Warmth policy

[robin-raymond]

We don't current have one but something is needed at minimal.

Scenario: Offer containing candidates is given but before any (or all) answers arrive, the candidates become stale due to inactivity.

Scenario: Always want to keep a TCP relay connection open as a backup should local addresses become disconnected (e.g. backup wwan connection is alive but local wifi lan goes down).

I'm sure a ton of other scenarios can be dreamed up but we need something at minimal as a proposal. As such, here's my spaghetti on wall idea to promote discussion:

(again, not sure how to express in WebIDL, but if it were C++)

enum WarmthPolicy {
  KeepWarmUntilIceCompleted = 0x00000001,

  AlwaysKeepServerReflexiveWarm = 0x00000010,
  AlwaysKeepRelayUdpWarm = 0x00000020,
  AlwaysKeepRelayTcpWarm = 0x00000040, 

  AlwaysKeepWLanWarm = 0x00001000,
  AlwaysKeepWWanWarm = 0x00002000,
  AlwaysKeepVpnWarm = 0x00004000
};

We can add a simple: setWarmthPolicy(...) onto the API.

[robin-raymond]

http://lists.w3.org/Archives/Public/public-ortc/2014Apr/0032.html

[martinthomson]

EnumSets can be represented as arrays or sequences (JavaScript has no sets), with string values.

[juberti]

Since typically you won't want to keep wwan hot at the same time as wlan (due to battery concerns), I don't think we have a clear use case here.

This will almost certainly require ICE work in IETF too, so I don't think this will be that simple.

[robin-raymond]

Use case: Plugged in stationary mobile tablet with wwan enabled (i.e. no battery concerns). You keep wwan hot in case person detaches and starts walking outside the wlan specific area while in a call (at least for a specific period of time).

[juberti]

I hear what you are saying, but that use case seems very specific. The general solution that I think you would want would be to proactively bring up wwan when the signal strength for wlan drops below some threshold. But that is something different altogether.

[aboba]

Peter: Backup candidate pairs make sense, but not sure if this level of control is necessary.