diff --git a/sylk/applications/webrtcgateway/models/sylkrtc.py b/sylk/applications/webrtcgateway/models/sylkrtc.py
index c3ad117..9a31331 100644
--- a/sylk/applications/webrtcgateway/models/sylkrtc.py
+++ b/sylk/applications/webrtcgateway/models/sylkrtc.py
@@ -1,633 +1,636 @@
 
 from application.python import subclasses
 
 from .jsonobjects import BooleanProperty, IntegerProperty, StringProperty, ArrayProperty, ObjectProperty, FixedValueProperty, LimitedChoiceProperty, AbstractObjectProperty, AbstractProperty
 from .jsonobjects import JSONObject, JSONArray, StringArray, CompositeValidator
 from .validators import AORValidator, DisplayNameValidator, LengthValidator, UniqueItemsValidator
 
 from sipsimple.util import ISOTimestamp
 
 # Base models (these are abstract and should not be used directly)
 
 class SylkRTCRequestBase(JSONObject):
     transaction = StringProperty()
 
 
 class SylkRTCResponseBase(JSONObject):
     transaction = StringProperty()
 
 
 class AccountRequestBase(SylkRTCRequestBase):
     account = StringProperty(validator=AORValidator())
 
 
 class SessionRequestBase(SylkRTCRequestBase):
     session = StringProperty()
 
 
 class VideoroomRequestBase(SylkRTCRequestBase):
     session = StringProperty()
 
 
 class AccountEventBase(JSONObject):
     sylkrtc = FixedValueProperty('account-event')
     account = StringProperty(validator=AORValidator())
 
 
 class SessionEventBase(JSONObject):
     sylkrtc = FixedValueProperty('session-event')
     session = StringProperty()
 
 
 class VideoroomEventBase(JSONObject):
     sylkrtc = FixedValueProperty('videoroom-event')
     session = StringProperty()
 
 
 class AccountRegistrationStateEvent(AccountEventBase):
     event = FixedValueProperty('registration-state')
 
 
 class SessionStateEvent(SessionEventBase):
     event = FixedValueProperty('state')
 
 
 class VideoroomSessionStateEvent(VideoroomEventBase):
     event = FixedValueProperty('session-state')
 
 
 # Miscellaneous models
 
 class Header(JSONObject):
     name = StringProperty()
     value = StringProperty()
 
 
 class Headers(JSONArray):
     item_type = Header
 
 
 class SIPIdentity(JSONObject):
     uri = StringProperty(validator=AORValidator())
     display_name = StringProperty(optional=True, validator=DisplayNameValidator())
 
 
 class ICECandidate(JSONObject):
     candidate = StringProperty()
     sdpMLineIndex = IntegerProperty()
     sdpMid = StringProperty()
 
 
 class ICECandidates(JSONArray):
     item_type = ICECandidate
 
 
 class AORList(StringArray):
     list_validator = UniqueItemsValidator()
     item_validator = AORValidator()
 
 
 class VideoroomPublisher(JSONObject):
     id = StringProperty()
     uri = StringProperty(validator=AORValidator())
     display_name = StringProperty(optional=True)
 
 
 class VideoroomPublishers(JSONArray):
     item_type = VideoroomPublisher
 
 
 class VideoroomActiveParticipants(StringArray):
     list_validator = CompositeValidator(UniqueItemsValidator(), LengthValidator(maximum=2))
 
 
 class VideoroomSessionOptions(JSONObject):
     audio = BooleanProperty(optional=True)
     video = BooleanProperty(optional=True)
     bitrate = IntegerProperty(optional=True)
 
 
 class VideoroomRaisedHands(StringArray):
     list_validator = UniqueItemsValidator()
 
 
 class SharedFile(JSONObject):
     filename = StringProperty()
     filesize = IntegerProperty()
     uploader = ObjectProperty(SIPIdentity)  # type: SIPIdentity
     session = StringProperty()
 
 
 class SharedFiles(JSONArray):
     item_type = SharedFile
 
 
 class TransferredFile(JSONObject):
     filename = StringProperty()
     filesize = IntegerProperty()
     sender = ObjectProperty(SIPIdentity)  # type: SIPIdentity
     receiver = ObjectProperty(SIPIdentity)
     transfer_id = StringProperty()
     prefix = StringProperty()
     path = StringProperty()
     timestamp = StringProperty()
+    url = StringProperty(optional=True)
+    filetype = StringProperty(optional=True)
+    hash = StringProperty(optional=True)
 
