The Internetworking Problem
Scaling:
- How to support a large number of end-nodes and applications in this interconnected network ?
Possible solutions:
- Translation (eg: bridges): specify a separate mapping between every pair of protocols
- (+) No software changes in networks required.
- (-) Need to specify N mappings when a new lower layer protocol is added to the list
- (-) When many networks, subset = 0
- (-) Mapping may be asymmetric
- Overlay model: Define a new protocol (IP) and map all networks to IP