Tài liệu Private SONET Networks for Enterprise Customers docx

Overview
The LoopStar SONET product family enables an
easy, cost-effective way for large multi-site
enterprise customers and campuses to
interconnect each site or building using their
own fiber or leased dark fiber. Since large
enterprise customers typically have multiple
sites in a metro area, many of these sites need
to be interconnected, and connectivity to
corporate headquarters is often required as
well. However, building a physical mesh
network can become expensive, so enterprise
customers look for a cost-effective solution
that can interconnect their sites. Similar issues
apply to large government, educational,
military, or healthcare organizations that have
multiple buildings at a common site. Using the
LoopStar product family, enterprise customers
can build private SONET rings using a single
fiber pair to create a scalable, highly reliable,
and secure network.
Scalability
LoopStar SONET products scale from an OC-3
to an OC-192, and from a single 10BT to
multiple Gigabit Ethernet interfaces. In
addition, the ring topology and support
mechanisms that are available with SONET
networks enable enterprises to add a site or a
building to an existing network without
affecting the traffic on that network. With
support for 802.1QnQ, the LoopStar SONET

platforms provide for VLAN nesting, which
makes VLANs available that traditionally were
used for a corporate or an institution’s
backbone network. This also increases the
available VLAN address space, which could
become an issue in extremely large
organizations.
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LoopStar
®
SONET Access and Transport Solutions
Private SONET Networks for Enterprise Customers

Reliability
Network Protection
For customers who have existing SONET
networks, the merits of network protection in a
SONET network are well known. With LoopStar
SONET products, enterprise customers can extend
five 9’s reliability to their internal network.
Furthermore, these products support LAPS, UPSR,
and BLSR (1600 only), which means that
regardless of the topology chosen (ring or linear),
LoopStar products will provide an effective
solution. Since many enterprise applications have
hub and spoke architectures between the
corporate data center/PBX and each office,
SONET protection provides the most effective way
of safeguarding the network and a company’s

most valuable asset: information. In addition, by
using the LoopStar SONET products, the hub and
spoke architecture could be virtual over a
protected fiber ring or physical requiring linear
protection.
System Protection
While the LoopStar 800, 810, and 1600 all
provide network protection, the LoopStar 800
and 1600 also provide card-level protection for
both the optics and the cross-connects. In
business class networks, this results in optimal
uptime, due to the multiple layers of protection
involved in a SONET network. With protection for
both the cross-connect and optical cards, single
failure points are eliminated in the LoopStar 800
and 1600. This is due to the ability of the system
to independently switch the active cross-connect
card from the active optical module. With both
network and system-level protection, the
LoopStar 800 and 1600 provide maximum
reliability even in cases where multiple failures
may have occurred.
Electrical Protection
In addition to providing network and system-level
protection, the LoopStar 800 and 1600 provide
electrical protection on the TDM cards and
support RSTP on the common 8-port Fast
Ethernet card. For the TDM cards (DS1 and DS3),
one card can protect up to four other cards (n:1
with n=3 for the LoopStar 800 and n=4 for the

1600). This flexible protection feature makes
available slots that would have been reserved as
protection slots for other card types.
Security
Discrete Channels
Since the events of 9/11, security has become an
increasingly important aspect of enterprise
networks. In addition to reliability, SONET
networks are very secure by providing discrete
channels (STS-ns or VT1.5s) for specific customers
or services. Unlike a packet network where each
device accesses the header of each packet to
determine where the packet must be sent, a
SONET network sends the channels only to the
location where they are destined. Intermediate
transit nodes are configured to simply pass-
through the traffic without looking at it.
Therefore, for an external attack, a hacker must
be able to passively tap into the optical signal
(easy to detect), decode the SONET layer to get
into the frame containing the Ethernet traffic,
and then decode the Ethernet traffic. This is
virtually impossible if virtual concatenation is used
because packets are broken up and sent across
different paths to the destination node. Even if an
external hacker could get access to the packets,
the hacker would still need to gain access to the
provisioning system and redirect traffic by
reconfiguring the cross-connects, which would
create a series of alarms.

In-Band Management
Unlike data networks, SONET networks use an in-
band channel called the Data Communications
Channel (DCC) for management purposes.
Although the management traffic is separate
from the production traffic, both types of traffic
go over the same fiber. Typically, the
management traffic from each SONET network
element is configured to go through a Gateway
Network Element (GNE), where it is handed off
via a management Ethernet port. Since the
LoopStar products implement IP over the DCC,
each node is capable of being reached internally
over the corporate network. For this reason, the
IP address of each LoopStar product is located
behind the IT management firewall for protection
from internal and external attacks.
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LoopStar
®
SONET Access and Transport Solutions
LoopStar
®
SONET Access and Transport Solutions
Private SONET Networks for Enterprise Customers
2
www.adc.com • +1-952-938-8080 • 1-800-366-3891
Secure Access
As mentioned above, each LoopStar product has
an Ethernet management port; however,

generally, only one of the nodes acts as the GNE.
The remaining Ethernet ports on the network
elements remain unused. To prevent
unauthorized access, a hacker must get the user
name and password. It is also possible to place
the network element inside a locked cabinet at
each site. In this case, the system provides alarm
contact closures that would alert IT management
as soon as someone entered the cabinet.
Multi-Network Support
The LoopStar 800/1600 can provide an additional
level of security that is unavailable to traditional
data networking equipment. Using the multi-
ADM feature, a single SONET node can support
multiple physical networks. This provides
enterprise customers with the ability to separate
traffic from different departments without having
to use data networking technology such as
VLANs. Having different networks at the physical
layer prevents security issues such as MAC
address leakage between VLANs from occurring.
Summary
With the advances in Ethernet over SONET
technology and the ability to deliver traditional T1
services, the LoopStar SONET Access and
Transport product family offers an effective
means of transport for enterprise and institutional
organizations. This is especially applicable in
government institutions where the IT department
is set up as a cost center and owns the fiber or

leases dark fiber in order to provide connectivity
services for voice and data to other departments.
The LoopStar SONET platform provides cost-
effective, scalable, reliable, and secure
transmission between buildings or sites within an
enterprise or institutional organization.
9/05 • 1339239
LoopStar
®
SONET Access and Transport Solutions
LoopStar
®
SONET Access and Transport Solutions
Private SONET Networks for Enterprise Customers
3
www.adc.com • +1-952-938-8080 • 1-800-366-3891
ADC Telecommunications, Inc., P.O. Box 1101, Minneapolis, Minnesota USA 55440-1101
Specifications published here are current as of the date of publication of this document. Because we are continuously
improving our products, ADC reserves the right to change specifications without prior notice. At any time, you
may verify product specifications by contacting our headquarters office in Minneapolis. ADC Telecommunications,
Inc. views its patent portfolio as an important corporate asset and vigorously enforces its patents. Products or
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1339239 9/05 Original © 2005 ADC Telecommunications, Inc. All Rights Reserved
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