Opc.Ua.Com.Server.ComDaGroupManager.AddGroup C# (CSharp) Method

        public ComDaGroup AddGroup(
            string groupName,
            bool active,
            int updateRate,
            int clientHandle,
            int timeBias,
            float deadband,
            int lcid)
        {
            TraceState("AddGroup", groupName, active, updateRate, clientHandle, timeBias, deadband, lcid);

            // check for valid session.
            Session session = m_session;

            if (session == null)
            {
                throw ComUtils.CreateComException(ResultIds.E_FAIL);
            }

            ComDaGroup group = null;

            // check for duplicate name.
            lock (m_lock)
            {
                // ensure the name is unique.
                if (!String.IsNullOrEmpty(groupName))
                {
                    if (GetGroupByName(groupName) != null)
                    {
                        throw ComUtils.CreateComException(ResultIds.E_DUPLICATENAME);
                    }
                }

                // assign a unique name.
                else
                {
                    groupName = Utils.Format("Group{0}", m_groupCounter+1);
                }

                // validate the deadband.
                if (deadband < 0 || deadband > 100)
                {
                    throw ComUtils.CreateComException(ResultIds.E_INVALIDARG);
                }

                // create the group.
                group = new ComDaGroup(this, groupName, ++m_groupCounter);
                m_groups.Add(group);

                group.ClientHandle = clientHandle;
                group.Active = active;
                group.UpdateRate = updateRate;
                group.TimeBias = timeBias;
                group.Deadband = deadband;
                group.Lcid = lcid;

                if (updateRate < 100)
                {
                    updateRate = 100;
                }

                // create a new subscription.
                Subscription subscription = new Subscription();
                subscription.DisplayName = groupName;
                subscription.PublishingInterval = updateRate/2;
                subscription.KeepAliveCount = 30;
                subscription.LifetimeCount = 600;
                subscription.MaxNotificationsPerPublish = 10000;
                subscription.Priority = 1;
                subscription.PublishingEnabled = active;
                subscription.DisableMonitoredItemCache = true;
                
                // create the subscription on the server.
                session.AddSubscription(subscription);

                try
                {
                    // create the initial subscription.
                    subscription.Create();

                    // set the keep alive interval to 30 seconds and the the lifetime interval to 5 minutes.
                    subscription.KeepAliveCount = (uint)((30000/(int)subscription.CurrentPublishingInterval)+1);
                    subscription.LifetimeCount = (uint)((600000/(int)subscription.CurrentPublishingInterval)+1);

                    // update the subscription.
                    subscription.Modify();
                }
                catch (Exception e)
                {
                    session.RemoveSubscription(subscription);
                    Utils.Trace((int)Utils.TraceMasks.Error, "Create subscription failed: {0}", e.Message);
                    throw ComUtils.CreateComException(e, ResultIds.E_FAIL);
                }

                // update the group.
                group.ActualUpdateRate = (int)(subscription.CurrentPublishingInterval*2);
                group.Subscription = subscription;
            }

            return group;
        }