End systems running ES-IS periodically transmit end-system hello
packets onto the LAN, thereby announcing their presence to other systems.
Similarly, intermediate systems (routers) periodically broadcast
intermediate-system hello packets onto the LAN.
The stations listen to these messages and populate their caches
based on the information contained in the hello packets.
Note that this protocol is generating traffic on the LAN whether
or not any data packets need to be transmitted.
This protocol is fully defined in [ISO/IEC-9542].
Copyright © 1999 by SAS Institute Inc., Cary, NC, USA. All rights reserved.