Creating Virtual Fiber Networks

Posted: 2/2003

Creating Virtual Fiber Networks

By Khali Henderson

Seeking to infuse flexibility in the
transport infrastructure, startup vendor Meriton Networks Inc. is set to unveil
its optical add/drop switch (OADX), which integrates optical transmission and
switching, with capability to create intelligent virtual fiber networks, more
commonly known as optical virtual private networks (VPNs).

"We’ve seen [the evolution from
static to dynamic networks] before with ATM," says Robert Gaudet, director
of product management for Meriton. "We think history can be repeated."

OADX enables two modes of
partitioning: Virtual backbone networks (VBNs) and virtual service networks (VSNs)
(see diagram below).

VBNs are subsets of the physical
OADX network. A service provider can partition the physical resources of the
network, such as fibers, cards or ports, for use by a single customer. The 8600
NMS integrates element and network management functions, and automates common
operational tasks, including setup, maintenance and teardown of optical paths.
Leveraging the 8600 NMS capability to partition resources based on users and
groups, the 9200 Optical Service Manager can create private wavelength networks.
Meriton’s 9220 Virtual Fiber Manager application allows the subscriber to manage
these resources directly from their own location, via a GUI or CORBA management
interface.

VSNs allow customers to set up, tear
down and monitor their wavelength services. The 9220 VFM lets the customer
modify its lightpaths without having to call their service provider. For
example, the wavelength can be connected to a SAN provider during the day and to
its data center at night.

"The difference [between VBN
and VSN] is in how much network detail is provided," says Gaudet.
"With VBN, you see connectivity and topology. VSN is more abstract — no
topology, just connectivity and the ability to move it around."

Gaudet says release one, 7200 OADX,
which governs the physical network, is in lab trials in Canada and the United
States and in field trials in Europe. It was expected to be commercially
available in January. Release two, which enables VBNs and VSNs, is expected in
the second or third quarter. Trials are scheduled for early second quarter.

Gaudet says North American carriers
are interested in the capex reduction potential of the OADX, which collapses
optical muxing and switching into a single network element. Europeans, on the
other hand, are looking at new revenue opportunities, he said.

New revenue opportunities also are a
byproduct of the Intelligent Network Control Plane (INCP), rolled out in October
by startup Elematics Inc. INCP attempts to bridge the divide between different
vendors’ optical equipment; among WDM, SONET and TDM-based network elements;
between existing operational support systems; and even between disparate
operators’ networks.

Elematics CEO Clive Cook says the
idea grew out of the need for a system that could control the physical trading
of bandwidth. Elematics’ co-founder and chairman is Alex Mashinsky, who is known
for founding Arbinet-thexchange Inc., where he now serves as vice chairman.
"As we gathered feedback it became evident that traders needed a way to
cross networks and vendors," he says. "It evolved into a broader
solution–for every carrier, not just those that are trading. There is no
automated or easy way to do this."

Because it allows for end-to-end
connectivity across single or multiple carrier networks, the middleware opens
the door to new services, such as Layer 1 VPN or optical VPN, which connects
optical backbone services.

Cook explains the INCP takes
information from the switch and propagates information to carrier OSS systems,
and a subset of that information to its wholesale customer (see diagram below).
"It is effectively enabling retail carriers to treat off-net services as an
extension of their own network," he says, explaining they can see more than
whether the connection is up or down, including topology and performance
metrics.

Cook adds that while the product
enables switched waves, demand has not yet taken off for that type of service.
"Carrier interest is not so much on dynamic control. They are still in the
mode of point-to-point connections and are more interested in monitoring and
visibility."

Cook says optical VPN service is
gaining interest among retail carriers. The retail providers now are introducing
Elematics to their wholesale carriers that need the capability to make optical
VPN possible.

Analyst David Gross from CIR is less
optimistic, however. "I don’t know what’s gained by going to Layer 1,"
he says, noting Layer 3 VPNs already fill the need and that limited availability
of optical services cannot support VPNs to any great extent at this time.

Denis Gallant, CTO for Meriton,
notes that carriers have progressed from deploying WDM systems in a
point-to-point configuration to a ring-based system. "The next evolution is
to migrate from rings to mesh network architecture," he says. "With a
mesh, the structure is in place for offering OVPNs."

Intelligent Virtual Fiber Networks
Meriton Networks’ optical switch enables carriers to offer VBNs, which
are subsets of the physical network, and VSNs, which allow customers to set up,
tear down and monitor their wavelength service.
Source: Meriton Networks

Optical VPN Partitioned View
Using Elematics’ Intelligent Network Control Plane, carriers can offer
wholesale customers a partitioned view into their network.
Source: Elematics