Instruction: Parse the product information to locate the target attribute, and then provide the extracted value of the target attribute and its source in the output, specifying None if the attribute is not present.

Input:
Product title: Buffalo 16-Port Desktop/Rackmount Gigabit Ethernet PoE Web Managed Switch (BSL-PS-G2116M)
Product description: Buffalos 16-port Rackmount Gigabit 802.3at PoE Web Managed Switch offers an easy way to extend your business network with fast gigabit speeds and simple, cost-effective Power-over-Ethernet (PoE). Featuring sixteen 802.3at gigabit PoE Plus ports with up to 30W of power per port, it provides sufficient power for high energy consuming devices with a total power output of 180W on the switch. Easily power dual band access points, IP surveillance cameras and VoIP and video phones, including newer models that require more power than before. The durable metal chassis is rack-mountable and equipped with holes for wall-mounting and rubber feet for easy placement on a desktop. Performance minded features such as VLAN, STP support, power cyclable PoE ports, 802.3af compatibility, Jumbo Frame support, 802.1p QoS, USB flash recovery and eco minded operation make the 16-port Rackmount Gigabit 802.3at PoE Web Managed Switch a perfect solution for your converged network.
Product feature: Cost-effective Power-over-Ethernet (PoE), PoE PLUS 802.3at, Vlan Support, Jumbo Frame Support, STP Support, Power Cycling PoE Ports, Quality of Service, Easy Web Configuration
Product brand: BUFFALO
Target attributes: Switch Type
Answer: attribute: switch type
value: managed
source: product description
attribute: switch type
value: managed
source: product title