With the adoption of the 802.3af protocol for Power over Ethernet (PoE) by the Institute of Electrical and Electronics Engineers (IEEE) last summer, vendors are developing new standard-compliant products. The proliferation of IP telephony and wireless access points are helping to drive PoE adoption,
according to some industry experts.
In addition to these two main drivers, innovations like security cameras, temperature, smoke and heat sensors and industrial automation are all ready to benefit from PoE capability.
Ronald Gruia, enterprise communications program leader at Frost & Sullivan Canada, warns rights-of-use fees mean PoE is still an expensive option, but 802.3af has helped vendors achieve some economies of scale.
“”Usage is increasing, but it’s still mostly the larger companies,”” says Gruia.
He sees Internet Protocol (IP) phones as a major market driving PoE adoption for enterprise customers, but it will take time to gain popularity among small and mid-sized businesses.
Gruia says vendors need to convince companies that PoE can provide a power backup for IP-PBXs, which is a mission-critical capability if power goes down.
“”If it happens and you don’t have a backup, the consequences could be pretty severe,”” says Gruia.
When considering adding a PoE capability to a network, Gruia says you need to consider how much you have to spend, find the right vendor and pay close attention to rights-of-use fees.
“”In some cases that can add quite a bit to the price,”” said Gruia. “”You need to find the right scheme to use for your network and the speed of your network connection.””
Cisco Systems claims to have given birth to PoE with their in-line power technology for IP telephony, and senior manager for LAN switching worldwide product marketing Steven Shalita says with the IEEE standard ratified, many more PoE applications will be coming down the road.
“”The standard really opens the door to a whole broad range of new network devices that you can connect and applications that can be deployed on the network,”” says Shalita.
He cites PoE enabled video cameras from Sony, a Canadian company building a PoE point of sale device, and adds Intel is working on a way to charge laptops using PoE.
Cisco has introduced a range of standards-based interfaces across their switching portfolio and now support PoE across the board.
When building a PoE-capable network, Shalita says, it’s important the local-area network switch has the capacity to support the generation and delivery of power to the devices you’ve deployed on your network, which could number in the hundreds.
The new standard supports up to 15.5 Watts of power per device, and with 100 devices connected to the network that’s as much as 1500 watts of power needed in addition to what’s required to run the switch itself. The second issue is wall power; it needs to have the capacity to support the power requirements.
“”There’s a wide range of power requirements that these devices have, so the ability of the switch to intelligently manage power delivery too maximize the power available is a key factor,”” says Shalita.
Shalita says Cisco’s PoE capable switches have the Intelligent Power Management feature to help address this. Most devices will need less than 15.5 watts; this feature ensures each device only gets the power it needs. It’s a problem similar to bandwidth over subscription.
“”Overcapacity costs a lot of money so you want to have that management ability,”” says Shalita.
At 3Com Corp. product marketing manager Doug Hyde says they’ve also developed PoE enabled products, including their Superstack 3 Switch 4400 PWR model.
“”It allows you to put the switch in the wiring closet and then drive power out on the Ethernet cable,”” says Hyde.
On the receiving-end, Hyde says they’ve implemented PoE across a number of technologies, including IP telephone products, wireless access points. They’ve also developed a small switch that fits in a wall outlet, their Intellijack Switch NJ105.
“”The concept is if you have a single Ethernet port in the wall you can put this switch in and instead of one wall port you have four,”” said Hyde. “”This Intellijack switch can be powered using PoE.””
