Notes on Google/Coursera IT Certificate – Bits and Bytes of Computer Networking – Week 1

Bits and Bytes of Computer Networking!


Week 1 – Intro to Computer Networking


Protocols – TCP/IP 5 layer model vs. OSI 7 layer model.
TCP/IP 5 layer Model – Physical Layer, Data Link Layer , Network Layer – delivers data between nodes (IP), Transport Layer – sorts out who gets that data, (TCP), Application Layer (payload)
Basics of Networking Devices:
-Cables:
-Hubs & Switches:
-Routers:
-Servers & clients:

My response to another user on the forum:

You are correct more or less except you need to realize that “Ethernet” aka LAN is not “Internet” aka WAN and they are sectioned off by different types of routers. Theres a lot going on here. To communicate a request from two different internet servers all you need is the IP, the mac address is the concern of the routers that each server is individually connected to on the back end. The routers perform the IP to mac conversion locally, and the internet transmission uses DNS to resolve to named domain.com to an IP address, which is then carried around by routers until it reaches the LAST router, which then does the final IP to MAC address conversion.

When a request goes out to a domain name, what is really going out is a DNS resolve request, to resolve a name to an IP. This will go through a chain of DNS and nameservers and return the IP of the server in question. At this point a 2nd conversion will happen from IP to Mac address, and that will all happen more or less in the background, taken care of by a series of Routers along way.

  • We later learned that, in more advanced lessons in the course.

 

Great customer service requires

  1. 1) exhibiting empathy,
  2. 2) being conscious of your tone,
  3. 3) acknowledging the person you’re talking to and
  4. 4) developing trust with the user.

Leave a Reply