HTML and CSS Reference
In-Depth Information
Table 8-1.
Using Encrypted/Unencrypted WebSocket with Explicit and Transparent
Proxy Servers
Proxy
Server Type
WebSocket
Connection
Connection Result
Considerations
No proxy
Unencrypted and
Encrypted
Connection succeeds
WebSocket connections
succeed if there are no
network intermediaries
between the client and the
server.
Explicit
Unencrypted
Connection
succeeds*
An explicit proxy server
allows the CONNECT
method. The resulting
connection is non-secure.
*Only if the proxy
server correctly
ignores traffic after
the CONNECT
method
Explicit
Encrypted
Connection succeeds
An explicit proxy server
allows the CONNECT
method. The client sends the
TLS handshake, followed by
the WebSocket connection
upgrade handshake. After
this series of handshakes
succeeds, WebSocket traffic
can start flowing unimpeded
through the proxy server.
Transparent
Unencrypted
Connection fails
A well-behaved transparent
proxy server does not
understand the 101 response
code, and thus should cause
the WebSocket handshake to
fail almost immediately.
Transparent
Encrypted
Connection succeeds
Because the traffic is
encrypted, a transparent
proxy allows the connection
to succeed and the
WebSocket traffic to flow.
Proxies are often grouped into two categories: explicit and transparent proxies.
The proxy server is explicit when the browser is explicitly configured to use it. For explicit
proxies you have to provide your browser with the proxy's host name, port number, and
optionally user name and password. The proxy server is transparent when the browser is
not aware that the traffic is intercepted by a proxy.
