF (Open Shortest Path First) is a link-state routing protocol that uses Dijkstra's algorithm to calculate the shortest path.

• RIP (Routing Information Protocol) is a distance-vector routing protocol that uses hop count as a metric to determine the best path.

• IGRP (Interior Gateway Routing Protocol) ...read more

VLAN types include default, data, voice, management, and native VLANs.

• Default VLAN: VLAN 1 is the default VLAN on Cisco switches.

• Data VLAN: Used for data traffic.

• Voice VLAN: Used for voice traffic.

• Management VLAN: Used for managing network devices.

• Native VLAN: Untagged VLAN used for trunking.

Router commands are used to configure and manage routers in a network.

• show ip interface brief - displays a summary of the router's interfaces and their IP addresses

• show running-config - displays the current configuration of the router

• interface [interface name] - enters interface configuration mode for a specific interface

• ip route [destination network] [subnet mask] [next hop IP] - adds a static route to the routing tab

Subnet mask is a 32-bit number used to divide an IP address into network and host portions.

• Subnet mask is used to determine which part of an IP address is the network portion and which part is the host portion.

• There are different types of subnet masks such as Classful subnet masks, Classless subnet masks, and Variable Length Subnet Masks (VLSM).

• Examples of subnet masks include 255.255.255.0 (Class C), 255.255.0.0 (Clas