The RTCIceCandidate
interface's read-only address
property is a string providing the address of the device which is the source of the candidate. address
is null
by default if not otherwise specified.
The address
field's value is set when the RTCIceCandidate()
constructor is used. You can't specify the address
in the options object, but the address is automatically extracted from the candidate
a-line, if it's formatted properly.
Syntax
var address = RTCIceCandidate.address;
Value
A DOMString
providing the IP address from which the candidate comes.
Note: If port
is null
— and port
is supported by the user agent — passing the candidate to addIceCandidate()
will fail, throwing an OperationError
exception.
Security notes
It's important to note here that although WebRTC does not require the two peers on an RTCPeerConnection
to know one another's true IP addresses, the address
property on RTCIceCandidate
can expose more information about the source of the remote peer than the user expects. The IP address can be used to derive information about the remote device's location, network topology, and so forth. It can also be used for fingerprinting purposes.
The candidate IP addresses are always exposed to the application through address
, and unsavory applications can in turn potentially reveal the address to the user. This can occur without the remote peer's consent.
Applications being built with user privacy and security in mind can choose to limit the permitted candidates to relay candidates only. Doing so prevents the remote user's address from being exposed, but reduces the pool of available candidates to choose from. To do this, configure the ICE agent's ICE transport policy using RTCConfiguration
, like this:
var rtcConfig = { iceServers: [ { urls: "turn:myturn.server.ip", username: "username", credential: "password" } ], iceTransportPolicy: "relay" }
By setting RTCConfiguration.iceTransportPolicy
to "relay"
, any host candidates (candidates where the IP address is the peer's own IP address) are left out of the pool of candidates, as are any other candidates which aren't relay candidates.
Usage notes
Consider this SDP attribute line (a-line) which describes an ICE candidate:
a=candidate:4234997325 1 udp 2043278322 192.168.0.56 44323 typ host
The fifth field, "192.168.0.56"
is the IP address in this candidate's a-line string.
Example
This code snippet uses the value of address
to implement an IP address based ban feature.
if (ipBanList.includes(candidate.address)) { rejectCandidate(candidate); } else { acceptCandidate(candidate); }
Specifications
Specification | Status | Comment |
---|---|---|
WebRTC 1.0: Real-time Communication Between Browsers The definition of 'RTCIceCandidate: address' in that specification. |
Candidate Recommendation | Initial definition. |
Browser compatibility
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
address | Chrome Full support 74 | Edge
Full support
79
| Firefox ? | IE No support No | Opera ? | Safari ? | WebView Android Full support 74 | Chrome Android Full support 74 | Firefox Android ? | Opera Android ? | Safari iOS ? | Samsung Internet Android Full support 11.0 |
Legend
- Full support
- Full support
- No support
- No support
- Compatibility unknown
- Compatibility unknown
- Uses a non-standard name.
- Uses a non-standard name.