CCNA-Notes/02. Interfaces and Cables - CCNA.md

id, aliases, tags

id	aliases	tags
1771825730-VZFA	02. Interfaces and Cables - CCNA	CCNA

Interfaces and Cables

Front of a switch example phrase above the interfaces 10/100/1000 Base-T Ports ( 1 -24) - Ports are Auto MDIX

RJ-45

Registerred Jack

Etrhernet

Etrhernet is a collection of network protocols/standards.

Network Protocols

Why do we need network protocols For Industry standard that everybody follows

Bits and Bytes

it a value represented by 0 and 1 a bytes is a series of 8 bits

Speed is measured in bits per second (kbps, Mbps, Gbps, etc) not bytes per seconds.

However for Hard drives we count the bytes

1 kilobit (kb) - 1,000 bits 1 megabit (Mb) - 1,000,000 bits 1 gigabit (Gb) - 1,000,000,000 bits 1 terabit (Tb) - 1,000,000 bits

Etrhernet standards

• Defined in the IEEE 802.3 standard in 1983
• IEEE = Institute of Electrical and Electronics Engineers

Copper Ethernet standard

Speed	Common name	IEEE	Informal Name	Maximum Length
10 Mbps	Ethernet	802.3i	10BASE-T	100m
100 Mbps	Fast Ethernet	802.3u	100BASE-T	100m
1 Gbps	Gigabit Ethernet	802.3ab	1000BASE-T	100m
10 Gbps	10 Gig Ethernet	802.3an	10GBASE-T	100m

BASE T

Base = refers to baseband signaling T = twitsted pair

UTP Cables

Unshielded Twisted Pair Twisted mean that there sensitive against EMI Electronic Magnetic Interference they got 8 pins

10Base-T and 100Base-T = 2 pairs (4 wires)

1000Base-T and 10GBase-T = 4pairs (8 wires)

UTP Cables (10Base-T, 100 Base-T)

Full-Duplex transmission Both devices can send and received data at the same. no colission while occur

Straight-through cable

Transmit 1 - 1 Receive (TX) 2 - 2 (RX) Recieve 3 - 3 Transmit 4 4 5 5 (RX) 6 - 6 (TX) 7 7 8 8

Crossover cable

Transmit 1 - 3 Transmit (TX) 2 - 6 (TX) Recieve 3 - 1 Receive 4 4 5 5 (RX) 6 - 2 (RX) 7 7 8 8

Chart

Device Type	Transmit (TX) Pins	Recieve (RX) Pins
Router	1 and 2	3 and 6
Firewall	1 and 2	3 and 6
PC	1 and 2	3 and 6
Switch	3 and 6	1 and 2

Auto MDI-X

allows devices to automatically detect and adjust the the pins for transmiting data prevent colissions

UTP Cables (10Base-T, 100 Base-T)

Straight-through cable

Each pair is bidirectional

the pair are

1 and 2 3 and 6 4 and 5 7 and 8

Fiber-Optic Connection

SFP Transceiver Small-Factor Pluggable for Fiber Optics cable

Send light over glass fiber

TX - RX RX - TX

there are 4 layers for this cable

1 : the fiberglass core itself 2 : cladding that reflects light 3 : a protective buffer 4 : the outer jacket of the cable

single-mode and multimode fiber

Multimode fiber

• Core diameter is wider than single mode fiber.
• Allow mutiple angles (modes) of light waves to enter the fiberglass core
• Allows longer cables tha UTP but shorter cables than single-mode fiber.
• cheaper than single-mode fiber (due to cheaper LED-based SFP transmitters)

Single-Mode Fiber

• Core diameter is narrower than multimode fiber
• Light enters at a single angle (mode) from alaser-based transmitter
• Allows longer cables than both UTP and multimode fiber
• More expensive than multimode fiber (due to more expnesive laser based transmitters)

Fiber-Optic cables standards

Speed	Cable Type	IEEE	Informal Name	Maximum Length
1 Gbps	multi or single-mode	802.3z	1000BASE-LX	550m(MM) 5km (SM)
10 Gbps	Multi-mode	802.3ae	10GBASE-SR	400m
10 Gbps	Single-Mode	802.3ae	10GBASE-LR	10km
10 Gbps	Single-Mode	802.3ae	10GBASE-ER	30km

UTP vs Fiber-Optic Cabling

• UTP

  • Lower cost than fiber optic.
  • Shorter Maximum distance than fiber0-optic (100m).
  • Can be vulnerable to EMI
  • RJ45 ports used with UTP are cheaper than SFP ports.
  • Emit (leak) a faint signal outside of the cable, which can be copied (= security risk)

• Fiber-Optic

  • Higher cost than UTP.
  • Longer maximum distance than UTP.
  • No vulnerability to EMI.
  • SFP ports are more expnsive than RJ45 ports (singl-mode is more expensive than multimode).
  • Does not emit any signal outside of the cable (=no security risk)