{"id":9859,"date":"2018-12-17T12:00:27","date_gmt":"2018-12-17T20:00:27","guid":{"rendered":"https:\/\/www.privateinternetaccess.com\/blog\/?p=9859"},"modified":"2022-11-19T17:42:05","modified_gmt":"2022-11-20T01:42:05","slug":"tcp-vs-udp-understanding-the-difference","status":"publish","type":"post","link":"https:\/\/www.privateinternetaccess.com\/blog\/tcp-vs-udp-understanding-the-difference\/","title":{"rendered":"TCP vs UDP: Protocols, Ports, and Practical Applications"},"content":{"rendered":"\n

When and how to use protocols, and with which ports, can be extremely confusing if you aren\u2019t tech-savvy. Luckily, most apps and online services are preset to use certain protocols<\/strong> already. Some apps, like VoIP services, establish connections with TCP, but use UDP to transfer communications. Others, like VPNs, give you an option of which protocol and port you\u2019d like to use.\u00a0<\/p>\n\n\n\n

Either way, all the choices can be confusing. So, it\u2019s important to know the basics before making any configurations to an app\u2019s default settings<\/strong>. Both protocols have their strong points, whether you go with the reliability and stability of TCP, or the speed and efficiency of UDP. Our guide is here to ensure you make the right choice for you.\u00a0<\/p>\n\n\n\n

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TCP & UDP At A Glance<\/strong><\/h2>\n\n\n\n

TCP and UDP are both transport layer protocols. The transport layer controls all point-to-point communications<\/strong> in a standard open systems interconnection (OSI) model, which contains the 7 layers required for technological devices to communicate effectively over a network.\u00a0<\/p>\n\n\n\n

I won\u2019t get too technical. Let\u2019s take a look at the basics<\/strong> before we dive into definitions and details.\u00a0<\/p>\n\n\n\n\n \n \n
TCP & UDP Basics<\/strong><\/th><\/tr><\/thead>\n
Comunication Method<\/td>\n Overhead<\/td>\n Header Length<\/td>\n Use Examples<\/td>\n Stream Type<\/td>\n <\/tr>\n
TCP<\/td>\n Host-to-Host<\/td>\n Low<\/td>\n 20-60 Bytes Variable<\/td>\n HTTPS, HTTP, FTP, & Telenet <\/td>\n Byte<\/td> \n <\/tr>\n
UDP<\/td>\n Process-to-Process<\/td>\n Very Low<\/td>\n 8 Bytes Fixed<\/td>\n DNS, VOIP, DHCP & SMTP <\/td>\n Message<\/td>\n<\/tr><\/tbody><\/table>\n\n\n\n

Advantages and Disadvantages of TCP\u00a0<\/strong><\/h3>\n\n\n\n

Transmission control protocol (TCP) is a host-to-host connection-based protocol<\/strong>, so it needs an established connection before it can transmit data. For the protocol to work, it must create, maintain, and close a connection<\/strong>. Once a source transmits a packet, the destination device must confirm receipt before any additional packets are sent.\u00a0<\/p>\n\n\n\n

TCP protocols use in-depth error-checking methods to provide flow and congestion control<\/strong>. Byte streams help maintain sequence order, and the use of data sequencing allows you to retransmit lost packets before the next packet is sent.\u00a0<\/p>\n\n\n\n

Longer header lengths and error-checking and acknowledgement requirements make TCP a bit heavier than UDP. The upside is it means reliable, secure communications. It never<\/strong> sends your data to the wrong destination or leaves your connection open<\/strong>.<\/p>\n\n\n\n

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UDP Pros and Cons<\/strong><\/h3>\n\n\n\n

User datagram protocol (UDP) is a communications-based protocol and operates process-to-process<\/strong>, so it isn\u2019t reliant on connection agreements and doesn\u2019t require packet acknowledgement. This protocol can send data packets before the destination device agrees, and can continue to send them one after another without confirmed delivery. It doesn\u2019t rely on opening, maintaining, or closing connections, and error-checking isn\u2019t required<\/strong>. UDP only performs basic checksums for error-checking if any.<\/p>\n\n\n\n

UDP has a significantly lower overhead and a fixed header length, making it faster and more efficient<\/strong> than TCP. Its lightweight transmissions are excellent for situations where transmission speed trumps accuracy. It\u2019s also bandwidth intensive to endure packet loss and readily supports broadcast and multicast transmissions.<\/p>\n\n\n\n

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Protocols vs Ports<\/strong><\/h3>\n\n\n\n

Ports are the channels used for communications, while protocols determine how those communications take place. Basically, ports are the river, and protocols are the vessel you use to navigate it<\/strong>. Both TCP and UDP ports provide data security, but TCP offers greater structure and reliability, while UDP offers speed and efficiency.<\/p>\n\n\n\n

Other protocols can also be used with TCP and UDP ports, including OpenVPN, WireGuard\u00ae, HTTP, and SMTP. For instance, PIA uses OpenVPN over UDP by default, but you\u2019re welcome to change your protocol and port options at any time. We offer OpenVPN and WireGuard\u00ae protocols, as well as IPSec for our iPhone VPN<\/a> client.<\/p>\n\n\n\n

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