Basic Network Troubleshooting

         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

The Bus Driver

Length of blog: 1600 words.
Genre: Educational

*NOTE: NO PHOTOS ARE PRESENT IN THIS BLOG; ALL PICTURES ARE ADVERTISEMENTS. EXCEPT, THE ABOVE PHOTO

Sean was the burly kind. He always had a dream of driving a 16 wheeler truck, but just like any average middle class person, he wasn’t able to afford one. To fulfill his dream he purchased a small tempo on monthly installments – one day he would build on this, and achieve his goal of owning his own 16-wheeler. He couldn’t give up his day job as he had to pay the EMIs, and on his week offs he did try driving and learning his new vehicle. He realized that as he was not a permanent driver he was referred less for business offers.

A month into driving he did not have to consciously remember the three paddles at his legs. Leftwards like how the Urdu alphabet is written, but in English - A-B-C; Accelerator, Brake and Clutch. Clutch paddle being used most often, while the other leg alternating between A and B, because no one would want to break and accelerate at the same time. Slowly but steadily his confidence grew on his driving skills, but his business opportunities did not.

To avoid the crowded buses which could not handle the load of the rush hour, Sean sometimes drove to work in his tempo. Then it hit him; he added benches at the back of his tempo so as to accommodate eight people. And now he had a self-driving vehicle – at least monetary wise – the thankful passengers kept his gas tank full. He too felt he was doing a good deed for his city folk. Especially the ones who travelled far off like him across the hills which separated his work from home. He sometimes did two trips to rope in more profits.

 One such evening he turned his tempo towards home the second time. It was nearing midnight by the time he had freshened up and started back for home. And he guessed correctly that he would not get any passengers at this hour. He took the home bound journey alone. Halfway home, in slow moving traffic caused by the 16-wheeler trucks climbing the hill, his vehicle shutdown. He had lost focus and pressed the accelerator a little too late which led his vehicle to come to an abrupt halt. He turned the key in the ignition but alas it was dead. He turned on the parking blinkers, so that the vehicles behind him who too were in slow motion knew he had car trouble. His battery had dimmed out. A few blaring horns and the traffic behind him started diverting – some left, some right. A trailer driver did not realize Sean’s predicament and came too close to Sean’s tempo’s bumper and couldn’t veer left nor right causing more confusion and agony to the highway truckers. A few cars passed by, but no one helped Sean, some glared at him – one even asked him for a match box to light his cigarette, but before Sean could search it in his glove compartment and give it to him, the rest of the vehicles coaxed the cigarette wielding driver to move on with their incessant horns. He looked up and down the dimly lit road packed with vehicles – was there a breakdown van nearby. He looked at his gear box, he usually got out of this situation by giving the car a push. A push-to-start is when the vehicle is put in gear and when the pushed-vehicle reaches a certain speed you release the clutch and accelerate a little bit and the engine would catch on.

             “That’s what the clutch paddle does, it helps the engine to release and clutch the gear shaft”, Sean could remember his driving teacher’s voice in his head.

But here Sean found himself on an upward slope and no one to help him to push his car, no passengers too. He pulled on the handbrake so that he could free his legs off the ‘B’ for brake. He got out of his tempo and ran towards the trailer near the tail-end of his tempo. The trailer driver was making actions towards Sean and his mouth moved too, but all was lost in the din of the traffic and the various moving headlights. Sean tried to explain his difficulty to the driver who was not interested, but already ready to reverse. Sean saw the cleaner of vehicle jump out from the door on the other side. Sean ran to the other side of the vehicle to catch the cleaner-guy and ask him for his help to push the tempo. He too paid no heed and ran to the back of his trailer to aid his driver-master in reversing their huge vehicle.

Sean re-entered his tempo and solemnly saw the vehicles split behind him, glare at him questioningly, and pass by. He wondered if rolling backwards and making a U-turn and then letting his tempo roll head-on towards oncoming traffic would be wise. A concrete divider restricted him from going to the other side of the road. He phoned his mechanic.

                “Will my tempo gear-start in reverse?” Sean said. “My car battery died”

                “Yes, of course”, the mechanic replied, “Why what happened?”

                “I am on the second hill home, on the upwards slope and trailers all around me”, Sean shouted over the sound of the traffic

                “Yes it will, but do be careful when you apply the accelerator in reverse, the vehicle may lunge backwards – the reverse gear being the most powerful gear – be very subtle”, the mechanic said.

 Sean was delighted that all hope was not lost. Just a few minutes ago, before he had called his mechanic, Sean had seen himself spending the rest of the night right there until help arrived in the form of cops or a breakdown van. He had made peace with his situation and had smiled to himself on how he could blast music and have a small meal – beers included – in the middle of traffic and no one would or could do anything about it. He had corrected himself, they could help but who would risk their lives. Many a driver would have faced this problem themselves and would empathize with him but that did not warrant what worked for them would work for him. He had even contemplated calling his insurance company at the risk of a huge fee.

But now Sean had a plan, he got out of his tempo. He wanted a car’s length of distance between the tail-end of his tempo and the next car behind him, then he could try his reverse-gear-rolling-backwards-downhill-gear-start. But in this dark shifting traffic how would he get the space? The lane to his tempo’s right was lined with trailer’s, about half a car’s distance behind him vehicles veered left slowly to avoid his breakdown lights. He waited – a car went left and behind it was the state transport owned bus. He ran towards the left–veering bus driver with his hand raised - palm facing the bus driver - then ran towards his own tempo. He knew the driver would oblige in spite of the innumerable things that would go on in any driver’s head. But this was a bus driver, just like he was - a tempo driver with benches.

Without looking back Sean could feel the bus driver’s actions. Firstly the bus driver would wonder what the issue was. Why would someone run towards his bus in the middle of tedious traffic? The bus driver would then peer from the height of his seat over the tempo to look out for an accident, “Or was it the tempo that had caused an accident?”

               “Were there people who needed to be transferred into the bus?”

               "Was there a landslide or had the road caved in?"

                “Was this a hold-up?” Sean’s mind raced at the many reasons on why any driver would not wait.

 Yes, this bus driver was with whom Sean felt a knowing fellowship - he too drove people from point A to point B - Sean saw in his rear-view mirror that the bus driver had veered left and halted to block off a chunk of traffic. This was it. Sean released the handbrake. His tempo started to roll backwards down the slope. The gear set in reverse, he waited for the gear shaft  to gain speed and then he would have to release the clutch. He took his leg off the clutch paddle in one motion.
           
            "Not in a gradual fashion", he reminded himself. Sean was talking to himself aloud to focus.

The gear shaft locked onto the engine shaft and with a jerk the engine grunted. He then simultaneously pressed the brake and the accelerator to invigorate and ascertain the engine wouldn’t die on him yet remain where he was - there, he had used the break and accelerator together. The engine roared to life. Sean then pulled the handbrake to steady his nerves. Sean looked out front and saw he had reversed almost to the end of the angled bus and was inches from the trailers on the right. He could feel the eyes of a few passengers see his antics in the dark interiors of the bus.

Sean gave a thumbs up to the bus driver and continued forward his journey home. Oh yes! The reliable bus drivers!

--- THE END ---