Presence/BLF (Busy Lampfield)

• Setting up Presence/BLF (Busy Lamp Fields)
• BLF with Cisco SPA525 IP Phone
• BLF with Grandstream GXP 21** series phones
• BLF with Grandstream GXP 2020 IP Phones
• BLF with Snom IP Phones
• BLF with Yealink IP Phones