16 Most Common Questions Of Cisco SFP-10G-SR You Need To Know

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16 Most Common Questions Of Cisco SFP-10G-SR You
Need To Know Communication has been there since
the beginning of human race. With the evolution
of humans, the technology for communication also
evolved. Social networks are becoming essential
in human lives. More advancement is coming up in
the communication sector. The speed of
transmission is increasing exponentially. Mbps
speeds have given way for Gbps speeds. Wireless
communication is gaining popularity. The
telecommunications network is quickly heading for
a 10G fiber network. Actually, it has gone
beyond 10G. People are widely using 10G switches.
Cisco is the most popular in the market. If you
choose a Cisco switch, you will have to use Cisco
compatible modules. Here we will discuss some of
the most common questions regarding the Cisco
SFP 10G SR module. The contents were mostly
inspired from Cisco, Amazon and Quora
websites. 1. How Cisco SFPSR differ from Other
Cisco 10G Optical Modules? Different models
have different transmission distance and other
specifications. The same SFP SR module has
different variations in itself. The distance
ranges from 300m to 80km. You can refer the
Cisco website for a detailed comparison of
features. As transmission distance increases so
do the price of the module. Most of the short
distance models use Multi mode Fiber(MMF), while
the lo ng distance ones use Single Mode Fiber
(SMF). Most of them can withstand a temperature
as cold as 0 ?.
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• What's the distinction between SFP SR and LR
  models?
• The "SR" denotes "short range", which supports a
  shortwave (850nm wavelength) multimode fiber
  (MMF). This can transmit for distances ranging
  from 2m to 300m. This design has the advantages
  of low cost, smallest fiber module, and less
  power consumption.
• "LR" stands for "Long Range", which supports
  single-mode fiber (SMF) of long wave (1310nm).
  The distance can range from 2 km to 10 km or even
  25 km. This configuration is characterized by
  long distance, increased prices and more power
  consumption.
• What's the difference between SR and SR-S models?
• SR S makes use of S class optics. According to
  Cisco, these are designed to serve ente rprise
  and data center 40G and 10G. You may think that
  the S class will cost more. But it is actually
  the opposite. By avoiding unwanted features,
  S-class is actually cheaper than non-S-class.
• Apart from this, S-class supports Ethernet only.
  It is not compatible with Optical transport
  networks. Moreover, S-class and non-S-class
  optics operate in different temperature ranges.
  Thus, if you dont need any special features like
  extra tolerance for temperature, S -Class optics
  can save you a considerable amount of money.
• What are the main distinctions between SFP-10G-SR
  and SFP-10G-T?
• Both of them are hot-pluggable with a calculated
  soft-start. They are interoperable with any SFP
  connector system and cage. On the other hand,
  they have entirely different perfor mance when
  it comes to the 10G switches. The T module uses
  the Cat6a cables for a 30 m link length and not
  RJ45 cables. Whereas, SR operates with OM3 cables
  and uses LC connectors. They have a link length
  of 300m and above.
• These transceivers are much cheaper as compared
  to the lately released 10G copper module.
• Compare SFP-10G-SR and SFP-10G-LRM

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• How does ER differ from SR?
• ER expands to Extended Reach. These modules can
  achieve transmission distances of up to 40km
  over single-mode fiber. ER uses 1550nm lasers and
  is cross-compatible.
• SR is short for Short Range these transceivers
  support link length of 300m and use 850nm
  lasers. Unlike ER, they are transmitted over
  multimode fiber.
• How do ZR and SR differ?
• ZR is also a variation of Extended Reach. Unlike
  ER, they can transmit 10G data rate around 80km
  distance. Actually, this format is unofficial,
  that is not technically an IEEE approved
  standard for networking hardware.
• SR is short for Short Range these transceivers
  support link length of 300 m and use 850nm
  lasers. Unlike ZR, they are transmitted over
  multimode fiber.
• What is the specialty of SFP-10G-T-S as compared
  to 10G-SR?
• SFP-10G-T-S has the same parameters with
  SFP-10G-T except that they use copper modules.
  The T S modules use RJ45 connectors.
• SFP SR operates over OM3 cables with a distance
  of 300m over LC connectors.
• What does -X in LR-X and SR-X means?

