Roughly speaking, tunneling protocols operate at the transport layer, such as carrying non-IP protocols such as IBM's SNA or Novell's IPX over an IP network, or end-to-end encryption with IPsec.
model | Model (person) | America's Next Top Model | Ford Model T | New Model Army | model (person) | Model United Nations | IPTC Information Interchange Model | Lockheed Model 10 Electra | Standard Model | Model (profession) | Elite Model Management | RGB color model | Model Engineering College | Fetish model | business model | Beechcraft Model 18 | Scale model | Nice model | New Model Army (band) | Model Railroader | model (profession) | Lisette Model | Document Object Model | Component Object Model | Asia's Next Top Model | America's Most Smartest Model | Walter Model | Trump Model Management | scale model |
Use of SDLC at the data link layer permits 250 nodes on one segment with a total distance of 13.2 km.
It uses a layered device driver architecture, using a simple binding model, to allow operating system agnostic or independent portability; meaning that the file system is compatible with most operating systems and is thus not bound to any one RTOS.
External Data Representation, an implementation of the OSI model presentation layer