Week 4 - TCP/IP Routing

TCP/IP is a series of protocols used to transmit data over the internet. What is a protocol you ask? Well, a protocol is a set of rules that computers use to talk to each other. This communication happens on the Transmission Control Protocol (TCP) and Internet Protocol (IP). TCP prepares data by breaking it down into packets, and IP makes sure these packets get sent and delivered from one computer to another.

IPv4 vs IPv6

When data packets arrive at the router, the router needs to know where the data came from and where to send the data. This is what the IP address is for. An IP address is a 32-bit label that is unique to that device, so in transmitting data, there is a source IP and a destination IP. Internet Protocol version 4 (IPv4) is the 32-bit number that was created back in 1983. There are over 4 trillion unique addresses available, but that still wasn’t enough. In the 2000s, developers started to create Internet Protocol version 6 (IPv6). This version is still in the process of replacing IPv4 and officially became an Internet Standard in 2017. With the rapid growth of the internet and its users, developers had to develop a 128-bit identifier. The problem with this is that IPv4 and IPv6 were not designed to be interoperable, so the switch has been more complicated than developers would have liked.

When it comes to routing, IPv6’s larger address space makes room for address allocation hierarchy which allows route aggregation and the expansion of routing tables. There is also device mobility and security that was considered when developing IPv6.

 

Here is a more detailed blog about why IPv6 adoption has been so slow at being implemented: 
https://www.auvik.com/franklymsp/blog/ipv6-network-design/

Also, here is a report card on the state of deployment of IPv6 and who is currently using it:
https://www.internetsociety.org/resources/2018/state-of-ipv6-deployment-2018/

Personally, I don't have any experience with IPv6 yet, but hopefully soon!

What experience have you had? What are some of the pros/cons you have heard about IPv6?

References:
https://en.wikipedia.org/wiki/IP_address
https://en.wikipedia.org/wiki/IPv6
https://www.sangoma.com/how-ip-routing-works/

Week 3 - Ethernet Standards

Ethernet Standards have been developed by non-profit organizations such as IEEE for decades. They employ the world's top experts to develop and implement the newest technology to enhance and improve our ethernet capabilities, focusing on speed and performance. Originally created by Xerox in 1973 for company use, Ethernet was then handed over to IEEE to allow them to promote a new industry standard. A working group called IEEE 802.3 was formed to focus on these standards. The 802.3 committee defines wired network standards that share the same basic frame type and network access method.

 Here are some examples of some of these standards from Mike Meyer's CompTIA Network+ Certification All-in-One Exam guide:

• 802.3i - 10 Mbps Ethernet using twisted pair cabling (1990)
• 802.3ab - Gigabit Ethernet over twisted pair (1999)
• 802.3by - 25 Gigabit Ethernet over fiber (2016)

In the beginning, the most popular Ethernet version was 10BaseT (10 Mbps using twisted pair), consisting of two or more computers connected to one central hub. In the 1990's IEEE created Gigabit Ethernet, which is the most common Ethernet used today.1000BaseT uses four pair UTP or STP to create the gigabit performance. This is also the most dominant standard of twisted pair cabling.

There are several other standard configurations that can be used, such as 1000BaseSX, which uses fiber to increase speed. In 2010, the IEEE 802.3ba committee approved 40 and 100 Gb Ethernet standards. Next up for Ethernet standards, is 800 Gb (800GBASE-R).

This article talks about the 25G Ethernet Consortium (now called the Ethernet Technology Consortium) formed by Google and Microsoft. It seems that IEEE isn't as aggressive as most people in the industry would like, so they took it upon themselves to set the future standards.

What do you think is the best Ethernet standard and why?

Do you agree with companies, aside from IEEE, forming their own committees to develop and promote the latest technology developments?

Reference:

Meyers, Mike. CompTIA Network+ Certification Exam Guide: (Exam N10-007). McGraw-Hill Education,     2018.

Week 2 - Network Topology Configurations

Simply put, a network topology is the way computers or nodes are configured on a network. There are many different types of configurations, some being replaced over the years with more secure, fail-proof methods. I will cover a few of the most common topologies and the pros/cons of using one over the other. Ultimately, it is up to you and your company to choose the most efficient configuration for your data.

One of the most common network topologies is Star, because each computer has its own connection to a central hub, making it easier to manage. If one node goes down, the others will remain connected to the network.

• Star Pros: Easy to manage network from a single location and to troubleshoot any issues, inexpensive to set up due to less cabling, ability to add or removed computers without going offline.
• Star Cons: If the central hub goes down, all connections are lost. This is a single point of failure. They are also limited in bandwidth, which makes them expensive to maintain. 

Another common topology is Bus. The bus configuration isn't used as much these days, because it is one cable connecting all of the nodes together in one direction. However, it is easy to set up and cost effective.

• Bus Pros: easy to setup, simple layout, cost effective.
• Bus Cons: vulnerable due to using only a single cable, only half-duplex data.

The Ring topology places nodes in a circle configuration, where the data can travel in one direction or both.

• Ring Pros: packet collision reduced due to one node sending data at a time, repeaters used to prevent data loss, cost-effective.
• Ring Cons: since all nodes are connected, if one goes down the whole network can go down, limited bandwidth slows down data, network must be taken offline to reconfigure or add/remove nodes.

A Mesh topology is where every single node is interconnected with each other. 

• Mesh Pros: reliable, stable, resistant to failure, eliminates single point of failure.
• Mesh Cons: time consuming and costly to set up.

Hybrid topologies are where two or more topologies are combined in a configuration. These are quite common in large companies. For example, Star Bus uses bus as a backbone of hubs for the network, with the nodes all connected to the different hubs.

• Hybrid Pros: flexibility to modify configuration.
• Hybrid Cons: costly, becomes more complex as network grows.

Ultimately, it is up to the company and network administrator to figure out the best configuration based on the needs of its users. For more information on topologies, cabling and network topology mapping, please visit https://www.dnsstuff.com/what-is-network-topology. 

What is your favorite network topology configuration and why? 

Week 1 - COVID-19 "Immunity Certificate" Technology

When I first heard about "immunity certificates," the movie Contagion came to mind. The scene where they receive their vaccines and are mandated to wear these special immunity wristbands, so everyone can tell who has the antibodies and is no longer infectious. That movie, while eerily predictable and spot on with our current real-life pandemic situation, came out in 2011. The concept of having some sort of immunity identification system is definitely not new, but the potential technology behind it is what is so intruiging to me.

As antibody testing (while still controversial in its own right) is becoming more and more available, countries worldwide will be looking to implement a tracking system for the "cured". However, paper products such as wristbands or certificates can be easily manipulated or forged. It makes sense that we would look for a more secure way to issue this sacred identifier. Currently, China has implemented a color coded system tracking everyones current health through an app on their phones. Residents are required to download this software that will tell them whether or not to quarantine and where they can and cannot go. This process is controversial because it also sends personal data to the local authorities, and is tracked not only by the government but by an outside company, so who knows how secure it really is and what data they are pulling from the users. 

Could the United States use the same type of technology in the future?

My main concern with a system like this is of course, data breach. Hackers would be all over this. Can you imagine the PII associated with this type of private health data, and how millions of people would be at risk to such an attack? Although there is such an enormous risk for something so sensitive on your smartphones, it does seem like the safest option? As opposed to losing an ID card or someone creating counterfeit wristbands to sell on the black market. We already use secure apps for banking, but even that can be vulnerable. Using technology to track the immune seems the most logical, but at what cost?

What do you suggest?