 
 class DispositionNotifications(StringArray):
     list_validator = UniqueItemsValidator()
 
 
 class Message(JSONObject):
     contact = StringProperty(validator=AORValidator())
     timestamp = StringProperty()
     disposition = ArrayProperty(DispositionNotifications, optional=True)
     message_id = StringProperty()
     content_type = StringProperty()
     content = StringProperty()
     direction = StringProperty(optional=True)
     state = LimitedChoiceProperty(['delivered', 'failed', 'displayed', 'forbidden', 'error', 'accepted', 'pending', 'received'], optional=True)
 
     def __init__(self, **kw):
         if 'msg_timestamp' in kw:
             kw['timestamp'] = str(ISOTimestamp(kw['msg_timestamp']))
             del kw['msg_timestamp']
         super(Message, self).__init__(**kw)
 
 
 class ContactMessages(JSONArray):
     item_type = Message
 
 
 class MessageHistoryData(JSONObject):
     account = StringProperty(validator=AORValidator())
     messages = ArrayProperty(ContactMessages)
 
 
 class AccountMessageRemoveEventData(JSONObject):
     contact = StringProperty()
     message_id = StringProperty()
 
 
 class AccountMarkConversationReadEventData(JSONObject):
     contact = StringProperty()
 
 
 class AccountConversationRemoveEventData(JSONObject):
     contact = StringProperty()
 
 
 class AccountDispositionNotificationEventData(JSONObject):
     message_id = StringProperty()
     state = LimitedChoiceProperty(['accepted', 'delivered', 'displayed', 'failed', 'processed', 'stored', 'forbidden', 'error'])
     message_timstamp = StringProperty()
     code = IntegerProperty()
     reason = StringProperty()
 
 
 class IncomingHeaderPrefixes(StringArray):
     list_validator = UniqueItemsValidator()
 
 
 # Response models
 
 class AckResponse(SylkRTCResponseBase):
     sylkrtc = FixedValueProperty('ack')
 
 
 class ErrorResponse(SylkRTCResponseBase):
     sylkrtc = FixedValueProperty('error')
     error = StringProperty()
 
 
 # Connection events
 
 class ReadyEvent(JSONObject):
     sylkrtc = FixedValueProperty('ready-event')
 
 
 class LookupPublicKeyEvent(JSONObject):
     sylkrtc = FixedValueProperty('lookup-public-key-event')
     uri = StringProperty(validator=AORValidator())
     public_key = StringProperty(optional=True)
 
 
 # Account events
 
 class AccountIncomingSessionEvent(AccountEventBase):
     event = FixedValueProperty('incoming-session')
     session = StringProperty()
     originator = ObjectProperty(SIPIdentity)  # type: SIPIdentity
     sdp = StringProperty()
     call_id = StringProperty()
     headers = AbstractProperty(optional=True)
 
 
 class AccountMissedSessionEvent(AccountEventBase):
     event = FixedValueProperty('missed-session')
     originator = ObjectProperty(SIPIdentity)  # type: SIPIdentity
 
 
 class AccountConferenceInviteEvent(AccountEventBase):
     event = FixedValueProperty('conference-invite')
     room = StringProperty(validator=AORValidator())
     session_id = StringProperty()
     originator = ObjectProperty(SIPIdentity)  # type: SIPIdentity
 
 
 class AccountMessageEvent(AccountEventBase):
     event = FixedValueProperty('message')
     sender = ObjectProperty(SIPIdentity)  # type: SIPIdentity
     timestamp = StringProperty()
     disposition_notification = ArrayProperty(DispositionNotifications, optional=True)
     message_id = StringProperty()
     content_type = StringProperty()
     content = StringProperty()
     direction = StringProperty(optional=True)
 
 
 class AccountDispositionNotificationEvent(AccountEventBase):
     event = FixedValueProperty('disposition-notification')
     message_id = StringProperty()
     message_timestamp = StringProperty()
     state = LimitedChoiceProperty(['accepted', 'delivered', 'displayed', 'failed', 'processed', 'stored', 'forbidden', 'error'])
     code = IntegerProperty()
     reason = StringProperty()
 
 
 class AccountSyncConversationsEvent(AccountEventBase):
     event = FixedValueProperty('sync-conversations')
     messages = ArrayProperty(ContactMessages)
 
 
 class AccountSyncEvent(AccountEventBase):
     event = FixedValueProperty('sync')
     type = StringProperty()
     action = StringProperty()
     content = AbstractObjectProperty()
 
 
 class AccountRegisteringEvent(AccountRegistrationStateEvent):
     state = FixedValueProperty('registering')
 
 
 class AccountRegisteredEvent(AccountRegistrationStateEvent):
     state = FixedValueProperty('registered')
 
 
 class AccountRegistrationFailedEvent(AccountRegistrationStateEvent):
     state = FixedValueProperty('failed')
     reason = StringProperty(optional=True)
 
