How to Understand PoE and PoE+ Switches

Power-over-Ethernet (PoE) is the technology that allows network switches to transmit power and data through an Ethernet cable at the same time. PoE switch streamlines both of the processes of powering and providing data to the device, which makes it a straightforward and reliable device for home network and small enterprise application. This article describes two types of PoE (PoE and PoE+) that are commonly used and provides information on what types of PoE can be used according to different applications.

 

PoE Versus non-PoE Technology

 

Power over Ethernet technology facilitates powering a device (such as an IP phone, IP Surveillance Camera, or NVR recorder) over the same Ethernet cable as the data traffic. Figure 1 shows an Ethernet Network with IP camera, PoE Switch, NVR recorder and Wireless router. Compared to non-PoE devices, PoE devices feature with flexibility that allow you to easily place endpoints anywhere in the business, even places where it might be difficult to run a power outlet.

 

PoE Versus PoE+ Technology

 

PoE was first defined in the IEEE 802.3af standard. PoE devices utilize PoE standard, which can provide up to 15.4W of DC power to each port. A later standard, IEEE 802.3at, known as PoE+, increases the amount of power to 30 W. The major difference between 802.3af (PoE) and 802.3at (PoE+) is that PoE+ PSEs can provide almost twice as much power over a single Ethernet cable.

 

Can PoE+ devices work over PoE Ports, Or vice versa? The PoE+ standard provides support for legacy PoE devices, meaning that an IEEE 802.3af powered device (PD) can operate normally when connected to IEEE 802.3at (PoE+) power sourcing equipment (PSE). PoE+ PSEs can supply power to both PoE and PoE+ PDs. However, as PoE+ PDs require more power than PoE PSEs can provide, PoE PSEs can only supply power to PoE PDs.

 

PoE Switch Or PoE+ Switch

 

Whether to use PoE or PoE+ switch for your network, you need to calculate your required power budget carefully for all of the PDs you plan to connect. PoE+ IEEE 802.3at devices can supply a maximum of 30 watts per port, while PoE IEEE 802.3af devices can supply a maximum of 15.4 watts per port. However, some power is always lost over the length of the cable, and more power is lost over longer cable runs. The minimum guaranteed power available at the PD is 12.95 watts per port for PoE and 25.5 watts per port for PoE+.

 

For most endpoints, 802.3af is sufficient but there are devices, such as Video phones or Access Points with multiple radios, which have higher power needs. It’s important to point out that there are other PoE standards currently being developed that will deliver even high levels of power for future applications. Optical switches have a power budget set aside for running the switch itself, and also an amount of power dedicated for PoE endpoints.

 

fiber-mart.com PoE Switches

 

fiber-mart.com POE switches can supply power to network equipment such as weather-proof IP cameras, AP and IP telephones. They are featured with high flexibility, high stability and high resistance to electromagnetic interference. All fiber-mart.com PoE switches come with a one-year limited warranty, including any quality problems during the free maintenance. The following above shows 1G PoE Switch with 24 1000BASE-T and 4 SFP ports.

How to Connect CAT5e and CAT6 Cable

by www.fiber-mart.com

Thus far in past blog articles we’ve focused on the different types of networked infrastructures, the need for UTP (Unshielded Twisted Pair) cable, the various do’s and don’ts associated with the handling and installation; and how UTP, as a balanced line cable, is able to reject RFI  (Radio Frequency Interference) and EMI (Electromagnetic Interference). In this blog article we’ll discuss the termination of UTP at the head end as well as the plugs and jacks at the edge of a network.

 

If you recall, in a past blog post, we discussed where the standards that fuel and control the implementation of network Ethernet cabling and all connected devices come from. If you recall, it is the Electronics Association/Telecommunications Industries Association, also known by its acronym, EIA/TIA. The standard itself that largely controls how devices are wired is the “Commercial Building Telecommunications Standard.”

 

The two primary UTP cable types that commonly are used in computer networks are CAT5e (Category 5e) and CAT6, both of which are balanced lines. They support 10/100 Mbps–up to 1 Gbps and 10 Gbps respectively.

 

If you are looking for cable for security purposes, such as access control and video surveillance, CAT5e will usually do the job. However, if you intend to use it for 4K and 8K, then perhaps CAT6 is a better choice, especially if you want to future-proof your installation. In addition, an important thing to remember is to match the jacks, plugs, patch panels, and other connected devices with others that are rated the same as the cable in use.

 

Making the CAT5e or CAT6 Connection

 

Whether it’s CAT5e or CAT6, there are 4 pairs of conductors that you need to contend with (see illustration). They are:

 

Pair 1: White-Blue/Blue

 

Pair 2: White-Orange/Orange

 

Pair 3: White-Green/Green

 

Pair 4: White-Brown/Brown

 

These four cable pairs, be it CAT5e or CAT6, connect to plugs and jacks according to two connection standards known as T568A and T568B. The latter also is referred to as the AT&T standard.

 

The primary difference between the two is in how positions 1, 2, 3, and 6 are wired (see illustration) with regards to Pairs2 and 3. Using the T568A standard, Pair 2 connects to positions 3 and 6 while Pair  3 connects to positions 1 and 2.Using the AT&T configuration, Pair 2 connects to positions 1 and 2 while Pair 3 uses positions 3 and 6.

 

Does it matter which standard you use? Not really, but once you start using a specific connector configuration on a job,you must continue using it throughout the project. With that said, if you’re adding to an existing installation, you must check the existing connections to determine which configuration that the installer used. Most of the time you will use T568A because it’s used by more techs than the T568B, even AT&T techs.

 

When making a connection using either configuration, remember to do so without unduly untwisting each wire pair. If you do, it will adversely affect the performance of the wire in general. Keep the integrity of the twist as close to the plug, jack, patch panel, etc., as possible to maintain the CAT5e or CAT6 performance.

 

There are two methods of connecting Category 5e and Category 6 cable to plugs, jacks, patch bays, and other devices. The T568A is the most commonly used configuration today.

what are differences of bare fiber,loose tube and tight buffer tube

by www.fiber-mart.com

Bare fiber

 

From the fiber production process, which the composition of the fiber from the inside out: the core, cladding, a coating, and secondary coating. Optical signals in optical fibers are using light of the principle of total reflection. The glass fiber is the main channel of transmission of optical signals, the cladding is used to reflect the optical signal, and the coating is to protect the fragile core. Bare fiber means it has not been coated fiber.

 

Loose tube

 

The loose tube is outside layer of protection for fiber. Because of fiber’s very fragile, easily broken, which the production will be one or more optical fibers placed inside the loose tube, and then fill in the ointment. Then, coupled with strengthening the core which used to increase the fiber optic cable  strength and the outer sheath, such as aluminum foil and polyethylene jacket, became a fiber optic cable.

 

Tight buffer tube

 

With tight buffered single mode or multimode optical fiber secondary coating structure is called tight buffered optical fiber. The second set directly on the bare optical fiber is made of a coated optical fiber plastic, such as PVC, PVDF, LSZH, etc. It is the basic components for the manufacture of a variety of indoor cable, which can also be used alone. The tight buffer fiber can be used directly in pigtail for the connection of various types of optical active or passive components, instruments and terminal equipment connections.