Conformance Testing of Non-PoE Devices in a PoE Enabled Network

Chodankar Deepak Pandurang, Goa College Of Engieering, Goa

POE- Power Over Ethernet, MIDSPAN, ENDSPAN, Power Source Equipment, Powered Device, UN-shielded Twisted Pair, Keystone, structured Cabling System

Ethernet for Data transfer in Computer Networks is ubiquitous. However some recent advancements in DC Powering have enabled transporting power and data simultaneously, over the same Ethernet cables. This technique is known as Power over Ethernet (PoE). However there are few challenges though, the first and the foremost being that of operational safety of the devices which are not PoE compliant. It needs to be noted that IEEE 802.3af standard specifies a 15W of PoE power at 48Volts DC which if connected to an incompatible device, may end up damaging it, permanently. Hence it is important that a PoE Equipment is tested and confirmed that it allows for safe and reliable operation of non-compliant devices. Failure to confirm this may have a catastrophic impact on the network that could range from a network crash to an imminent fire hazard. This paper discusses important tests which need be performed to ascertain that the PoE equipment being connected in the network will allow for safe and reliable operation of incompatible or legacy network devices. A LTSPICE simulated PoE network has been considered to carry out these various tests as well as for the verification of the safety features incorporated in the PSE-PD combination and its compliance to IEEE 802.3af standard. The observations and results are tabulated and conclusions are drawn.
    [1] IEEE Std 802.3-2015 IEEE Standard for Ethernet- (Approved 3rd Sep, 2015 by IEEE SA Standard Board) Section TWO, Subsection 33 – Data Terminal Equipment (DTE) Power via Media Dependent Interface (MDI) [2] Linear Technology LTC 4274 A/C Single PoE/PSE Controller, LT 0715 Rev D 2011 [3] Linear Technology LTC 4265 IEEE 802.3 at High Power PD Interface Controller With 2-event classification Recognition LT0714 Rev B [4] Linear Technology LTSPICE IV User Guide – 2011 [5] WP_Shieldadv Advantages of using Shielded Cabling Systems to Power Remote Network Devices Rev B 6/13. [6] ISO/IEC 11801, “Information Technology” Generic Cabling for Customer Premises – 2002. [7] Valerie Maguire WP-DeMystifying Cable De-Mystifying Cabling Specifications From 5e to 7a – Rev F 5/11 [8] ISO/IEC TR 29125 “Information technology – Telecommunication Cabling Requirements for Remote Powering of terminal Equipment “2010. [9] Siemon White Paper - Zone Cabling and Coverage Area Planning Guide-2015 [10] Cisco White Paper – Cisco Digital Building Solution [11] Design Lights Consortium White Paper – PoE Lighting Systems
Paper ID: GRDJEV02I060032
Published in: Volume : 2, Issue : 6
Publication Date: 2017-06-01
Page(s): 64 - 71