Endpoint Syntax
Ice uses endpoints for two similar but distinct purposes:
In a client context (that is, in a proxy), endpoints determine how Ice establishes a connection to a server.
In a server context (that is, in an object adapter's configuration), endpoints define the addresses and transport protocols over which new incoming connections are accepted.
Endpoint is an overloaded term - many things are “endpoints”. Think of an Ice endpoint as a “server address”. Not so coincidentally, that’s the term we’ve adopted for IceRPC.
This page presents the addressing component of endpoints, as well as the transport protocols and their options.
Endpoint List Syntax
Synopsis
endpoint : endpoint
Description
An endpoint list comprises one or more endpoints separated by a colon (:).
An endpoint has the following format:
transport option
transport can be any of the Ice transport protocols described on this page (tcp, ssl, udp etc.), or default. When default is used, it is replaced by the value of the Ice.Default.Protocol property (default protocol means default transport protocol). If an endpoint is malformed, or an unknown transport protocol is specified, the application receives a ParseException.
See Object Adapter Endpoints for examples.
IP Address Syntax
Synopsis
host : hostname | x.x.x.x | ":x:x:x:x:x:x:x"
Description
Ice supports Internet Protocol (IP) versions 4 and 6 in all language mappings.
Support for these transport protocols is configured using the properties Ice.IPv4 and Ice.IPv6 (both enabled by default).
In the endpoint descriptions below, the host parameter represents either a host name that is resolved via the Domain Name System (DNS), an IPv4 address in dotted quad notation, or an IPv6 address in 128-bit hexadecimal format and enclosed in double quotes. Due to limitation of the DNS infrastructure, host and domain names are restricted to the ASCII character set.
The presence (or absence) of the host parameter has a significant influence on the behavior of the Ice runtime. The table below describes these semantics:
Value | Client Semantics | Server Semantics |
|---|---|---|
None | If | If |
Host name | The host name is resolved via DNS. Outgoing connections are attempted to each address returned by the DNS query. |
You should avoid using DNS names in object adapter endpoints. The host name is resolved via DNS, and the object adapter listens on the network interfaces corresponding to each address returned by the DNS query. |
IPv4 address | An outgoing connection is attempted to the given address. | The object adapter listens on the network interface corresponding to the address. |
IPv6 address | An outgoing connection is attempted to the given address. | The object adapter listens on the network interface corresponding to the address. |
| A "wildcard" IPv4 address that causes Ice to try all local interfaces when establishing an outgoing connection. | The adapter listens on all IPv4 network interfaces (including the loopback interface), that is, binds to INADDR_ANY for IPv4. |
| A "wildcard" IPv6 address that causes Ice to try all local interfaces when establishing an outgoing connection. | Equivalent to * (see below). |
| Not supported in proxies. | The adapter listens on all network interfaces (including the loopback interface), that is, binds to INADDR_ANY for the enabled transport protocols (IPv4 and/or IPv6). |
When IPv4 and IPv6 are enabled, an object adapter endpoint that uses an IPv6 (or * wildcard) address can accept both IPv4 and IPv6 connections.
TCP Endpoint Syntax
Synopsis
tcp -h host -p port -t timeout -z --sourceAddress addr
Availability
The TCP transport protocol is a built-in transport protocol: it's always available.
Description
A tcp endpoint supports the following options:
Option | Description | Client Semantics | Server Semantics |
|---|---|---|---|
| Specifies the host name or IP address of the endpoint. If not specified, the value of | See IP Address Syntax. | |
| Specifies the port number of the endpoint. | Determines the port to which a connection attempt is made (required). | The port will be selected by the operating system if this option is not specified or |
| Specifies the endpoint timeout in milliseconds. | The value for Endpoint timeouts are deprecated. They have no effect as of Ice 3.8. | |
| Specifies bzip2 compression. | Determines whether requests are compressed during sending. | Determines whether compression is advertised in proxies created by the adapter. |
| Specifies the source address used by the connection. | The value for This option allows to specify the source address set in the IP packet. It doesn't necessarily imply that the operating system will use the network interface matching this IP address to send out the IP packet. | Not supported |
UDP Endpoint Syntax
Synopsis
udp -h host -p port -z --ttl TTL --interface INTF --sourceAddress addr
Availability
The UDP transport protocol is a built-in transport protocol that is always available.
