Yesterday, I posted pics from my trip to Manhattan on Saturday. To my surprise I saw a lot of Avaya Red terminals despite Cisco selling VOIP sets like they are generic IP devices that corporate accounts pay little to none (allegedly) for.
The 8403 is a display-less set, designed for “walk up users” (to use a modern day cliche) or people who do not need functionality of a fully blown 8405 or 8410 terminal. The set supports up to 3 call appearances and if a user desperately needs features with indicators, one can program a feature (or two) but the set would act as a single appearance terminal.
It’s cousin set is the 7401, because it shares similarities to the 12 button personal features assignment. Someone can have up to 12 functions for abbreviated dialing, features, etc by hitting the Feature button and hit a single digit on the dial pad. There wasn’t a similar set till the late 2000s when Avaya released two sets, the 1403 and 1603 both for DCP and IP respectively, but ironically this require both to be run behind an IP Office, and not their enterprise PBX systems. It’s not to say one could reload firmware with the 1603 with some SIP firmware (which I believe it can work) and run it against Avaya’s SES services, and claim it to be a generic SIP set. These models furthers more irony because the 8403 was incompatible with Merlin systems anyways.