The TS_VIRTUALCHANNEL_CAPABILITYSET structure is used to advertise virtual channel support characteristics. This capability is sent by both client and server.
file:///C:/ts_dev/TestSuites/MS-RDPBCGR/TestSuite/Src/TD/latest_XMLS_16may/RDPBCGR/ _rfc_ms-rdpbcgr2_1_6_1_11.xml
        /// <summary>
        /// Create a TS_VIRTUALCHANNEL_CAPABILITYSET type Capability, 2.2.7.1.10
        /// </summary>
        /// <param name="supportCompression"></param>
        /// <param name="presentChunkSize"></param>
        public static TS_VIRTUALCHANNEL_CAPABILITYSET CreateVirtualChannelCapSet(bool supportCompression, bool presentChunkSize)
        {
            TS_VIRTUALCHANNEL_CAPABILITYSET virtualChannelSet = new TS_VIRTUALCHANNEL_CAPABILITYSET();
            virtualChannelSet.capabilitySetType = capabilitySetType_Values.CAPSTYPE_VIRTUALCHANNEL;

            if (supportCompression)
            {
                virtualChannelSet.flags = TS_VIRTUALCHANNEL_CAPABILITYSET_flags_Values.VCCAPS_COMPR_CS_8K;
            }
            else
            {
                virtualChannelSet.flags = TS_VIRTUALCHANNEL_CAPABILITYSET_flags_Values.VCCAPS_NO_COMPR;
            }

            if (presentChunkSize)
            {
                virtualChannelSet.VCChunkSize = 1600;//CHANNEL_CHUNK_LENGTH
                virtualChannelSet.lengthCapability = 12;
            }
            else
            {
                virtualChannelSet.lengthCapability = 8;//it should be 8, SDK bug, VCChunkSize is optional.
                virtualChannelSet.VCChunkSize = 0;
            }
            return virtualChannelSet;
        }
 /// <summary>
 /// 2.2.7.1.10
 /// Check the requirements in structure TS_VIRTUALCHANNEL_CAPABILITYSET.
 /// </summary>
 /// <param name="vc">The TS_VIRTUALCHANNEL_CAPABILITYSET structure</param>
 public void VerifyStructure(TS_VIRTUALCHANNEL_CAPABILITYSET vc)
 {
     site.CaptureRequirementIfAreEqual<capabilitySetType_Values>(capabilitySetType_Values.CAPSTYPE_VIRTUALCHANNEL, vc.capabilitySetType, 1378,
         @"In TS_VIRTUALCHANNEL_CAPABILITYSET structure, capabilitySetType field MUST be set to "
         + @"CAPSTYPE_VIRTUALCHANNEL (20).");
 }