Understanding Ethernet and Fiber Op

#network #ethernet #security #beginners

Greetings all,

Back at it and not wasting time at all. I mean eh, it is 2024 right?! Goals were drafted and now the skill must be crafted. In the prior post, I spoke a bit about the world of networking and the basics. Things such as switches and routers were discussed as well as type of networks. Now I go a bit more into the interfaces and cable side of things. Yes, many would say to skip this part, but in my case I want to be a master of the field cybersecurity. I also have a background in electronics so a bit of this is a review well needed. Well, let's not wait and get into more of the notes surrounding networking. Specifically Ethernet and Fiber-optic cable will be reviewed with much in addition. Ok... I'll hush. LOL.

What are bits and bytes?

Bit:

A value represented by 0 and 1. When communicating over copper cable, the data is sent is interpreted by the receive device using 0 or 1.

Byte:

A series of 8 bits. 8 bits = 1 Byte.

Remember, speed is measured by bits per second. Kbps, Mbps, Gbps, etc. Never bytes per second.

1 Kb = 1,000 bits
1 Mb = 1,000,000 bits
1 Gb = 1,000,000,000 bits
1 Tb = 1,000,000,000,000 bits

What is Ethernet?

A collection of network protocols and standards.

What is RJ-45?

RJ-45:( Registered Jack- 45 )ie: Ethernet Connection

What are Ethernet Standards?

IEEE 802.3 standard in 1983. (Institute of Electrical and Electronics Engineers)
ie: 10-BASE-T, 100BASE-T, 1000BASE-T, 10GBASE-T)
Be sure to look up the standards listed above.

Listed in the standards are the following:

Speed
Common Name
IEEE Standard
Informal Name
Max Length

What are UTP Cables?
(ie: Cat 6 cable )

UnShielded Twisted Pair (No metallic shield which it vulnerable to electrical interference)
The Twist protects against EMI (Electromagnetic Interference)
Lower cost than fiber-optic
Shorter max than fiber-optic (up to 100 meters)
RJ45 ports usd with UTP are cheaper than SFP ports.
Emit (leak) a faint signal outside of the cable which can give security risks.

What are Fiber Optic Cable?

Sends light over glass fibers having one connection to send and one connection to receive.

Two Types of Fiber-Optic Cable are below:

Single-mode Fiber Optic Cables:

core diameter is narrower
light enters at a single angle mode from a laser based transmitter.
allows longer cables than both UTP and multimode fiber.
more expensive than multimode fiber (due to more expensive laser-based SFP transmitters)
They use separate cable to send and receive connections
1. fiberglass core
2. cladding that reflects light
3. a protective buffer
4. the outer jacket of the cable.