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Table of Contents.....................................................................Page
No.:-
Introduction & Objectives of the
SONET………………………………………………………………………...…4-5
SONET History & the Current
Techniques……………………………………………………………………….5-6
SONET Protocols, Network Topologies&
Configurations ....................................
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10
Comparision of the SONET technology with other
technologies........................................................................................................11
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12
Benifits of the
SONET...............................................................................................................13
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14
Disadvantages of the
SONET
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15
Protocollayers in the SONET.................................................................................16
Operation, Maintenance &
Administration
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16
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17
Wide Area
Network...................................................................................................................18
Overview of the WAN
technology
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19
WAN devices...........................................................................................................19
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Synchronization
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20
SONET
Equipments
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21
SONET Standards
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22
Next Generation of the
SONET
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23
SONET Hierarchy
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24
Deployment of the
SONET
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24
SONET Signals
.
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25
The Basic Unit of Transmission in the
SONET .............................................................................................
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26
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29
Cost
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30
Conclusion
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0
3
Acknowledgement
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31
Refrences
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32
Turn it in Report…………………………………………………………………33
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Synchronous Optical Networking
(SONET)
INTRODUCTION & OBJECTIVES:-
Introduction to SONET:-
We know that in the modern world, an organization’s are increasingly looking forward for the
result of the character knowledge that flows through their communication networks. These
necessities require more effective management & identity of such knowledge flows. The tool for
identifying social networks & its structures a communication is needed. Again, the flow of such
knowledge in which social networks communicate is also to be analyzed. Thus, a research tool to
analyses such communication in course sites that use social networks was motivated to be
created. This tool was SONET. It gives the data, sound and video through the same service as an
union of technology in combination. We know that social networks are like graphs. They use
nodes to constitute parties & edges to constitute the communication links. In the same way,
considering knowledge management, here the nodes constitute people whereas the associates
constitute the transfer of knowledge from person to person.
SONET falls under Physical Layer of OSI model defining the interface standards. This standard
is the hierarchy is the of interface rates. It allows data streams to be multiplexed at the different
rates. Its implementation has helped the communication carriers in the world to interlink their
living fiber optic systems & the digital carriers. Optical Carrier levels from 51.8 Mbps to 2.48
Gbps can be established by the SONET.
SDH is the international equivalent of SONET, which is standardized by the ITU. Also SONET
network components can obtain signals from different forms of facilities like DS1, DS3, LAN,
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MAN, WAN, ATM, Internet & a variety of network topologies. Moreover, it is known that even
the SDH signals can be connected to SONET and vice versa.
Objectives of SONET:-
Some of the objectives of the SONET are given below:-
To visualize & recognize the type of communication that occurs in a network.
Recognize the knowledge hubs not contributing to the community.
For synchronous networking
To transport new services like the ATM.
For grooming
For the enhancement of OAM&P
To arrange multi-point
To introduce mid-span meet
For the standards-based survival rings
HISTORY & CURRENT TECHNIQUES:-
History:-
It is known that the SONET was primitively developed for the populace telephone networking.
Formerly in the 1980's, the break apart of the AT&T in United States generated various regional
telephone companies. However, the organizations soon faced hardships in the networking with
one another. Fiber optic cabling had so soon persisted for a far distance voice traffic
transmission. The living networks was unnecessary costly to develop & hard to extend for a
lengthy haul data & video traffic.
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Thus, the American National Standards Institute (ANSI) successfully intended SONET as the
new standard for these applications. SONET was founded in the mid 1980s by the Exchange
Carriers Standard Association (ECSA) to the American National Standards Institute (ANSI). It is
considered as the standard for the fiber optic networks which are used widely today all over the
world. It allows multiple vendor products & technologies defining physical network interfaces.
We know that the very first fiber optic network was creditworthy for equipment, procedures, line
codes, maintenances etc. The need of standard that supports in matching equipment from
different vendors is being opted by the users from different companies as well as countries like
Korea, Brazil, Hong Kong, Canada, Japan etc. Like Ethernet, SONET provides an interface layer
technology. This is because the SONET also behaves as a carrier of the multiple high level
application protocol.