Description
A udp endpoint supports either unicast or multicast delivery; the address resolved by host argument determines the delivery mode. To use multicast in IPv4, select an IP address in the range 233.0.0.0 to 239.255.255.255. In IPv6, use an address that begins with ff, such as ff01::1:1.
A udp endpoint supports the following options:
Option | Description | Client Semantics | Server Semantics |
|---|---|---|---|
| Specifies the host name or IP address of the endpoint. If not specified, the value of | See IP Address Syntax. | See IP Address Syntax. |
| Specifies the port number of the endpoint. | Determines the port to which datagrams are sent (required). | The port will be selected by the operating system if this option is not specified or port is zero. |
| Specifies bzip2 compression. | Determines whether requests are compressed during sending. | Determines whether compression is advertised in proxies created by the adapter. |
| Specifies the time-to-live (also known as "hops") of multicast messages. | Determines whether multicast messages are forwarded beyond the local network. If not specified, or the value of | N/A |
| Specifies the network interface or group for multicast messages (see below). | Selects the network interface for outgoing multicast messages. If not specified, multicast messages are sent using the default interface. | Selects the network interface to use when joining the multicast group. If set to * or not specified, the group is joined on all the local network interfaces. |
| Binds outgoing socket connections to the network interface associated with | The value for This option allows to specify the source address set in the IP packet. It doesn't necessarily imply that the operating system will use the network interface matching this IP address to send out the IP packet. This feature is not supported on Universal Windows (UWP). | Not supported |
Deprecated options
With the 1.0 encoding, UDP endpoints supported 2 additional options: the -e major.minor and -v major.minor options. These 2 options specified which encoding and protocol was supported by the endpoint. These two options are deprecated with the 1.1 encoding and are ignored (a deprecation warning will be emitted when parsed by the communicator stringToProxy method). The supported protocol and encoding is specified on the proxy with the 1.1 encoding.
Multicast Interfaces
When host denotes a multicast address, the --interface INTF option selects a particular network interface to be used for communication. The format of INTF depends on the language and IP version:
C++ and .NET
INTFcan be an interface name, such aseth0, or an IP address. If using IPv6, it can also be an interface index. Interface names on Windows may contain spaces, such asLocal Area Connection, therefore they must be enclosed in double quotes.Java
INTFcan be an interface name, such aseth0, or an IP address. On Windows, Java maps interface names to Unix-style nicknames.
SSL Endpoint Syntax
Synopsis
ssl -h host -p port -t timeout -z --sourceAddress addr
Description
An ssl endpoint supports the same options as for tcp endpoints.
WS Endpoint Syntax
Synopsis
ws -r resource -h host -p port -t timeout -z --sourceAddress addr
Description
A ws (WebSocket) endpoint supports all tcp endpoint options in addition to the following:
Option | Description | Client Semantics | Server Semantics |
|---|---|---|---|
| A URI specifying the resource associated with this endpoint. If not specified, the default value is | The value for | The web server configuration must direct the given |
WSS Endpoint Syntax
Synopsis
wss -r resource -h host -p port -t timeout -z --sourceAddress addr
Description
A wss (Secure WebSocket) endpoint supports all ssl endpoint options in addition to the following:
Option | Description | Client Semantics | Server Semantics |
|---|---|---|---|
| A URI specifying the resource associated with this endpoint. If not specified, the default value is | The value for | The web server configuration must direct the given |
Bluetooth Endpoint Syntax
Synopsis
bt -a addr -u uuid -c channel -t timeout -z --name namebts -a addr -u uuid -c channel -t timeout -z --name name
Availability
The Bluetooth transport protocol is provided by a separate IceBT plug-in.
