IfcDistributionPort是产品的入口或出口，特定物质可通过该入口或出口流动。
IfcDistributionPort用于固体、液体或气体物质的输送，也用于电力或通信。流段（管道、管道、电缆）可用于跨产品连接端口。分配端口由系统类型和流向定义，因此要连接两个端口，它们必须共享相同的系统类型并具有相反的流向（一边是源，另一边是汇）。端口类似于开口，因为它们没有任何可见的几何图形；此类几何图形在封闭元素或元素类型的形状表示中捕获。端口的位置可能指示连接的位置和方向。
在IFC2x2中增加的新实体
IFC4更改Ports属性现在与使用IfcRelNests关系的产品和产品类型相关；IfcRelConnectsPortToElement的使用现在保留给动态连接端口（例如在油箱中钻孔）。
| # | Attribute | Type | Cardinality | Description | C |
|---|---|---|---|---|---|
| IfcRoot | |||||
| 1 | GlobalId | IfcGloballyUniqueId | [1:1] | Assignment of a globally unique identifier within the entire software world. | X |
| 2 | OwnerHistory | IfcOwnerHistory | [0:1] | Assignment of the information about the current ownership of that object, including owning actor, application, local identification and information captured about the recent changes of the object,
NOTE only the last modification in stored - either as addition, deletion or modification. |
X |
| 3 | Name | IfcLabel | [0:1] | Optional name for use by the participating software systems or users. For some subtypes of IfcRoot the insertion of the Name attribute may be required. This would be enforced by a where rule. | X |
| 4 | Description | IfcText | [0:1] | Optional description, provided for exchanging informative comments. | X |
| IfcObjectDefinition | |||||
| HasAssignments | IfcRelAssigns @RelatedObjects |
S[0:?] | Reference to the relationship objects, that assign (by an association relationship) other subtypes of IfcObject to this object instance. Examples are the association to products, processes, controls, resources or groups. | X | |
| Nests | IfcRelNests @RelatedObjects |
S[0:1] | References to the decomposition relationship being a nesting. It determines that this object definition is a part within an ordered whole/part decomposition relationship. An object occurrence or type can only be part of a single decomposition (to allow hierarchical strutures only). | X | |
| IsNestedBy | IfcRelNests @RelatingObject |
S[0:?] | References to the decomposition relationship being a nesting. It determines that this object definition is the whole within an ordered whole/part decomposition relationship. An object or object type can be nested by several other objects (occurrences or types). | X | |
| HasContext | IfcRelDeclares @RelatedDefinitions |
S[0:1] | References to the context providing context information such as project unit or representation context. It should only be asserted for the uppermost non-spatial object. | X | |
| IsDecomposedBy | IfcRelAggregates @RelatingObject |
S[0:?] | References to the decomposition relationship being an aggregation. It determines that this object definition is whole within an unordered whole/part decomposition relationship. An object definitions can be aggregated by several other objects (occurrences or parts). | X | |
| Decomposes | IfcRelAggregates @RelatedObjects |
S[0:1] | References to the decomposition relationship being an aggregation. It determines that this object definition is a part within an unordered whole/part decomposition relationship. An object definitions can only be part of a single decomposition (to allow hierarchical strutures only). | X | |
| HasAssociations | IfcRelAssociates @RelatedObjects |
S[0:?] | Reference to the relationship objects, that associates external references or other resource definitions to the object.. Examples are the association to library, documentation or classification. | X | |
| IfcObject | |||||
| 5 | ObjectType | IfcLabel | [0:1] | The type denotes a particular type that indicates the object further. The use has to be established at the level of instantiable subtypes. In particular it holds the user defined type, if the enumeration of the attribute PredefinedType is set to USERDEFINED. | X |
| IsDeclaredBy | IfcRelDefinesByObject @RelatedObjects |
S[0:1] | Link to the relationship object pointing to the declaring object that provides the object definitions for this object occurrence. The declaring object has to be part of an object type decomposition. The associated IfcObject, or its subtypes, contains the specific information (as part of a type, or style, definition), that is common to all reflected instances of the declaring IfcObject, or its subtypes. | X | |
| Declares | IfcRelDefinesByObject @RelatingObject |
S[0:?] | Link to the relationship object pointing to the reflected object(s) that receives the object definitions. The reflected object has to be part of an object occurrence decomposition. The associated IfcObject, or its subtypes, provides the specific information (as part of a type, or style, definition), that is common to all reflected instances of the declaring IfcObject, or its subtypes. | X | |
| IsTypedBy | IfcRelDefinesByType @RelatedObjects |
S[0:1] | Set of relationships to the object type that provides the type definitions for this object occurrence. The then associated IfcTypeObject, or its subtypes, contains the specific information (or type, or style), that is common to all instances of IfcObject, or its subtypes, referring to the same type. | X | |
| IsDefinedBy | IfcRelDefinesByProperties @RelatedObjects |
S[0:?] | Set of relationships to property set definitions attached to this object. Those statically or dynamically defined properties contain alphanumeric information content that further defines the object. | X | |
| IfcProduct | |||||
| 6 | ObjectPlacement | IfcObjectPlacement | [0:1] | Placement of the product in space, the placement can either be absolute (relative to the world coordinate system), relative (relative to the object placement of another product), or constraint (e.g. relative to grid axes). It is determined by the various subtypes of IfcObjectPlacement, which includes the axis placement information to determine the transformation for the object coordinate system. | X |
| 7 | Representation | IfcProductRepresentation | [0:1] | Reference to the representations of the product, being either a representation (IfcProductRepresentation) or as a special case a shape representations (IfcProductDefinitionShape). The product definition shape provides for multiple geometric representations of the shape property of the object within the same object coordinate system, defined by the object placement. | X |
| ReferencedBy | IfcRelAssignsToProduct @RelatingProduct |
S[0:?] | Reference to the IfcRelAssignsToProduct relationship, by which other products, processes, controls, resources or actors (as subtypes of IfcObjectDefinition) can be related to this product. | X | |
| IfcPort | |||||
| ContainedIn | IfcRelConnectsPortToElement @RelatingPort |
S[0:1] | Reference to the element to port connection relationship. The relationship then refers to the element in which this port is contained. | X | |
| ConnectedFrom | IfcRelConnectsPorts @RelatedPort |
S[0:1] | Reference to a port that is connected by the objectified relationship. | X | |
| ConnectedTo | IfcRelConnectsPorts @RelatingPort |
S[0:1] | Reference to the port connection relationship. The relationship then refers to the other port to which this port is connected. | X | |
| IfcDistributionPort | |||||
| 8 | FlowDirection | IfcFlowDirectionEnum | [0:1] | Enumeration that identifies if this port is a Sink (inlet), a Source (outlet) or both a SinkAndSource. | X |
| 9 | PredefinedType | IfcDistributionPortTypeEnum | [0:1] | X | |
| 10 | SystemType | IfcDistributionSystemEnum | [0:1] | Enumeration that identifies the system type. If a system type is defined, the port may only be connected to other ports having the same system type. | X |