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usually RJ45 cables. High-speed cables include
direct attach and active optical cables. The
following picture shows these
The choice of patch cable depends on the nature
of the transceiver and connector. If LC
connectors should be used, the LC to LC patch
cables is to be used. This will be the ideal
choice for a Cisco SFP 10G SR transceiver. 13.
Differentiate among single-mode and multimode
fiber? In optic communication, single-mode fiber
(SMF) is for the transmission of remote signals
over long distances. Light in the single-mode
fiber is along the straight line with minimum
possible spreading and reflection. So its
propagation distance is very far and can transmit
over long distances with little attenuation.
They can transmit up to 80 km. Multimode fiber
(MMF) carries multiple light rays. They follow
the principle of Total Internal Reflection and
are usually used for short distances. They can
attain a maximum distance of 2 km.
The core diameter is in the range of (8-10)/125µm
for SMF so as to minimize the spreading of rays.
MMF uses a wider diameter in the range of
50/125µm,62.5/125µm. LASER is used as the light
source in case of SMF. But for MMF, LED is the
preferred light source. SMF uses a higher
bandwidth of 2000 MHz/km while in the case of MMF
it is only 50 -500 MHz/km.
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For SMF, the sheath color is yellow. In the case
of MMF, it is orange or aqua green. As
discussed in the first point, SMF has very low
levels of dispersion as compared to MMF. The
differences can be summarised as follows
Category SMF MMF
Transmission Distance gt5km 2km (100M),1Km(1G/s),550m(10G/s)
Core Diameter (8-10)/125µm 50/125µm,62.5/125µm
Light Source Laser light source LED light source
Bandwidth 2000MHz/Km 50MHz500MHz/Km
Fiber Wavelength 1310nm,1550nm 850nm,1310nm
Sheath Colour Yellow Orange or Aqua green
Modal Dispersion Low dispersion High dispersion

• Can we use Cisco SFP Transceivers in Other
  Brands Equipment?
• In the case of cost sensitive users, they hope
  that they can buy one module and can use it in
  different brands equipment. So the question
  arises as to whether we really can use a
  different transceiver than the Original intended
  one. The answer is negative in most cases.
• Different models of transceivers will have their
  own special encryption. Runtime verification is
  done when you insert a different module. If the
  verification fails, the system shuts down. So it
  is always safe to use the prescribed equipment
  only.
• However, there are many third-party modules,
  which are compatible with Cisco equipment.
  Cozlink is one of the main players. Normally, the
  price of such modules will be less than the
  original one. If you are too concerned about cost
  and willing to com promise on quality, you can
  go for third party modules.
• Basic precautions to install and remove 10G SFP
  SR modules
• Refer to the following video for instructions on
  how to install and remove 10G SFPSR modules

https//www.youtube.com/watch?vBulkCbMfpe4
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The basic precautions are listed below
1) Installing the module

• Though data rates may be same, one module may not
  be suited for a particular slot. So insert an
  SFP module preferably into an SFP slot only.
• Carefully check the compatibilities of each
  module before connecting it to any s lot. If
  incompatible modules are inserted without
  caution, a system break down may happen. This can
  lead to monetary losses as well.
• Check the network configuration connect the
  modules that are best for the current
  configuration of the network.
• Always clean the modules before installing, be it
  an SFP module or SFP module. This will prevent
  contamination in the system.
• Do not expose your eyes to fiber optic equipment.
  They emit laser and infrared rays that may be
  harmful to you. If at all, you need to examine
  something, make sure that the light source is
  disconnected.
• You can damage the electrostatic discharge, if
  not careful. In order to prevent it, always wear
  an antistatic wrist strap while handling the
  network equipment.
• 2) Removing the optical module
• It is not good to frequently pull out or insert
  the SFP module. This can badly affect the
  lifetime of the module.
• If you need to remove the optical module, please
  pull out the rod first. Then, through the rod
  remove the optical module.

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• Loss of Product packets
• Some of the possible reasons
• The device may not match with the electronic
  function of the optical module. A mismatch can
  arise between master chip and the device.
• Failure of Physical line or equipment may cause
  problems. Error may seep into Routing
  information
• Optical port contamination
• The optical links can become unstable if the
  optical interface contamination rises above some
  safety limits. Several reasons can be attributed
  for this. Some of them are
• Over exposure to the environment may cause dust
  particles to enter and contaminate the port.
• If a contaminated connector is used, this can
  lead to a secondary contamination in the optical
  ports.
• If connectors have major scratches, this can
  cause harm to the optical ports.
• The quality of fiber optic connectors should be
  taken care of. If low-quality connectors are
  used, the optical ports and modules can get
  contaminated fast.