Description
Support for Bluetooth endpoints is provided by the IceBT transport plug-in. The plug-in enables the bt transport protocol by default; if the IceSSL plug-in is also installed, IceBT enables the bts transport protocol as well. A Bluetooth endpoint supports the following options:
Option | Description | Client Semantics | Server Semantics |
|---|---|---|---|
| Specifies the Bluetooth device address in the form | An address is required for proxy endpoints. The plug-in will throw | On Linux, the plug-in uses the address to select the Bluetooth adapter on which to listen for new connections. If no address is specified via the On Android, the plug-in ignores this setting and always uses the system's default adapter. In addition to a Bluetooth device address, |
| Specifies the UUID of a service. | A UUID is required for proxy endpoints. The plug-in uses the UUID to search for a matching service at the specified device address. | A UUID is optional (but recommended) for object adapter endpoints. If this option is not specified, the plug-in generates a random UUID. The plug-in registers the service with its UUID in the local SDP registry so that clients can locate it. |
| Specifies the RFCOMM channel number of the endpoint. | Not supported in proxy endpoints – the plug-in always uses the service UUID to connect to a server. | This setting is optional on Linux. The value for This setting is ignored on Android – the system always selects the channel. |
| Specifies the endpoint timeout in milliseconds. | The value for Endpoint timeouts are deprecated. They have no effect as of Ice 3.8. | |
| Specifies bzip2 compression. | Determines whether requests are compressed during sending. | Determines whether compression is advertised in proxies created by the adapter. |
| Specifies the service name. | Ignored in proxy endpoints. | Associates a human-friendly name with the service's entry in the SDP registry. If not specified, the default name is |
iAP Endpoint Syntax
Synopsis
iap -p protocol -n name -m manufacturer -o model number -t timeout -ziaps -p protocol -n name -m manufacturer -o model number -t
Availability
The iAP transport protocol is provided by a separate IceIAP plug-in.
Description
The iAP transport protocol allows applications running on iOS to communicate with accessories connected to the iOS device either through Bluetooth or the lightning connector. The iAP transport protocol is a client-side transport protocol: there's no server-side support. An iAP endpoint supports the following options to allow selecting the accessory to connect to:
Option | Description | Client Semantics |
|---|---|---|
| Specifies the protocol implemented by the accessory. | The iAP transport protocol will only connect to accessories that advertise the specified iAP protocol. The default value for protocol is |
| Specifies the name of the accessory. | When specified, the iAP transport protocol will only connect to accessories that match the specified accessory name. |
| Specifies the manufacturer of the accessory. | When specified, the iAP transport protocol will only connect to accessories that match the specified accessory manufacturer. |
| Specifies the model number of the accessory. | When specified, the iAP transport protocol will only connect to accessories that match the specified accessory model number. |
| The value for Endpoint timeouts are deprecated. They have no effect as of Ice 3.8. | |
-z | Specifies bzip2 compression. | Determines whether requests are compressed during sending. |
Opaque Endpoint Syntax
Synopsis
opaque -t type -e encoding -v value
Description
Proxies can contain endpoints that are not universally understood by Ice processes. For example, a proxy can contain an endpoint for a transport that the receiver does not know.
Ice preserves such unknown endpoints when they are received over the wire. If an Ice process stringifies a proxy containing an unknown endpoint, it writes the endpoint as an opaque endpoint.
An opaque endpoint supports the following options:
Option | Description |
|---|---|
| Specifies the endpoint type (also known as transport code) for the endpoint. TCP is 1, SSL is 2, UDP is 3, etc. |
| Specifies the encoding version used to encode the endpoint marshaled data. |
| Specifies the marshaled encoding of the endpoint in base-64 encoding. |
Exactly one each of the -t and -v options must be present in an opaque endpoint. If -e is not specified, the default encoding used by the Ice runtime is assumed.