This is
not a technical blog, but an experience with a BSNL call center agent (she sounded like my fisherwoman) for
help. On the call I had to help her – me being a network engineer for more than 10
years now – got me to type this for educational purposes only. And please don’t make me comment about the language gap on the call.




          So here
goes a blog which you can bookmark – this is my way of giving back to the world
– you can tag it as, hashtag educational and forward to your friends. In this blog the network which is being referred to is the data part and not you voice call network.


          Troubleshooting cellphone network issues are easy,you just refresh your Facebook or Google page and if there’s no
network you will not get to your familiar page. Please don’t ask me about Jio’s
VoLTE setup because this blog is not about that. By the way, an expert in that
field says it’s all about marketing!



        Let’s start, in the beginning there was Adam and Eve – no scratch that – there was Alexander Graham Bell’s invention; the phone. A cable (two wires) connected directly into the landline handset. Physically speaking, the wire from BSNL with its RJ11 plastic connector entered the phone and you heard the dial-tone. Yes, we tend to forget that there was something called as a dial-tone. Then came the
high frequency sound emitting modem that used to wake all the neighbourhood when it connected to the internet at night. The modem sat between the phone and split the data and voice. Voice exited the modem via another RJ11 cable and entered the
cordless handset at the other end of the wire. (Notice how the landline
handset has been upgraded to a cordless one.) The modem gave an RJ45 cable handoff to your computer for data connectivity. The bigger RJ11s are called RJ45s (Singular
RJ11/RJ45, plural RJ11s/RJ45s).


         To make
this even more interesting, we will consider that there are two Wi-fi routers that are connected
back to back so as to cover a wider/larger area (like the penthouse you live in).
The modem is nowadays replaced by an ADSL router. ADSL is a feature which is required on BSNL routers so as to convert the two-wired connection into an 8-wired one. The second router which is connected in series to the first router by a LAN cable. The second router can be of a cheaper make, because ADSL features aren’t required on it (since the input is already 8-wired) – so simple, right!. But, now the problem arises; the cellphone connectivity via
Wi-Fi keeps fluctuating as soon as the latter router/modem is brought into the
network. The two PCs connected on both the routers in different rooms of your penthouse are facing the same problem.

           Troubleshooting
this needs two PCs – one connected to one router on the lower level and one connected to the terrace router of your penthouse. However, due to 
this educational blog you can skip the need for two PCs. Hehe. So lets turn on your singular Windows machine, and no, cellphones don’t make the cut
because the apps are not standardized. Also, let’s take one small step for mankind
first, by following some basic steps.

  • On the Windows PC, get to the run window (Windows+R).
  • Type cmd. Hit enter. (cmd means Command in
    short).
  • A black command prompt window will appear.
  • Type in ‘ipconfig’. This will bring up the IP
    address your PC has acquired.
         So if the
router is disconnected from the PC, it will not have an IP address. Similar to
no Wi-Fi on your cellphone or a red cross on the small computer icon at the
right hand side bottom corner of the desktop screen (next to the time and
date). We can safely say; the router is off or conked off.



         If the
cross mark is not present on the desktop network icon or the familiar hand-fan
symbol on the cellphone can be seen, the devices will have an IP address. So
the prior command can be kept on firing repeatedly (use the up arrow key and hit enter) and lookout for an IP address, it would look like this 192.168.0.2, ninety-nine percent
of the time. If you are connected via a router (this is standardized). Then there
is the 169.254.x.x, which is reserved by Microsoft to show that there’s no
network. In networks, everything is as per IEEE standard, and yes, IP addresses
is how you trace the cyber-attack is from North Korea or not. IP addresses are inventoried by a global body.




            So
169.254.x.x and no IP address portrays the issue lies in the router at your
premises. Don’t call BSNL for help unless it’s on lease from them. And before they
send a replacement (or you decide to run out and buy a new one) check the
cables. Yes swap the RJ45 cables with a friend’s working one, and this step cannot
be missed, so as to prove to BSNL that it’s the router’s fault and solely the
router’s fault.


             Next we
come to the part where the hand-fan symbol on the cellphone is accompanied by
an exclamation, which is similar to the one encompassed in a yellow triangle on the
network icon on the screen of the desktop PC. This means, there’s no internet,
yet. After waiting for an eon you may tend to realize that the exclamation sums
up your life. Don’t worry!

  • in the command prompt black window; Type ping 192.168.0.1 -t (that’s ping<space><IP
    address of the router><space><minus>t)
       So what’s
the router IP addres? The “ipconfig” command fired would display a lot of information
and now we have only covered the IPv4 (version 4) part of it, don’t worry there’s
only one more piece of information required from the “ipconfig” output; the
default gateway. The IP address dotted after the words “Default Gateway” is the
IP address of the router. The next hop for your data packet.
  • Hit Ctrl+C
    to stop the ping.

         So
pinging the default gateway, yes ping is a technical word and yes it does the
same thing; says hi to the router. Wait for the output to stabilize after
hitting “Ctrl” and “C” together and read the third-last line, or anywhere where
it says, “Loss is equal to some value or percentage loss is some value.” 



         Hit the
up arrow and run the ping again for live replies to the ‘Hi’ sent from the PC to the
router. 100% loss is an issue, and less than 7% loss is acceptable. But zero is
the figure we are looking for. Else the cables are loosely connected or gone bad. And
since the PC had received the IP address from the router, the router/modem is
not to be blamed. The medium via which we get to the router is the problem (for
Wi-Fi distance matters.) 




           Did you
guess the solution to the penthouse problem? The fluctuating Wi-Fi, the two
routers are providing two different IP addresses and which router is the
default gateway? Confused, so are all the devices in this network. The solution
being DHCP; login into your router (every manufacturer will have standard way
of doing this) and disable DHCP from one of the routers. DHCP in which the “P”
stands for protocol – yes a synonym for standard – and this Dynamic Host
Configuration Protocol feature provides IP addresses to new devices connecting
to any network. Now the BSNL call centers will wonder how everyone knows about
disabling DHCP (wink). Common sense says don’t disable DHCP on both the routers
else each new device will have to be provided an IP address manually, unless you
want it that way. Why? For security reasons where all IP addresses are
inventoried, see you are now a Security expert too, or maybe you are getting
there. Wait,
we are not yet done with the exclamation mark! The internet is still not
accessible! Oh! The exclamation mark!
  • Type
    ping 4.2.2.2 (where 4.2.2.2 is the IP address of a random server/website on the internet)
           Like I said
before, it can be traced whether you are the cyber-attacker from North Korea or not (but that’s
not possible else you wouldn’t be reading this blog then, right?) Look at the
replies from the website. The command ‘ping www.google.com
also works. 

         And now
we know whom to catch and for what fault. If you are in a corporate environment
the last step of pinging a website may not work as there would be a firewall
device blocking or maybe your corporation uses a proxy server or both. That’s too
much technical jargon for this blog, hence ending it. Thus pinging different IP
addresses right from the routers’ IP at your premises to the ones in North Korea,
we can determine where in lies the problem.

         “A mere
process of elimination, Dr. Watson”, that’s what Sherlock Holmes would say.   
                                                                                                          
=-=-=THE END -=-=-=

Genre: Educational

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