OSI Model

IT/242

Describe the open systems interconnection (OSI) model and how it relates to a network in 200 to 350 words. Include answers to the following:

• On which layers of the OSI model do WAN protocols operate?
• What are some of these protocols?
• On which OSI layers do switches and routers operate?
• If routers reside at more than one layer, what is the difference between OSI layers?