IS-IS
 
 
- “Intermediate System to Intermediate System”
- Selected in 1987 by ANSI as OSI intradomain routing protocol (CLNP – connectionless network protocol)
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- Based on work by DEC for DECnet/OSI (DECnet Phase V)
 
- Extensions for IP developed in 1988
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- NSFnet deployed, its IGP based on early ISIS-IP draft