Current Techniques:-
SONET is presently a grouping of physical layer constraint
Based on the signaling speed hierarchy Synchronous Transport Signals (STS), SONET is just a
group of physical layer requirements. It also demonstrates the sub level of the STS-1 signals.
STS-1 formats can also be subdivided into smaller segments called virtual tributaries. We know
that these virtual tributaries are the synchronous signals which are used for the transporting the
low speed transmission.
Pointers are a concept that is used to compensate frequency & phase variations. These pointers
allow the transporting of the synchronous payload envelops across the boundaries transparently.
The payload envelops may be either STS or virtual tributaries. They are between the nodes along
with the separate network clocks with same timings. It is known that to avoid data loss & delays,
the pointers are used widely.
This table down shows the contents of the list of virtual tributaries with their sizes.
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SONET PROTOCOLS, NETWORK TOPOLOGIES &
CONFIGURATIONS:-
SONET Protocols:-
We know different terms are used by the SONET to explain functions & features. Again, these
terms exaggerates their differences & create confusions too. It is known that the protocols are
highly multiplexed. The header is furnished in a complex way between the data. This helps the
capsuled data to own its own frame rate. The data is locked in a different rate than frame rate so
extra padding is allowed to the multiplexed data. Decision to allow extra padding in the most
levels of multiplexing has made the protocol more complex. Here, compared to the frame rate of
125 microseconds, the data sending rate is delayed by 32 microseconds.
SONET Topologies:-
Ring is the major deployment architecture of the SONET. Survivability is the major benefit of
the ring architecture. ASMs can be put in ring architecture. Rings are the most relevant
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architectures in SONET implementation due to its redundancy. Multiplexers can send signals
through the rings with no interruption even if the fiber is cut down.
Network Architecture:-
We know that the SONET has limited number of architectures which allows us for the protection
& enough usage of the bandwidth. Regardless the transmission speeds, the SONET connection
use two fiber optics.
Some of the network architectures of the SONET are:-
Linear Automatic Protection Switching:-
Linear Automatic Protection Switching (APS) is also known as one plus one (1+1) switching. In
this switching four fibers are included. Among which two of the fibers are working fibers & tow
are protection fibers each in both the directions. Here the switching is always based in the line
status. The switching may be in unidirectional or bidirectional.
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Unidirectional Path Switched Ring:-
Two path degree transcripts of the protected traffics are transferred to either direction across the
ring in Unidirectional Path Switched Ring (UPSR). Here a selector is placed at the egress node
which uses the copy identifying the copy that contains the maximum quality. UPRSs always sit
close to the network edge. They are called collector rings too. Total capacity of the UPSR is the
same of the line rate of the OC-N ring. This is because the data transmitted across the ring is both
directions are always the same.
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Bidirectional Line Switched Ring:-
Bidirectional Line Switched Ring (BLSR) can be divided into two parts. They are two fibers
BLSR & four fibers BLSR. BLSRs do not send path level copies from ingress to the egress same
as the UPSR. We know that an unsuccessful or sustenance action on one line cause protection
fiber which connects the two nodes needed to be employed rather than looping across the ring.
So, either multiple line failures or single node failures can be supported in four fiber ring. Total
bandwidth which BLSR supports is unlimited to that of OC-N so it can move traffic between
metropolitan regions too. BLSR serves as a collector ring. Thus BLSR are often deployed in
collector rings, inter-office rings so it is seldom in nature.
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COMPARISON WITH OTHER TECHNOLOGIES:-
Comparision with ATM:-
We know that ATM falls under the data link layer whereas the SONET is a physical layer
application of the OSI model. ATM uses layer one technology to transport services. The SONET
is the major technology in physical layer. This technology is commonly used by the ATM. There
may also be other examples of the physical layer containing WAN interfaces. The ATM follows
the fixed cell length technology whereas the SONET uses a frame based technology. The ATM
specified cells are added to the frames used by the SONET through which the ATM cells are
transported.