 
 # Session events
 
 class SessionProgressEvent(SessionStateEvent):
     state = FixedValueProperty('progress')
 
 
 class SessionEarlyMediaEvent(SessionStateEvent):
     state = FixedValueProperty('early-media')
     sdp = StringProperty(optional=True)
     call_id = StringProperty(optional=True)
 
 
 class SessionAcceptedEvent(SessionStateEvent):
     state = FixedValueProperty('accepted')
     sdp = StringProperty(optional=True)  # missing for incoming sessions
     call_id = StringProperty(optional=True)
     headers = AbstractProperty(optional=True)
 
 
 class SessionEstablishedEvent(SessionStateEvent):
     state = FixedValueProperty('established')
 
 
 class SessionTerminatedEvent(SessionStateEvent):
     state = FixedValueProperty('terminated')
     reason = StringProperty(optional=True)
 
 
 class SessionMessageEvent(SessionEventBase):
     event = FixedValueProperty('message')
     sender = ObjectProperty(SIPIdentity)  # type: SIPIdentity
     timestamp = StringProperty()
     disposition_notification = ArrayProperty(DispositionNotifications, optional=True)
     message_id = StringProperty()
     content_type = StringProperty()
     content = StringProperty()
     direction = StringProperty(optional=True)
 
 
 class SessionMessageDispositionNotificationEvent(SessionEventBase):
     event = FixedValueProperty('disposition-notification')
     message_id = StringProperty()
     message_timestamp = StringProperty()
     state = LimitedChoiceProperty(['accepted', 'delivered', 'displayed', 'failed', 'processed', 'stored', 'forbidden', 'error'])
     code = IntegerProperty()
     reason = StringProperty()
 
 
 # Video room events
 
 class VideoroomConfigureEvent(VideoroomEventBase):
     event = FixedValueProperty('configure')
     originator = StringProperty()
     active_participants = ArrayProperty(VideoroomActiveParticipants)  # type: VideoroomActiveParticipants
 
 
 class VideoroomSessionProgressEvent(VideoroomSessionStateEvent):
     state = FixedValueProperty('progress')
 
 
 class VideoroomSessionAcceptedEvent(VideoroomSessionStateEvent):
     state = FixedValueProperty('accepted')
     sdp = StringProperty()
     video = BooleanProperty(optional=True, default=True)
     audio = BooleanProperty(optional=True, default=True)
 
 
 class VideoroomSessionEstablishedEvent(VideoroomSessionStateEvent):
     state = FixedValueProperty('established')
 
 
 class VideoroomSessionTerminatedEvent(VideoroomSessionStateEvent):
     state = FixedValueProperty('terminated')
     reason = StringProperty(optional=True)
 
 
 class VideoroomFeedAttachedEvent(VideoroomEventBase):
     event = FixedValueProperty('feed-attached')
     feed = StringProperty()
     sdp = StringProperty()
 
 
 class VideoroomFeedEstablishedEvent(VideoroomEventBase):
     event = FixedValueProperty('feed-established')
     feed = StringProperty()
 
 
 class VideoroomInitialPublishersEvent(VideoroomEventBase):
     event = FixedValueProperty('initial-publishers')
     publishers = ArrayProperty(VideoroomPublishers)  # type: VideoroomPublishers
 
 
 class VideoroomPublishersJoinedEvent(VideoroomEventBase):
     event = FixedValueProperty('publishers-joined')
     publishers = ArrayProperty(VideoroomPublishers)  # type: VideoroomPublishers
 
 
 class VideoroomPublishersLeftEvent(VideoroomEventBase):
     event = FixedValueProperty('publishers-left')
     publishers = ArrayProperty(StringArray)          # type: StringArray
 
 
 class VideoroomFileSharingEvent(VideoroomEventBase):
     event = FixedValueProperty('file-sharing')
     files = ArrayProperty(SharedFiles)               # type: SharedFiles
 
