P-OTN:

Packet Optical Network Transformation

Infrastructure Market in Turmoil

When it comes to telecommunications, the vision for
the future is undisputed: multiple next generation
services based on Internet Protocol (IP) delivered over
a fully packet based network. What is in contention is
how to get from here to there.

There are currently a multitude of technology options
for carriers and vendors to choose between from
extension of existing SONET/SDH networks with
GFP/VCAT/LCAS to MPLS, VPLS, T-MPLS/MPLS-TP,
PBB, PBB-TE, OTN etc.

Amidst this turmoil, some points are becoming clear;
the preferred interface is Ethernet, as it provides the
best scalability from 10 Mbps to potentially 100 Gbps,
while optical transport is the only economical means
of meeting the current and expected growth in
bandwidth demand.

Hence the interest in merging packet and optical
technology into a converged solution.

Some commentators observe that “packet optical” is
the hottest trend in optical networking in 2008.

This white paper sets out to examine the packet
optical marketplace, the market drivers and service
applications that are placing new requirements on
carrier networks. In turn, these new network
applications place new requirements on systems
and technology implementations, which are also
described.

In this paper, TPACK addresses the “P-OTN” or
Packet Optical Transport Network market. That is to
say, packet transport networks built upon the ITU-T's
established set of OTN network standards such as
G.709. P-OTNs can be built using multiple optical,
Ethernet and/or MPLS network elements, including
fully converged elements which Verizon, for example,
has termed “P-OTP” or Packet Optical Transport
Platform.

From this strategic perspective, P-OTN encompasses
the multitude of different system descriptions that
have recently appeared, including “PONP”

, “POTS”

“CET”

, and others less commonly used such as

“OPT”

. These descriptions and possible distinctions

are explained later in this paper.

As network and system architects work to define
flexible, cost-effective and future-proof designs, it is
already clear that one size of system solution will not
fit all network circumstances. Indeed, mainstream
industry opinion holds that further evolution and
incorporation of new standards from ITU-T, IEEE and
IETF will be a defining characteristic of P-OTN over
the coming years.

In chasing such a moving target, the risk for both
network and system implementers is twofold:

• Freezing a design too soon means early

obsolescence, wasted effort and stranded
investment, since interoperability with forthcoming
solutions is compromised;

• Jumping forwards too far by adopting pre-

standardised approaches, or approaches that fail to
be adopted by the wider market, carries exactly
the same consequences.

In both scenarios, carriers cannot achieve the
economy of scale they need for profitability. Whilst
for system suppliers, playing a waiting game is
commercial suicide in today's cut-throat market
regime - thus the tightrope must be walked between
advancing too quickly, and being left behind.

TPACK has built its business by helping systems
houses to walk this line: allowing them to push their
solutions forwards while building in the flexibility
required for inevitable future changes. A partner
white paper

“SOFTSILICON for Flexible Packet

Transport” explores TPACK's approach and the
benefits that manufacturers can gain, ensuring that
they stay afloat in this time of market turmoil and
packet network transition.

2) PONP: Packet Optical Networking Platform
3) POTS: Packet Optical Transport System
4) CET: Carrier Ethernet Transport
5) OPT: Optical Packet Transport