[MS-ASCMD]: ActiveSync Command Reference Protocol Specification

2.2.3.156.2 SyncKey (FolderSync)
The SyncKey element is a required child element of the FolderSync element in FolderSync
command requests and an optional child element of the FolderSync element in FolderSync
command responses. In both contexts, it is used by the server to track the current state of the
client.
All elements referenced in this section are defined in the FolderHierarchy namespace.
Command
request/response
Parent elements
Child
elements
Data type
Number
allowed
FolderSync command
request (section 2.2.2.4.1)
FolderSync
(section 2.2.3.67)
None
string ([MS-
ASDTYPE] section
2.6)
1…1
(required)
FolderSync command
response (section 2.2.2.4.2)
FolderSync None string 0…1
(optional)
After successful folder synchronization, the server MUST send a synchronization key to the client.
The client MUST store this key and send the key back to the server the next time the folder
hierarchy is synchronized or updated. The server MUST check the value of the key to make sure the
value of the SyncKey element provided in the request matches a synchronization key value on the
server. The server MUST return a Status element (section 2.2.3.152.4) value of 9 if the value of the
SyncKey element does not match the value of the synchronization key on the server.
The client MUST store the synchronization key as an opaque string of up to 64 characters.
If a synchronization error occurs, and the FolderSync response contains a Status element value of
9 (see section 2.2.3.152.4) then the client MUST restart the synchronization process with a
synchronization key of 0. The client's folder hierarchy list MUST be rebuilt and any changes that
existed on the client that had not been propagated to the server prior to the error SHOULD be sent
after the FolderSync operation is complete.
2.2.3.156.3 SyncKey (GetItemEstimate)
The airsync:SyncKey element is a required child element of the Collection element in
GetItemEstimate command requests that represents the current state of a collection.
Elements referenced in this section are defined in the GetItemEstimate namespace, except where
otherwise indicated by the presence of a namespace prefix (as defined in section 2.2.1).
Command request/response
Parent elements
Child
elements
Data type
Number
allowed
GetItemEstimate command
request (section 2.2.2.7.1)
Collection
(section
2.2.3.28.1)
None
string ([MS-
ASDTYPE] section
2.6)
1…1
(required)
The value of the element is examined by the server to determine the state of the synchronization
process. The airsync:SyncKey element is the first child element of the Collection element (section
2.2.3.28.1) in a GetItemEstimate command request.
The airsync:SyncKey element value used within the GetItemEstimate requests is the same as
the one returned within the Sync responses. The server does not update the airsync:SyncKey
value on GetItemEstimate requests. For more details about the airsync:SyncKey element, see
[MS-ASCMD] — v20110315
ActiveSync Command Reference Protocol Specification
Copyright © 2011 Microsoft Corporation.
Release: Tuesday, March 15, 2011
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