Internet Domain: TCP, UDP, SSL, and TLS
ssl://, tls://,
sslv2:// & sslv3://.
Note:
The sslv2:// and sslv3:// transports
are obsolete and should not be used. They are documented for
backward compatibility only.
Note:
If no transport is specified, tcp:// will be assumed.
127.0.0.1fe80::1www.example.comtcp://127.0.0.1tcp://fe80::1tcp://www.example.comudp://www.example.comssl://www.example.comtls://www.example.com
Internet Domain sockets expect a port number in addition
to a target address. In the case of fsockopen
this is specified in a second parameter and therefore does
not impact the formatting of transport URL. With
stream_socket_client and related functions
as with traditional URLs however, the port number is specified
as a suffix of the transport URL delimited by a colon.
tcp://127.0.0.1:80tcp://[fe80::1]:80tcp://www.example.com:80
Note:
IPv6 numeric addresses with port numbers
In the second example above, while the IPv4 and hostname
examples are left untouched apart from the addition of
their colon and portnumber, the IPv6 address is wrapped in
square brackets: [fe80::1]. This is to
distinguish between the colons used in an IPv6 address and
the colon used to delimit the portnumber.
The ssl:// and tls:// transports
(available only when openssl support is compiled into PHP) are extensions
of the tcp:// transport which include SSL encryption.
ssl:// will attempt to negotiate a secure SSL/TLS
connection depending on the capabilities and preferences of both the
client and the remote host. The actual protocols that may be used are
determined by the OpenSSL configuration and by any options provided
through stream_context_create, such as
ssl.crypto_method.
The SSLv2 and SSLv3 protocols are obsolete and insecure. Their use is
strongly discouraged and they are no longer enabled by default in
modern versions of PHP and OpenSSL.