 
 class VideoroomMessageEvent(VideoroomEventBase):
     event = FixedValueProperty('message')
     type = LimitedChoiceProperty(['normal', 'status'])
     content = StringProperty()
     content_type = StringProperty()
     sender = ObjectProperty(SIPIdentity)  # type: SIPIdentity
     timestamp = StringProperty()
 
 
 class VideoroomComposingIndicationEvent(VideoroomEventBase):
     event = FixedValueProperty('composing-indication')
     state = StringProperty()
     refresh = IntegerProperty()
     content_type = StringProperty()
     sender = ObjectProperty(SIPIdentity)  # type: SIPIdentity
 
 
 class VideoroomMessageDeliveryEvent(VideoroomEventBase):
     event = FixedValueProperty('message-delivery')
     message_id = StringProperty()
     delivered = BooleanProperty()
     code = IntegerProperty()
     reason = StringProperty()
 
 
 class VideoroomMuteAudioEvent(VideoroomEventBase):
     event = FixedValueProperty('mute-audio')
     originator = StringProperty()
 
 
 class VideoroomRaisedHandsEvent(VideoroomEventBase):
     event = FixedValueProperty('raised-hands')
     raised_hands = ArrayProperty(VideoroomRaisedHands)
 
 
 # Ping request model, can be used to check connectivity from client
 
 class PingRequest(SylkRTCRequestBase):
     sylkrtc = FixedValueProperty('ping')
 
 
 # Lookup Public key model
 
 class LookupPublicKeyRequest(SylkRTCRequestBase):
     sylkrtc = FixedValueProperty('lookup-public-key')
     uri = StringProperty(validator=AORValidator())
 
 
 # Account request models
 
 class AccountAddRequest(AccountRequestBase):
     sylkrtc = FixedValueProperty('account-add')
     password = StringProperty(validator=LengthValidator(minimum=1, maximum=9999))
     display_name = StringProperty(optional=True)
     user_agent = StringProperty(optional=True)
     incoming_header_prefixes = ArrayProperty(IncomingHeaderPrefixes, optional=True)
 
 
 class AccountRemoveRequest(AccountRequestBase):
     sylkrtc = FixedValueProperty('account-remove')
 
 
 class AccountRegisterRequest(AccountRequestBase):
     sylkrtc = FixedValueProperty('account-register')
 
 
 class AccountUnregisterRequest(AccountRequestBase):
     sylkrtc = FixedValueProperty('account-unregister')
 
 
 class AccountDeviceTokenRequest(AccountRequestBase):
     sylkrtc = FixedValueProperty('account-devicetoken')
     token = StringProperty()
     platform = StringProperty()
     device = StringProperty()
     silent = BooleanProperty(default=False)
     app = StringProperty()
 
 
 class AccountMessageRequest(AccountRequestBase):
     sylkrtc = FixedValueProperty('account-message')
     uri = StringProperty(validator=AORValidator())
     message_id = StringProperty()
     content = StringProperty()
     content_type = StringProperty()
     timestamp = StringProperty()
     server_generated = BooleanProperty(optional=True)
 
 
 class AccountDispositionNotificationRequest(AccountRequestBase):
     sylkrtc = FixedValueProperty('account-disposition-notification')
     uri = StringProperty(validator=AORValidator())
     message_id = StringProperty()
     state = LimitedChoiceProperty(['delivered', 'failed', 'displayed', 'forbidden', 'error'])
     timestamp = StringProperty()
 
 
 class AccountSyncConversationsRequest(AccountRequestBase):
     sylkrtc = FixedValueProperty('account-sync-conversations')
     message_id = StringProperty(optional=True)
 
 
 class AccountMarkConversationReadRequest(AccountRequestBase):
     sylkrtc = FixedValueProperty('account-mark-conversation-read')
     contact = StringProperty(validator=AORValidator())
 
 
 class AccountMessageRemoveRequest(AccountRequestBase):
     sylkrtc = FixedValueProperty('account-remove-message')
     message_id = StringProperty()
     contact = StringProperty(validator=AORValidator())
 
 
 class AccountConversationRemoveRequest(AccountRequestBase):
     sylkrtc = FixedValueProperty('account-remove-conversation')
     contact = StringProperty(validator=AORValidator())
 
