Quick UDP Internet Protocol (QUIC) is a combination of (TCP+TLS+HTTP/2) protocols implemented on UDP. The QUIC transport protocol multiplexes the connections between two endpoints using UDP. Also when compared to other protocols, QUIC provides a high-performance in terms of security, fast delivery of traffic, and lower latency.

A QUIC bridge is configured in a Citrix ADC appliance for load balancing QUIC traffic between a QUIC client and QUIC back-end server. The QUIC bridge enables you to have persistent QUIC connections between client and server if there is a NAT rebinding or a connection migration. This configuration however does not process data. It is used only for load balancing of QUIC traffic through the Citrix ADC appliance.

QUIC packets contain connection ID to allow endpoints to associate the packets with different address or 4-tuple to the same connection. The connection ID contains the details of the server ID that are shared to the Citrix ADC appliance and to the back end servers. The Citrix ADC appliance extracts the connection ID details of the server ID and sends the traffic back to the back end server. The connection IDs are in protected packets that makes the connections robust in the event of connection migration.


The back end servers must have support to encode server ID in QUIC connection ID.

Benefits of QUIC bridge

QUIC bridge for the Citrix ADC appliance is preferred for the following reasons:

  • No expensive crypto operations.
  • Stateless routing is possible (no 4-tuple based load balancing).