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Many companies including the government agents use ATMs. They can achieve a lot of leverage
using the SONET transport tecnhology. This combination of ATM & the high speed SONET
devices leads the customers to satisfy through the advantages of the SONET.
Comparision with FRAME RELAY:-
As the SONET is a technology with rotating rings, it cures mechanically in the happening of
failures. The rate of transfer in SONET begins with 155 Mbps & goes up to 9.95 Gbps. To
achieve the high speed, the SONET channels are multiplexed.
We know packets are used by the frame relays which are 64-1500 bytes in size. A flag is
assigned to the start & end points. Frame relays can transfer voice traffic & even video traffics. It
assists save the network bandwidth as well as to generate higher productivity of the network.
SONET has a high speed as it consist optical fiber. However, frame relay can’t gain speed
without the help of RBOC. Users of the frame relay are growing day by day. In the same way,
the frame relay supports the SONET to grow the bandwidth of their network.
Comparision with SDH:-
It is known that the SONET & SDH standards are both specified for the data transmission over
fiber optics. SONET is an American standard presented by the ANSI likewise SDH is the
international standard presented by the ITU. The main ingredient of SDH is the STM-1 likewise
the STS-1 is the major ingredient of the SONET. However, both the SONET & the SDH contain
the common OC-n that provides the midpoint meeting. OC-n signals are achieved by scrambling
the STS-n & STM-n signals. The SONET & the SDH will be incompatible if the SPE mappings
used are different.
BENEFITS OF SONET:-
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The SONET has become the well-known major technology in the market against the former
telecommunication technologies. This is because of its flexibility in configuration.
Some of the major merits of the SONET are provided as follows:-
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Grooming:-
Combination & separation process is exercised by the grooming in order to function in a high
efficiency rate.
Arrangement of multi-point:-
Point-to-point configurations can only be handled by the asynchronous systems. However, the
SONET handles multi point configurations as well as the hubs. These hubs support in deducting
the multiplex along with the de multiplex which supports in the traffic grooming.
Reduction of cables as well as DSX panel elimination:-
We know that DSX panels are the equipment of the asynchronous system. DSX panels are
intended to perform grooming in synchronous network electrically.
Enhancement of performance monioring:-
The SONET can switch the traffic automatically as it can sense the problems with the help of the
dual ring architecture.
Enhancement of OAM&P:-
The network vendors are excessively referred to Operation, Administration, Maintenance &
Provisioning (OAM&P) process. This is because of the availability of various network providers
have various products in the transmission network. OAM&P networks can be merged by the
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SONET. This will support the linking a connection to another that supports to save budget which
connects individual networks.
Optical Interconnection:-
We can summarize all the advantages of the SONET in the form of compatibility, flexibility,
technology & economics. STS as well as the optical carrier (OC) needed for the transmission in a
fiber optic cabling is included in the SONET.
DISADVANTAGES OF SONET:-
However, the SONET also has some limitations too. They are provided below:-
Multicast traffic:-
Multicast traffic requires different circuits for the individual destination. Thus, a copy is
created in the both destinations. The result in the multiple copies of packets will deduct
the bandwidth in the network.
Fixed circuits:-
In the SONET, the ring nodes are placed in the point-to-point circuit. The bandwidth may
be wasted if they are not used by the SONET. Thus, this causes limitations while
transferring data & it creates bursts.
Wastage of protection bandwidth:-
We know that always 50 % of bandwidth is differentiated for security. However, the
SONET does not follow this method. This causes the vendors difficulties to select the
appropriate amount of bandwidth required for security.
PROTOCOL LAYERS in the SONET STANDARD:-
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The SONET relies on the four protocol layers entire works of multiplexing, organizing
transmitting & routing frames each of that controls each aspect of the whole transmission. These
four levels are given below.
1. Photonic Layer:-
This layer converts signals between optical & electrical form.
