Short details about Submarine optical fiber cables

1. SUBMARINE CABLE
Deep on the ocean floor we find communication cables
made to carry signals from one land to another. The first
undersea communications cables, laid in the 1850s, carried
telegraphy. Now these cables carry our phone and internet
traffic. Yet, they remain relatively hidden in the depths of
the ocean.

2. LAYER’S OF OPTICAL FIBER
1) Polyethylene
2) Mylar tape
3) Stranded steel wires
4) Aluminum water barrier
5) Polycarbonate
6) Copper or aluminum tube
7) Petroleum jelly
8) Optical fibers
It has basically 8 layer:-

3. SUBMARINE CABLE MAP
IN INDIA
https://www.submarinecablemap.com

4. INSTALLATION PROCESS
https://youtu.be/XQVzU_YQ3IQ

5. HOW MAINTENANCE I S DONE
https://youtu.be/FtEw19JX-UE

6. WORKING
Light travels down a fiber-optic cable by bouncing
repeatedly off the walls. Each tiny photon (particle
of light) bounces down the pipe like a bobsleigh
going down an ice run. Now you might expect a
beam of light, traveling in a clear glass pipe,
simply to leak out of the edges. But if light hits
glass at a really shallow angle (less than 42
degrees), it reflects back in again—as though the
glass were really a mirror. This phenomenon is
called total internal reflection. It's one of the
things that keeps light inside the pipe.

7. OVERCOMING THE CHALLENGES
Accident-Prone Environment:-
Submarine cables are engineered to sustain around 25-years of shelf life, however they are often retired
earlier than that when they start to become economically obsolete. Over that long period of time, the
environment takes its toll on the cable. Shifting tides, erosions, storms, and saltwater intrusion are all
potential disruptors of data flow. As a matter of fact, around 6% of cables are damaged through abrasion as
the current scrapes cables against rocky surfaces. These damages coming from the environment often cause a
variety of issues, starting from minor outages and lowered speeds to a complete loss of connectivity.
Anchor Dragging and Fishing Activity:-
Not surprisingly, the larger and more significant physical threats are man-made, coming from accidents due
to fishing vessels and dragged anchors. This type of accidental damage make-up about 60% or two-thirds of
all submarine cable faults, TeleGeography reported. This accident occurs when fishing boats and large ships
are dragging their anchors outside the designated anchoring areas, thus hitting subsea cables. Recent fault
records have indicated that merchant ships sometimes forget to fasten their anchors securely when travelling
during short passages.

8. Threats from Shark Bites:-
Cable faults due to shark bites are exceedingly rare, and it is perhaps the biggest myth
cited in the press. While it is true that in the past, some curious fish and sharks have bitten
a few cables and caused damage, they are not a major threat. Both barracuda and sharks
have been found to cause cable failure in the past, as reported by the 2009 UN
Environmental Program report. Their bites tend to penetrate the cable insulation, thus
allowing seawater to compromise the power conductor.
Damages by Extreme Seismic & Weather Events:-
Natural disasters – such as mudslides, typhoons, tsunamis, and earthquakes – are also
major threats to undersea fiber. In Asia’s underwater network, a large number of cables is
concentrated in the middle of a major seismic belt, which resulted in many catastrophes in
the past where natural disasters severed about half of the pre-existing trans-pacific cables.
Quake-damaged undersea cables are, unfortunately, quite common, especially in
earthquake-prone zones around Japan and Taiwan. When submarine cables are severed
following a major earthquake or other natural disaster, it can cause disruptions in internet
access and communications traffic that could cost both money and time.

9. SOLUTION?
To overcome damages to undersea cables, the subsea networks developed over the past 5
years were designed with enhanced physical security in mind. In order to protect the fiber-
optic cable from water environmental hazards, the undersea cables are typically wrapped in
multiple layers of protective coating. To further increase its protective property, the cable is
encased in a protective pipe that extends for several miles from the shoreline. In some cases,
operators may use automated technologies that are placed inside the cable housing’s
repeaters. This technique can help to avoid the cost and time of pulling the damaged cable
out of the sea to fix it, only to redeploy it underwater
To deal with extreme seismic and weather events, the Southeast Asia-Japan Cable (SJC)
consortium designed an underwater fiber cable deployment path that intentionally avoids the
earthquake-prone zone in North Asia. Similarly, the route of NTT Communications
Corporation’s (Tokyo) Asian Submarine-cable Express (ASE) has taken a similar approach.
Their new line is designed to go around the damage zone, rather than taking the shortest,
straightest line from both ends. This model is intended to bypass high-risk zones and avoid
the damage caused by both earthquakes and typhoons.

10. Submarine Cables to/from India

11. Lists of Under Sea Optical Fiber in India
Currently, there are 15 subsea cables (17 if Seacom and MENA are considered seperate cables) landing in 15 cable landing
stations in 5 cities across India, in Mumbai, Chennai, Cochin, Tuticorin and Trivandrum.
BSNL plans to construct new cable landing stations in Digha, Cochin, and the Andaman & Nicobar Islands. IOX will construct a new
cable landing station at Puducherry. Reliance Jio is planning for new cables and landing station.
1) Tata Communications owns five cable landing stations, three in Mumbai, and each in Chennai and Cochin.
2) Global Cloud eXchange (formerly Reliance Globalcom) owns the Versova Cable Landing Station in Mumbai for FALCON,
and Trivandrum cable landing station for WARF cable connecting Maldives and Sri Lanka to India.
3) Reliance Jio owns BBG cable landing station in Chennai and AAE-1 cable landing station at Versova beach in Mumbai
4) Bharti Airtel owns three cables landing stations, two in Chennai and one in Mumbai.
5) Sify Technologies owns cable landing station in Mumbai for MENA and GBI submarine cable systems.
6) BSNL owns its first international submarine cable connecting India and Sri Lanka (BLCS) and its cable landing station in
Tuticorin. The Digha Cable Landing Station in West Bengal is newly approved in May 2011 by the department of
telecommunication (DoT) of India for a submarine cable project between India and South-east Asia. BNSL is expected to own
the Digha Cable Landing Station. BSNL has awarded NEC to build the Chennai- Andaman & Nicobar Islands (A&N Islands)
submarine cable system, and will construct a new cable landing station in Chennai and several stations in the Andaman &
Nicobar Islands.
7) Vodafone owns BBG cable landing station in Mumbai.
8) IOX plans to construct a new cable landing station at Puducherry for its IOX cable.