It is possible to use dhcp fingerprints to provide device category specific settings including lease times. This is not vendor specific, but a dhcp configuration.
Our observation is that many many many of our wireless devices are 'mobile appliances'. Mostly Apple today with android numbers increasing. The number of distinct android fingerprints is legion. The current trend toward common platforms may someday muddy the waters, but for the moment it is easier to reliably fingerprint Mac and Windows Notebook devices than any other category ... so I would propose a general reduction in wireless lease times with fingerprint based extensions for Notebooks. That said there are risks with shorter lease times. Specifically DHCP server load, increased network broadcast traffic, incompatible NAC attribution systems. increased log sizes (watch your siem license). I hesitate to suggest this if you do not have a functional system and network monitoring tool. I disagree with creating separate SSID / pools for device class because it is wasteful in an already fragile IP economy. Tested but unproven and without warrantee: If someone has their back against the wall and is interested in giving it a go... show this to your dhcp admin: If it works for you, let us all know the stats, send a donation to a food pantry. class "EXCEPTION" { match concat(pick-first-value(option vendor-class-identifier,"no-identifier"),"=",binary-to-ascii(10, 8, "-", option dhcp-parameter-request-list)); } subclass "EXCEPTION" "MSFT 5.0=1-15-3-6-44-46-47-31-33-121-249-43" { default-lease-time 7200; max-lease-time 7200; } also subclass MSFT 5.0=1-15-3-6-44-46-47-31-33-43 MSFT 5.0=1-15-3-6-44-46-47-31-33-121-249-43 MSFT 5.0=1-15-3-6-44-46-47-31-33-121-249-252-43 MSFT 5.0=1-15-3-6-44-46-47-31-33-121-249-43-4-0-2-21-20-232-25-48-24 MSFT 5.0=1-3-6-15-33-43-44-46-47-121-249 no-identifier=1-3-6-15-112-113-78-79-95-252 no-identifier=1-3-6-15-112-113-78-79-95 no-identifier=1-3-6-15-119-95-252-44-46 no-identifier=1-3-6-15-119-95-252-44-46-47 (there are a few more obscure entries but this will get you started) Randall Grimshaw rgrim...@syr.edu ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/.