Page 10
www.us-
tech.com
TechWaTch
The Passive Optical LAN: Providing Enterprises Mega Improvements in Network
Performance and Flexibility By Ed Sullivan
E
nterprise networks around the world are becoming progres- sively choked by the integra-
tion of bandwidth-hungry Internet- based applications. The growing us- age of streaming video content, inte- gration of digital voice services into the LAN, video conferencing and oth- er online activities not only con- tribute to the enterprise bandwidth dilemma, but also can pose signifi- cant security issues to conventional copper-based networks. With dramatically increasing
demand for bandwidth among user populations, many enterprises are finding the right data communica- tions solution is the Passive Optical LAN (POL). Essentially composed of point-to-multipoint fiber conducted through unpowered splitters, POLs are telecommunications networks that enable enterprises to simultane- ously converge multiple services such as data, VOIP, video, building security and management services and wireless devices. Also, compared to conventional
copper-structured cabling, POLs of- fer significant “green” incentives, a much smaller cabling footprint, and
a future-proof architecture that can grow with bandwidth demand.
Basic Benefits of POL “Many users of fiber optic cable
services such as Verizon’s FIOS™ in their homes or businesses are, per- haps unknowingly, quite familiar with the basic benefits of the POL,” explains A.G. Melson at Optical Ca- ble Corporation (OCC), Roanoke, VA. “Because these cable TV
providers have fiber optic backbones that can travel great distances with- out a degradation of signal (which oc- curs with copper-based cable), they can deliver higher bandwidth servic- es such as high-definition TV, high- speed Internet, and digital tele- phone, individually or bundled,” Mel- son explains. OCC is a manufacturer of a
broad line of data communication ca- bling and connectivity solutions. In the POL arena, the company offers specifically designed products to cov- er the entire network “signal path” from the OLT (optical line terminal) all the way to the ONT (optical net- work terminal) next to individual users’ workstations or desktops.
Melson likens POL technology
(also referred to as a Passive Optical Network, or PON) to a FIOS-type ar- chitecture routed throughout a build- ing or enterprise campus, rather than a residential neighborhood. The single-mode fiber network backbone is connected to splitters, each of which will provide fiber to 32 “cus- tomers.” In total, a single POL can be
connected to hundreds or even thou- sands of individual users, providing them with a multitude of enterprise and outside telecommunications ap- plications.
Conventional LANtoBecome POL Industry suppliers project that
in the not-too-distant future between 10 and 30 percent of population of conventional LAN architecture will move toward POL. The typical POL network will serve 200-plus users. The benefits of POL are many,
and should encourage enterprises such as universities, hospitals, corpo- rate campuses, and multi-dwelling units — any facilities with relatively high-density populations of users — to install or retrofit this architecture.
Technical and Economic Advantages
“The performance benefits of
POL are substantial,” says Dr. Ian Timmins, Vice President of Engi- neering, Enterprise Connectivity Products at OCC. “Fiber offers high- performance bandwidth over much greater distances than copper-based infrastructures. When you install a POL you’re really setting yourself up with a highly reliable infrastructure that’s far more future-proof than any conventional copper-based network.” POL over single-mode fiber rep-
resents a major bandwidth upgrade for enterprise networks currently op- erating with 1or 10Gb to the desktop. Also, single-mode fiber reach for POL is in the 10-20 kilometers range, whereas conventional copper archi- tecture is typically limited to a 100- meter channel. Timmins adds that CapEx and
OpEx advantages are significant as well. POL is significantly less costly than copper-based LANs. Invest- ments in wiring closets and associated electronics and are eliminated as well as climate control costs. Installation costs are reduced because the fiber ca- bles are less expensive and easier to install. POL flattens the LAN by re- ducing the number of switches and routers on a network by connecting devices to a single switch rather than separate switches. Reaching multiple users with each fiber gives POL flexi- bility not present when compared to copper-based LANs. This architecture also addresses
the “green” initiative and saves on costs at the same time. There is no electric power requirement for elec-
tronics between the OLT and users. The need for a telecommunications room, or wiring closet, is replaced with zone enclosures, eliminating the need for a closet cooling system while reducing power consumption. POLs are also considerably more
secure than legacy Ethernet net- works. They are free from cross talk and interference. Conventional Ether- net LANs emit electromagnetic sig- nals that can be intercepted. POLs, which contain all optical fiber, do not. They are non-flammable and require no EMI or FRI shielding. Plus, the POL supports security mechanisms such as AES (advanced encryption standard) 128-bit encryption.
Ease of Installation
Generally speaking, POLs are easier to install because they are simpler, consisting mainly of fiber optics pass- ing through splitters that deliver services to the user faceplates (to which their equipment is attached). Also, pathway space requirements, such as the headspace over drop ceil- ings, are reduced significantly. A typical POL “zone” configura-
tion is composed of an MDF (main distribution frame) that runs fiber to a zone distribution enclosure that is typically mounted in the ceiling. The zone distribution enclosure contains splitter cassettes (1 to 32 splitters) from which fibers are run to the user via ONT (optical network terminal). A copper patch cord connects the ONT to the user’s Ethernet NIC (net- work interface card). Some suppliers have developed
proprietary POL devices to enhance ease of system installation. For ex- ample, OCC has developed two ceil- ing-mount zone enclosure versions. A standard model, which supports up to three 1-32 splitters, is 8-1/2-in. deep. A low-profile model, which is only 4-in. deep, is available for areas where there is less headroom above drop ceilings (due to air conditioning ductwork, fans etc.). The latter mod- el supports a single 1-32 splitter. The company also offers a small
wall-mount enclosure for a 1-32 split- ter for enterprises that require some additional ports after the initial POL installation. This model has remov- able adapter plate components for easier installation. For retrofit installations, OCC
offers a full line of rack-mount, pre- configured enclosures. “These are available for those retrofit installa- tions where rack space is already in place, and the customer would prefer to continue using it,” Timmins ex- plains. “However, with retrofit POL solutions, having existing telcom
closet space is unnecessary.” Contact: Optical Cable Corpora-
tion, 5290 Concourse Drive, Roanoke, VA 24019 % 800-622-7711 Canada % 800-443-5262 fax: 540- 265-0724 Email:
info@occfiber.com Web:
www.occfiber.com r
March, 2015
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100 |
Page 101 |
Page 102 |
Page 103 |
Page 104