 
 # Session request models
 
 class SessionCreateRequest(SessionRequestBase):
     sylkrtc = FixedValueProperty('session-create')
     account = StringProperty(validator=AORValidator())
     uri = StringProperty(validator=AORValidator())
     sdp = StringProperty()
     headers = ArrayProperty(Headers, optional=True)
 
 
 class SessionAnswerRequest(SessionRequestBase):
     sylkrtc = FixedValueProperty('session-answer')
     sdp = StringProperty()
     headers = ArrayProperty(Headers, optional=True)
 
 
 class SessionTrickleRequest(SessionRequestBase):
     sylkrtc = FixedValueProperty('session-trickle')
     candidates = ArrayProperty(ICECandidates)  # type: ICECandidates
 
 
 class SessionTerminateRequest(SessionRequestBase):
     sylkrtc = FixedValueProperty('session-terminate')
 
 
 class SessionMessageRequest(SessionRequestBase):
     sylkrtc = FixedValueProperty('session-message')
     message_id = StringProperty()
     content = StringProperty()
     content_type = StringProperty()
     timestamp = StringProperty()
 
 
 # Videoroom request models
 
 class VideoroomJoinRequest(VideoroomRequestBase):
     sylkrtc = FixedValueProperty('videoroom-join')
     account = StringProperty(validator=AORValidator())
     uri = StringProperty(validator=AORValidator())
     sdp = StringProperty()
     audio = BooleanProperty(optional=True, default=True)
     video = BooleanProperty(optional=True, default=True)
 
 
 class VideoroomLeaveRequest(VideoroomRequestBase):
     sylkrtc = FixedValueProperty('videoroom-leave')
 
 
 class VideoroomConfigureRequest(VideoroomRequestBase):
     sylkrtc = FixedValueProperty('videoroom-configure')
     active_participants = ArrayProperty(VideoroomActiveParticipants)  # type: VideoroomActiveParticipants
 
 
 class VideoroomFeedAttachRequest(VideoroomRequestBase):
     sylkrtc = FixedValueProperty('videoroom-feed-attach')
     publisher = StringProperty()
     feed = StringProperty()
 
 
 class VideoroomFeedAnswerRequest(VideoroomRequestBase):
     sylkrtc = FixedValueProperty('videoroom-feed-answer')
     feed = StringProperty()
     sdp = StringProperty()
 
 
 class VideoroomFeedDetachRequest(VideoroomRequestBase):
     sylkrtc = FixedValueProperty('videoroom-feed-detach')
     feed = StringProperty()
 
 
 class VideoroomInviteRequest(VideoroomRequestBase):
     sylkrtc = FixedValueProperty('videoroom-invite')
     participants = ArrayProperty(AORList)              # type: AORList
 
 
 class VideoroomSessionTrickleRequest(VideoroomRequestBase):
     sylkrtc = FixedValueProperty('videoroom-session-trickle')
     candidates = ArrayProperty(ICECandidates)          # type: ICECandidates
 
 
 class VideoroomSessionUpdateRequest(VideoroomRequestBase):
     sylkrtc = FixedValueProperty('videoroom-session-update')
     options = ObjectProperty(VideoroomSessionOptions)  # type: VideoroomSessionOptions
 
 
 class VideoroomMessageRequest(VideoroomRequestBase):
     sylkrtc = FixedValueProperty('videoroom-message')
     message_id = StringProperty()
     content = StringProperty()
     content_type = StringProperty()
 
 
 class VideoroomComposingIndicationRequest(VideoroomRequestBase):
     sylkrtc = FixedValueProperty('videoroom-composing-indication')
     state = LimitedChoiceProperty(['active', 'idle'])
     refresh = IntegerProperty(optional=True)
 
 
 class VideoroomMuteAudioParticipantsRequest(VideoroomRequestBase):
     sylkrtc = FixedValueProperty('videoroom-mute-audio-participants')
 
 
 class VideoroomToggleHandRequest(VideoroomRequestBase):
     sylkrtc = FixedValueProperty('videoroom-toggle-hand')
     session_id = StringProperty(optional=True)
 
 
 # SylkRTC request to model mapping
 
 class ProtocolError(Exception):
     pass
 
 
 class SylkRTCRequest(object):
     __classmap__ = {cls.sylkrtc.value: cls for cls in subclasses(SylkRTCRequestBase) if hasattr(cls, 'sylkrtc')}
 
     @classmethod
     def from_message(cls, message):
         try:
             request_type = message['sylkrtc']
         except KeyError:
             raise ProtocolError('could not get WebSocket message type')
         try:
             request_class = cls.__classmap__[request_type]
         except KeyError:
             raise ProtocolError('unknown WebSocket request: %s' % request_type)
         return request_class(**message)