2. Path Layer:-
This layer is concerned with receiving the frames from source to destination & vice
versa.
3. Section layer:-
This layer generates the frames & looks after the monitoring errors in transmission.
4. Line Layer:-
This layer handles the part of synchronizing, demultiplexing & multiplexing.
OPERATION, MAINTENANCE & ADMINISTRATION:-
The SONET also represents the management of the networks in support of the administrative
functions, operations & maintenances. Overheads added in the SONET frame gives the control
of network monitoring & managements. It is known that the 4% of the actual bandwidth is
consumed by the overhead of network management.
Some of the monitoring functions are given below:-
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Failure of the system
Parity errors
Pointer loss
Frame loss
Signal loss
Synchronization loss
Operation:-
Electrical signals are converted to the optical levels by the SONET for transmission. We know
that the SONET is not very long & a single piece optical fiber. The transmission can transform
through routers, repeaters & switches along with the ways from the source to destination as well
as by more than one intermediate multiplexer to boost the signals. Transmissions among
themselves are composed up of 810 bytes frame which are sent out at the rate of 8000 Bps.
Section: It is a single length fiber optic cable.
Line: It is a segment of the any path which travels between the two multiplexers.
Path: It is the complete route between the destination multiplexer & the source
multiplexer.
WIDE AREA NETWORK:-
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WAN stands for Wide Area Network. It is a computer network which covers the multiple
distance areas which spreads over the whole world. The WAN joins the multiple smaller
networks like LAN & MAN. Internet is the world’s well-nigh popular WAN. WAN technologies
usually operate at the bottom three layers of the OSI reference model. Frame Relay, SONET,
X.25, PPP & ATM are some of the technologies often found in WAN. SONET is considered as
an international standard for high speed communication across fiber optic network which
establishes Optical Carrier (OCs) levels from 51.8 Mbps to 10 Gbps & even higher.
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OVERVIEW of WAN TECHNOLOGY:-
Concept of WAN technology is majorly discoursed in the physical layer & the data link layer of
OSI model. Various protocols are used there. Some of the services interleaved by WAN
technology are frame relay, HDLC. WAN technology operates on the layer 1 & layer 2 of OSI
model. Different authorities like the ISO & Telecommunication Industry Association (TIA)
describe the access standard of WAN technology.
The functional as well as the electrical connection are defined by the protocols in the physical
layer. Whereas encapsulation of data to unknown location is described by the protocols in the
data link layer. We know that ATMs & Frame relays are taken for frame transfers.
WAN DEVICES:-
Some of the components of the WAN technology are given as follow:-
Routers
Modems
Core Routers
Access Servers
CSU/DSU
WAN switches
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SYNCHRONIZATION:-
It is good to know what the plesiochronous, synchronous & asynchronous is before
understanding the concept & details of the SONET. Signal occurs at the same rate in
synchronous. However, the phase difference between the signals lies in their limits. Propagation
delays introduced in transmission networks creates the phase difference. Every clock is tracked
towards Primary Reference Clock (PRC) in synchronous.
When two signals comes at the same rate plesiochronous is created with variation. Thus, clocks
also may be achieved when two networks are connected from two RPCs. The differences in the
result are the plesiochronous difference. Differences in the result occur even if the clocks are
accurate.
Whereas in the asynchronous, signals does not come in the same rate. It is said to be
asynchronous when the difference between the two clocks becomes more than the
plesiochronous difference.
Some of the synchronous sources available are as follows:-
Local external timing:-
It is created by a satellite-derived clock or an atomic Cesium clock with a device in the
same central office as the network element. Along with sync-status messages placed into
the DS1 overhead supplied by the clock, the interface is often a DS1,
Holdover:-
A network element reaches a holdover mode in the absence of high quality timing as a
last resort until high quality timing is available. The network element uses own timing
circuits as a reference in this mode.
Line-derived timing:-
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Monitoring the S1 sync-status bytes to ensure quality, a network element can be
configured to derive its timing from the line-level.
