Friday, August 15, 2014

Wireless Networking challenges

I must say Data (Voice+packet) that can be carried per Hz (Unit for Frequency) rapidly gone up in this decade. Thanks to intelligent brains in finding better results in Signal processing and Mobile communication. I am sure we will witness much faster mobile communication and intelligent nodes (Your AC, Smoke detectors, Window, lighting etc) in coming days. Wireless networking is definitely a happening field in networking sector. Wireless radios have matured from  proprietary technologies to heavily into standard based solution in a very short span of time.

Primary challenges in front of wireless networking startups,

Improve SNR - Signal to Noise ration

  1. Increase Signal penetration (Gigantic Base Station to Pico cells). LOS (Line of Sight) performance in Non-LOS conditions is the goal.
  2. Intelligence to Antenna (Reducing transmission loss, noise cancellation and coverage improvement)
  3. Beat Shannon's law

From service providers point of view:

  1. Mobility - Signal handoff, LTE advanced and WiMax advanced made a breakthrough here.
  2. Wireless device management - Software Defined radio
  3. Monitoring - Intelligent Load sharing
There may be numerous other challenges but above list offers a simple baseline.

Interesting part of this post is to cover wireless networking startups but wait for my next post to know about Kum networks, DIDO

Debugging with GDB - Lets decypher Segmentation Fault

I want to be a philanthropist. Hold on!  Are you looking for any link to get money? Get out of my website if you have wrongly landed here in search of money. I am sure Google (Search engine is not the key word any more) does a good job in listing search results. 

I only offer information in netglutton, after all information is wealth. I recently gathered more information about a tool i use almost every day in my Software Engineer role. a magic three letter tool "GDB - GNU Debugging".

Process crash or Core singles out as "Critical" defect among tons of defects in any software system. It is so severe that both test engineer and developer have hard time in resolving process crash. As a software test engineer i have encountered 100s of Process Crash scenarios. 

Why it happens?
Simply, unhandled exception. Yes, Process crash happens due to unhandled exceptions like Null Pointer, Memory error, EOF etc in code. As a test engineer i have not only seen simple way to trigger a crash but also a most difficult ones. 

If you have root access, find a non-restartable process (ps -ef) and do "kill -9 or -11".

"Breaking Point" is very critical issues in code. I really dont want to get into the reason for Crash/Cores. A C/C++ developer must know about GNU Debugging (GDB). Software test engineer should also know about collecting core file, attaching to GDB and finding BT (BackTrace short form).

Unhandled exception OR Null pointer OR Segmentation Fault in process leads to process restart. Process failure leads to core file. Back trace using GDB helps to find breaking function call /memory location/ value. 

With above contextual information, go through following help links for more information about How to GDB?