The ELAN is used for inter-processor messaging i.e. call processing and signalling between CS1000 components such as Call pilot, symposium, signalling servers etc. and as such such be in it's own VLAN as it is very time sensitive and will react badly to excessive broadcasts. Only CS1000 components should be in this VLAN and NOTHING else. The CLAN is not time sensitive and things such as real time displays, admin terminals and pretty much anything else can reside in it.