SONET EQUIPMENTS:-
The traditional sections of network components are no longer distinct with advancement in the
SONET chipsets. However, as new equipment can be examined in light of the architectures it
supports the network architectures which have relatively remained constant. So, in terms of the
old sections, there is always a value in viewing newer plus traditional equipments.
Regenerators:-
Only the section overhead is terminated by the traditional regenerators. Line or path is not
affected by it. Long haul routes are extended by the generators converting optical signals already
passed a long distance of electrical format. It also retransmits a regenerated high power signal.
Regenerator has been replaced largely by optical amplifiers since late 1990s. Even the
transponders of wavelength-division multiplexing systems have absorbed some of the
functionality of regenerators.
Digital cross connect system:-
DCSs or DXCs recently often supports various high speed signals. It also allows the cross
connection of the DS-1, DS-3 plus the STS-3s & other connections from one input to other.
Again various subtending rings are supported by the advanced DCSs simultaneously.
Add-drop multiplexer:-
They are the most common network elements. Though the new generation systems often support
various architecture, the traditional ADMs were developed to operate only in one architecture.
Traditionally ADMs have a low speed side & a high speed side that contain electrical plus
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optical interfaces. It is known that the low speed signals multiplexed by the network element are
taken by the low seed side & vice versa.
SONET STANDARS:-
Telcordia GR-253-CORE, SONET Transport Systems: Common Generic Criteria
Telcordia GR-499-CORE, Transport Systems Generic Requirements (TSGR): Common
Requirements
ANSI T1.105: SONET-Basic Description including Multiplex Structure, Rates and
Formats
ANSI T1.119/ATIS PP 0900119.01.2006: SONET-Operations, Administration,
Maintenance, and Provisioning (OAM&P) - Communications
ITU-T recommendation G.707: Network Node Interface for the Synchronous Digital
Hierarchy (SDH)
ITU-T recommendation G.783: Characteristics of synchronous digital hierarchy (SDH)
equipment functional blocks
ITU-T recommendation G.803: Architecture of Transport Networks Based on the
Synchronous Digital Hierarchy (SDH)
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NEXT GENERATION of SONET:-
The requirement to transport multiple PDH signals in the network drove to the creation of the
SONET. Some of the transport multiple PDH signals are DS1, DS3, E1, E3 etc. Moreover, other
chunks of multiplexed 64 kbps pulse code modulated voice traffic are also considered as the
PDH signals. Next former application was the power to transport ATM traffic. In order to help a
huge mass of the ATM bandwidth a concatenation has been developed, where small multiplex
containers are oppositely multiplexed to create a huge container. This helps out the huge data
oriented pipes.
However, inflexibility is one of the major problem with traditional concatenation. This depends
on the data & voice traffic mix which is required to be carried. The fixed size of concatenated
containers creates a huge mass of unused bandwidth left over due to the fixed sizes of
concatenated containers. For an instance, if a fitting of 100 Mbps Fast Ethernet connection inside
a 155 Mbps STS-3c container will lead to considerable waste of the bandwidth. It is vital need
for all the intermediate network components to support newly introduced concatenation sizes.
The introduction of Virtual Concatenation has solved this problem.
Arbitrary assembly of the low order multiplexing container, creating huge containers of arbitrary
size up to 100 Mbps is done by the Virtual concatenation (VCAT). It can be done without the
specifications for intermediate network elements that support this type of concatenation. Virtual
concatenation leverages the X.86 or Generic Framing Procedure (GFP) protocols. In order to
map payloads of arbitrary bandwidth to virtually-concatenated container, multiplexing containers
based on the short term bandwidth requires the network. We know that the dynamically alter
through dynamic virtual concatenation in the bandwidth is possible by the Link Capacity
Adjustment Scheme (LCAS).
Ethernet over SONET is referred as the set of the next-generation SONET protocols which
allows Ethernet transport.
SONET HIERARCHY:-
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DEPLOYMENT of SONET:-
We know that the SONET equipment is deployed in various sectors by the service providers.
