Packages and high-priority mail are handled by The Typical Large Corporation (TyplCorp) in a way that is typical of large corporations. Each company building has a centralized mailroom where packages are received from personnel from various departments. Packages destined for other offices in the same building are delivered directly by the mailroom to those offices. Other packages are picked up by a van driver for OPS (Other Parcel Service) for handling and delivery by OPS. The OPS driver delivers the packages to a local district OPS office where packages are sorted for shipment to different areas. Packages with addresses within the district are delivered directly by the local OPS drivers. Other packages are trucked to the nearest OPS central air shipping facility. At OPS air shipping facilities, packages are normally each shipped to a facility near their destination, trucked to a district office, and delivered. However, during peak seasons or bad flying weather, some packages may be shipped more indirectly, by truck or air, through multiple central facilities and district offices, before they reach their final destination. Network professionals would argue that the OPS model is nearly identical to the TCP/IP model conceptually. Carefully describe the similarities between these two models.