Networking Intermediate

What is MTU (Maximum Transmission Unit)?

The maximum size of a data packet that can be transmitted over a network without fragmentation.

MTU defines the largest packet size a network link can handle. Standard Ethernet MTU is 1500 bytes. Packets larger than MTU are either fragmented (split into smaller packets) or dropped if the Don't Fragment flag is set.

MTU mismatches cause connectivity issues — packets are silently dropped. Path MTU Discovery automatically finds the smallest MTU along a route. Jumbo frames (MTU 9000) improve performance on local networks. VPN and tunnel overhead may require reducing MTU.

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NAT (Network Address Translation)

A method of mapping private IP addresses to public IP addresses, allowing multiple devices to share a single public IP.

VPN (Virtual Private Network)

A technology that creates an encrypted tunnel between your device and a remote server, securing internet traffic.

A server that sits between clients and backend servers, forwarding client requests and returning server responses on their behalf.

DNS (Domain Name System)

A hierarchical naming system that translates human-readable domain names into IP addresses.

Two transport layer protocols: TCP provides reliable, ordered delivery while UDP provides fast, connectionless delivery without guarantees.

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Different types of DNS entries that map domain names to various information like IP addresses, mail servers, and verification strings.

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