Various companies, public-service corporation, governments as well as high level clients have
adopted deploying the SONET. Nowadays SONET has become so popular among all categories
of customers. This is because the SONET has a lot of advantages like scalability, reliability, high
performance rates etc. SONET is being used in the customers’ self-governance or in a joint
central office. Their main objective is to achieve WAN connectivity.
SONET is being used for the transporting process of the ATM, Frame relay, DS-1, IP etc. to
other services. This is done by the support of hub based & ring based configuration. The most
popular SONET topology is ring based configuration. It helps in the network’s survivability.
Implementation of dual ring configuration is required to achieve further more survivability.
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SONET SIGNAL:-
The SONET technology carries signals containing various capacities across the synchronous &
flexible hierarchy that achieves the bytes provided multiplexing connive. It is also simplified
with the byte provided to it.
The first step in SONET multiplexing is to create the base signal which operates at the speed of
51.84 Mbps. It is also regarded as Synchronous Transport Signal, level 1 (STS-1). Generations of
the family of STS-N signals takes place by the occurrence of various levels. Here is the table
defining the OC as well as the synchronous signals.
THE BASIC UNIT OF TRANSMISSION IN SONET:-
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In SONET, STM-1 (Synchronous Transport Module, level 1) is the basic unit of framing. It
operates at 155.52 Mbps. We know that SONET refers to it as the STS-3c (Synchronous
Transport Signal, concatenated 3).This depends on whether the signal is carried optically or
electrically. However, its bit rate, frame size& function is same to the STM-1.
Again, it is known that the SONET offer additional basic unit of transmission. The speed of
operation is 51.84 Mbps which is the one third to STM-1, STS-3c & OC-3c carrier. This speed is
determined to bandwidth specification for PCM encoded voice in telephone signals at the rate in
which a STS-1 & OC-1 circuit carry bandwidth equal to the standard DS-3 channel. DS-3
channel carries 672.64 Kbps voice. STS-3c & OC-3c signals are composed of three multiplexed
STS-1 signal. Even STM-0 is support the SONET equivalent to the STS-1 & OC-1.
1. Framing:-
Packet oriented data transmission like Ethernet usually contain a packet frame of header & a
payload. Here at first the header is transmitted then the payload. However, in SONET this is
slightly modified. Instead of transmitting the payload first, the header is termed as the overhead
is interleaved during the transmission with it. First part of the overhead is transmitted & next the
part of payload. Again, the part of overhead then part of payload till the whole frame’s
transmission is completed.
The frame is of size 810 octets in the case of the STS-1 whereas the STM-1 & STS -3c frame is
of 2430 octets. The frame is transmitted 3 octets overhead for STS-1 with payload of 87 octets.
This process repeats for nine times till 810 octets is transmitted per 125 Mbps. 9 octets of
overhead are transmitted following 261 octets of payload in STS-3c & STM-1 that functions
thrice fast than STS-1. This process again repeats till nine time. By this time 2430 octets is
transmitted per 125 Mbps. This is represented displaying frame graphically in SONET in 90
columns & 9 rows to the STS-1 & 270 columns & 9 rows to the STM-1 & STS-3c. Thus,
overhead as contiguous block like payload in this representation.
We use STS-1 & 270 columns interchangeably in practice. However, the OC designations refer
to signals in optical form. Thus, it is inaccurate to say that OC-3 consists three layers. But we can
say that it consist three STS-1s.
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2. SDH frame:-
The first 9 columns are the overhead & the pointers in STM-1 frame. For simplicity, frame here
is shown rectangular with 270 columns & 9 rows. However, the bytes are not transmitted in this
order by the protocol.
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We know that STM-1 frame transmits in 125 Mbps. So, on a fiber optic circuit of 155.52 Mbps
OC-3, there are about 8,000 frames. This frame contains pointers, overhead & Information
Payload (IP). Administrative Unit Pointers (AUP) & Section Overhead (SO) is made up of the
first 9 columns of the frame. The remaining 261 columns makes Information Payload. Within the
information payload, Administration Units (AU) are identified by the pointers (H1, H2, H3
bytes). Hence, after accounting for the overhead, OC-3 circuit carries 150.336 Mbps of payload.
