Terabit networks support transmission rates of at least one trillion bits per second and provide high bandwidth to meet increasing demands for data, voice, and video. Key requirements for terabit networks include scalability, flexibility, efficiency, improved network management, and rapid service recovery. Terabit network applications are characterized by unpredictable traffic demands and quality of service requirements. The document discusses technologies used to implement terabit networks such as dense wavelength division multiplexing for long-haul transmission, coarse wavelength division multiplexing for metropolitan areas, multi-protocol label switching, and a layered network architecture.

1. By- Vishal Kumar Gupta

2.  Terabit networks support transmission rates of at least
one trillion(10^12) bits/second (Tb/s).
 It provides the capacity and bandwidth to meet Increasing customer demand for data and voice
communications.
 To
support future Internet growth of high
quality video.
 To support e-Commerce application.

3.  Its proper design will lead to reduce The latency for Long Haul Network (LHN) traffic.
 The time needed for new circuit provisioning.
 Overall network management complexity.

4. The current market and service drivers give rise to some
unique terabit network challenges and requirements.
Chief among these are Network scalability,
 Flexibility, Efficiency and transparency,
 Improved network management & operations costs,
 Multi-protocol support,
 Rapid service recovery,
 Authentication, authorization and accounting.

5.  Terabit network applications are characterized by
unpredictable client traffic demands along with
Quality of Service (QoS).
 Traditionally, traffic planners could consider capacity
growth in three-, five- and ten-year increments.
 Today, the rapid and explosive growth in web video,
mobile messaging, wi-fi and wi-max applications,
means time frames as short as six months must also be
considered.
Thus, graceful scalability is a prime terabit
network requirement.

6.  From an end-user service perspective, terabit network
platforms must be very flexible, enabling clients to
increase service velocity on demand at any time, and
from any location.
 The networks must also efficiently accommodate a
diverse set of both differentiated service offerings (e.g.,
based on priority, resiliency, etc.), and wide-ranging
traffic characteristics (e.g. real-time traffic, legacy
protocols, high peak traffic, etc.).

7.  Today’s users not only want more bandwidth for their
money, they demand simpler and low-cost network
management & operations procedures.
Hence
terabit
network
equipment
suppliers must offer both operational
savings and support modular deployments,
and continuous growth.

8.  As new services are increasing-
Terabit Network is implementing “de-layered” and
transparent network infrastructure to support all
customer services along all locations.
 Providing reduced transmission and operations
overhead for a variety of protocols.
 Supporting OSI and TCP/IP both model.
 Supports Terabit Ethernet.
Terabit Network supports Multi-Service
protocol.

9.  Terabit Network is using RPR (Resilient Packet Ring)
technology to define the protocols for service recovery
with SONET/SDH network providers
 IEEE 802.17 Standard are accustomed to meet to a
maximum dual-ring-topology restoration time of 50
mSec.
 There is a possibility of even faster recovery times.
New terabit network technologies must
offer at least this level of protection or
better.

10. A key terabit network infrastructure issue is how to
provide the servers and security mechanisms to ensure
that no single person or resource can gain network
access without proper authorization.

11.  Terabit Network supports layered architecture model.
 The lowest layer supports multi-service access for all
types of data, voice, and video over a single packet-cellbased infrastructure.
 The benefits of multi-service access are reduced
OPerating EXpenses (OPEX)2, higher performance,
greater flexibility, integration and control, and faster
service deployment.

12. Figure 1: Layered Terabit Network Service Architecture

13.  CON is the heart of architecture which serves to
interconnect the multi-service access points with the
service platform.
 CON is designed with minimal complexity to reduce
costs, while still flexibly and efficiently supporting
multi-service transport because per-bit profit margins
is constrained by aggressive competition.
 CON packet forwarding overhead is greatly reduced
through use of Multi-Protocol Label Switching (MPLS)
technology.

14.  Internet Protocol (IP) packets have a field in their
header containing the address to which the packet is to
be routed.
 Traditional routing networks process this information at every router in a
packet's path through the network. *
But in Terabit Network When the data packet enters the first router, the
header analysis is done just once and a new label is
attached to the packet using MPLS.
 Subsequent CON MPLS routers can then forward
the packet by inspecting only the new label.

15.  MPLS classified CON routers into two categories1.
Label Edge Routers(LERs):


2.
High class packet classifiers
It apply and remove the requisite MPLS Labels.
Label Switch Routers(LSRs):


Core Routers
It performs routing based on Label Switching.
 MPLS technology supports both traffic prioritization
and QoS.
 It can be used to carry many different kinds of traffic,
including IP packets, ATM, SONET, and Ethernet.

16. The layered architecture includes following network
topologies-

17.  Personal Area Network (PAN)- Areas one to three
meters in extent which are serviced by wireless
technologies such as Bluetooth, Zigbee and Wireless
Universal Serial Bus (WUSB).
 Local Area Network (LAN)- It links user premises
to the first network node. In this network model LAN
will support 100Gbps.
 Metropolitan Area Network (MAN) Provide corporate connections inside the city.
 Fiber optics and Ethernet protocol is the favorite as
a MAC layer in use.

18.  Distribution and Transport Network (LHN) Regional Area Network (RAN) Used for localized services from a regional carrier, a
local enterprise, or a county or group of cities.
 RANs are needed for services that exceed geographic
boundaries such as those for international corporations,
national services, federal police networks, etc.

19.  Terabit Network is implemented using wave
transmission technology i.e. WDM.
 Wavelength Division Multiplexing (WDM) has
dominated fiber-optic transmission technology since
the development of tunable lasers.
 WDM technologies –
Dense Wavelength Division Multiplexing (DWDM) for
long haul transmission.
2. Coarse Wavelength Division Multiplexing (CWDM) for
metropolitan transmission.
1.

20.  Very precise and very costly.
 Supports hundreds of optical channels.
 Right technology for Distribution and Transport
Network inside the LHON (Long Haul Optical
Network).
 DWDM requires that optical channels be provisioned
on specialized nodes.

21.  Inexpensive and can be implemented on a variety of
physical media.
 Supports only 18 optical channels.
 Appropriate technology for PON local access
networks.
 CWDM can be easily implemented with point-topoint or point-to-multipoint topologies