Meaning and purpose of QUIC protocol in networking

The QUIC protocol is an experimental option that one day might replace UDP and TCP. The digital world continually refines its internal operations. Usually, outdated practices’ abandonment attempts to pursue more clean-cut, optimized, and rapid response time. The QUIC protocol is no different in this sense. It represents an innovative approach, combining the best features of TCP, TLS, and UDP. This relatively new protocol aims to improve speed and reduce the packet transport delay. Let’s review this Google initiative and its calculated impact on networking as we know it.

What is the QUIC protocol?

The QUIC protocol (Quick UDP Internet Connection) is Google’s measure employed as a means for speeding up online activities. A more technical description would indicate QUIC as an encrypted transport layer network protocol. The introduction of QUIC aimed to release a more performance-centric protocol, encompassing HTTP/2, UDP, TCP, and TLS technologies. Officially, Google consulted IERF (Internet Engineering Task Force) in 2015, proposing QUIC as the new standard. One year later, Google released HTTP-over-QUIC. Now, IETF plans to officially base the HTTP/3 on QUIC, revolutionizing connections in the process.

The name QUIC protocol might be unfamiliar to the general public. No surprise there, as its integration does not move at a fast pace. According to statistics from W3Techs, only 1.2% of websites supported this protocol in 2018. In 2020, the QUIC application grew to 4.8% of sites supporting it. However, what started as a Google’s initiative, will be standardized by the IERF. So, the architecture behind networking might change significantly, and the web communities need to prepare for this refinement.

QUIC protocol is better: but why?

The dilemma between UDP and TCP has existed for decades. While UDP operations are lightweight, it is more prone to errors and inaccuracies. Hence, UDP is the preferred option for performance-sensitive applications when error correction is not a priority. TCP focuses on the perfect delivery of data packets. It communicates with the receiving server to guarantee that information arrives in its full and correct form. Gaming services that value quick response time typically apply UDP, white the web generally accepts TCP.

The QUIC protocol stands in between TCP and UDP, incorporating features from both to generate a novel approach to networking. According to Google, QUIC can speed the page load time by about 3% in its search engine. QUIC could have an even more striking effect on less polished and speed-optimized environments. In simpler terms, QUIC protocol delivers UDP-like speed while offering TCP-like protection for web traffic.

Microsoft has also recognized its benefits. The tech-giant has publicly released its in-house MsQuic library for managing network traffic occurring via the QUIC protocol. In Google’s case, it pushes the protocol’s integration even further. According to their blogpost, QUIC protocol reduces YouTube rebuffer time by more than 9% and significantly increases user throughput on desktop and mobile devices.

Benefits of using QUIC protocol

  • Low-latency connections. QUIC protocol significantly improves response time and speeds up connections. TCP needs to go through vigorous negotiation, known as the handshake, to verify client and server sessions. QUIC reduces the time spent communicating by conducting a single handshake. Usually, the connection can begin three times faster. In Uber’s report, the company reflected on the impressive reduction of tail-end latencies.
  • Efficient connection change. The technology marks each QUIC connection with a 64-bit ID. If clients unexpectedly change their IP addresses, the connection remains viable. In other words, the former connection ID resumes with the new IP address without any additional disruptions. When is this relevant? Well, one of the standard connection migrations occurs when users switch between Wi-Fi and cellular networks.
  • Clever packet loss management. QUIC protocol fixes the TCP problem when the system delays packets due to incomplete or lost packets. The performance suffers when disruptions with accurate transmission occur. QUIC permits packets to travel independently, without relying on others. Hence, re-delivery of packages happens much more efficiently.

Drawbacks of QUIC protocol

  • Not universal speed improvements. While evidence supports QUIC protocol as a more performance-centric protocol, it is not applicable in all scenarios. Some sources highlight its little to no positive effect on massive volumes of data in very high bandwidth networks. So, QUIC might not be the universal protocol for any occasion.
  • Throttling incoming UDP packets. QUIC protocol operates on top of UDP. Hence, what happens when networks throttle UDP packet speed? It would make sense to switch to TCP to enjoy a high-speed performance. Since QUIC relies on UDP, it passes through when throttled, but more sluggishly. The solution here would require an automatic shift to TCP in case of throttling.
  • Easy to develop, but not that popular. Since the QUIC protocol works at the application level, it is relatively simple to enhance. However, its integration is still in progress. Besides tech-giants experimenting with the protocol, only a small portion of the web uses it. Additionally, firewalls or other security mechanisms might not support it. Since firewalls could perform incomplete or flawed web traffic filtering, red-flagged connections could occur.

If you are uncomfortable with the QUIC protocol, you can disable it in Chrome. Type “chrome://flags/” as a regular URL into your Chrome browser. Then, find the “Experimental QUIC protocol” section and disable it. Atlas VPN can help you balance security and performance. How? Well, it encrypts web traffic automatically, making it nearly impossible for anyone to snoop or modify it. So, you won’t have to worry about having your communications or actions compromised. Also, it might solve throttling problems, giving you better performance.


John C.

John C.


Tags: tcp udp tls