Administrative Units are carried within information payload, with their own frame structures
consisting 261 columns & 9 rows recognized by pointers. There are more than one virtual
containers (VC) within the Administrative Units too which consists of VC payload & path
overhead. We know that path overhead is at the first column which is followed by the payload
container. The pointer indicates the row four where the Administrative Units contain their phase
alignment inside STM frame.
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Now the section overhead is divided into two groups. They are Regenerator Section Overhead
(RSOH) & Multiplex Section Overhead (MSOH). Te information gained by the overhead from
transmission system is then utilized for a broad range of the management function. This can be
for service channels, detecting failures data communication monitoring transmission quality etc.
Byte-by-byte & row-by-row is a serial fashion how the STM is transmitted in a continuous way.
3. Transport overhead:-
For measuring & signaling transmission error rates the transport overhead is used. It is composed
in the following way:-
Section overhead:-
It is called Regenerator Section Overhead (RSOH) in SONET terminology. Here, there
are 27 octets which consist of information related to frame structure that is needed along
the end equipment.
Line overhead:-
It is called Multiplex Section Overhead (MSOH) in SONET terminology. Here, there are
45 octets which consist of information related to the Automatic Protection Switching
messages like maintenance messages, alarms & error correction as they may be needed
along networks.
AU Pointer:-
It points towards location of first byte in the virtual container i.e. J1 byte in the payload.
4. Path virtual envelope:-
Path data is the data transmitted from end to end. It is broken down into two parts:-
Payload overhead (POH):-
Payload overhead employs 9 octets for end-to-end error measurement & signaling.
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Payload:-
STS-1 payload carries a complete PDH DS3 frames. Path overhead is added when the DS3
enters a SONET network. The SONET network element entering the SONET network is the path
terminator or the generator. If the path or the line ended then the section is terminated too. It is
known that the line or the path is terminated by the SONET regenerators.
To form other degree of the SONET hierarchy, three STS-1 signals are multiplexed. This signal
multiplexed by the interleaving bytes of 3 STS-1 frame forms STS-3 frames which consists
2,430 bytes that transmits in 125 Mbps.
We know that Dense Wave Division Multiplexing (DWDM) are the circuits which are used as
the basis to long haul circuits & all modern submarine communication cable systems.
COST:-
However, the SONET technology is costly. It provides its services at about 20% higer than the
other services in the market. Again, the prediction of the SONET technology’s world market is
increasingly 17.4 % every year. This has proved that the SONET technology is going to rule the
entire world in the near future.
CONCLUSION:-
We have now come to know that the SONET has specialized various standards needed to insure
data communication & efficiency. This has supported a lot to the customers in the standard
communication. Applications like teleconferencing, HDTV etc. has been created with the
combination of the telephone & data communication. These need a high mass of bandwidth. It is
known that it is only SONET that provides the large amount of bandwidth. SONET has a speed
of 10 Gbps for the data communication & voice traffic. This is why all the vendors have realized
the importance of the SONET technology.
31. SONET
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Now we have been cleared that the SONET is the only technology which is most efficient to
every users in the whole world.
ACKNOWLEDGEMENT:-
I have worked hard to make this project a reliable & appreciable to everyone. I have gone
through the various curriculums, deeply on SONET to make my project much worthy. During
this course I have gone through many related websites links & done a deep research related to
SONET.
My special thanks goes to Lecturer Mr. Ayush Mani Subedi. He has played a vital role by
assisting me in collecting & suggesting me to include all the fundamental features & functions
regarding SONET. Moreover, I would like to express my best gratitude to my colleagues Hem
Lal Thapa, Pemba Sherpa & Anjan Lal Shrestha who assisted me technically & morally
throughout my project.
