HTTP Capsule filter
Tunneling UDP datagrams over HTTP (see Proxying UDP in HTTP) requires an encapsulation mechanism to preserve the boundaries of the original datagram. This filter applies the HTTP Datagrams and the Capsule Protocol to downstream and upstream datagrams, so they are compliant with the Capsule Protocol.
Note
This filter must be used last in the UDP session filter chain, and should only be used when tunneling UDP over HTTP streams.
This filter should be configured with the type URL
type.googleapis.com/envoy.extensions.filters.udp.udp_proxy.session.http_capsule.v3.FilterConfig.