The Quick UDP Internet Connections (QUIC) protocol provides the same level of security as TLS/SSL but delivers lower connection and transmission latency. If you want to improve content delivery efficiency and ensure data transmission security, enable QUIC.
HTTP/3 and QUIC
What is HTTP/3?
HTTP/3 is the third version of the HTTP protocol, which uses QUIC as the underlying transmission protocol instead of Transmission Control Protocol (TCP) and Transport Layer Security (TLS). HTTP/3 retains many features of HTTP/2, such as header compression and multiplexing, and can better handle network congestion to reduce access latency.
What is QUIC?
QUIC is an experimental transport layer network protocol that provides the same security capabilities as TLS/SSL and reduces connection and transmission latency. QUIC is developed based on UDP and has an excellent performance when network connections are weak. When packet loss and network latency issues are severe, QUIC can still ensure service availability. QUIC can implement different congestion control algorithms for applications, regardless of the operating system or kernel that is used. Compared with TCP, QUIC supports flexible changes based on business requirements. QUIC is a suitable alternative when TCP optimization encounters bottlenecks.
Alibaba Cloud CDN supports QUIC that is implemented at Layer 7.
QUIC types
Alibaba Cloud CDN supports IETF QUIC and Google QUIC (gQUIC). Supported versions of gQUIC are Q39, Q43, and Q46.
IETF QUIC is a standard Internet protocol.
IETF QUIC is compatible with gQUIC versions G39, Q43, and Q46. We recommend that you use IETF QUIC.
Client requirements
QUIC has the following requirements for clients:
If you use Google Chrome, you can send QUIC requests to Alibaba Cloud CDN since Alibaba Cloud CDN supports HTTP/3.
If you use a self-developed app, the app must be integrated with a network protocol library that supports QUIC, such as lsquic-client, Cronet, ngtcp2, or quiche.
How it works
The following figure shows how QUIC works with Alibaba Cloud CDN.
Billing rules
QUIC is a value-added service. You are charged based on the number of QUIC requests. For more information, visit the CDN pricing page.
Alibaba Cloud CDN identifies QUIC requests based on whether they are transmitted over UDP.
QUIC requests whose protocol header is HTTPS: Alibaba Cloud CDN identifies whether the request is a QUIC request. If so, you are charged for a QUIC request. If not, you are charged for an HTTPS request.
Billing method
Billable item | Billing rule | Billing method | Billing cycle |
Billing of QUIC requests for static content | Number of requests to the domain name + Number of loads of static resources that are associated with the domain name | Pay-as-you-go | You are charged on an hourly basis. Bills are issued approximately 3 to 4 hours after the end of each billing cycle. |
Enable QUIC
Log on to the Alibaba Cloud CDN console.
In the left-side navigation pane, click Domain Names.
On the Domain Names page, find the domain name that you want to manage and click Manage in the Actions column.
In the left-side navigation tree, click QUIC Protocol, and turn on QUIC Protocol.
How to identify QUIC requests
In the following example, Google Chrome is used to show how to identify QUIC requests.
Procedure: Right-click a blank space on a web page and choose . If the value in the Protocol column of a request is h3-29, the request is a QUIC request.
If the Protocol column is not displayed, refresh the page, right-click a row, and then choose .
The following figure shows that the Protocol column displays h3-29, which indicates that the request is a QUIC request.
