Network

Question 1

Router

Answer 1

Routes traffic between IP subnets
- Makes forwarding decisions based on IP address
- Routers inside of switches sometimes called “Layer 3 switches”
Often connects diverse network types
- LAN, WAN, copper, fiber

Question 2

Switch

Answer 2

Bridging done in hardware
- ASIC (Application-Specific Integrated Circuit) very fast throughput
- Forwards traffic based on data link address
Many ports and features
- The core of an enterprise network
- May provide Power over Ethernet (PoE)
Multilayer switch
- Includes routing functionality

Question 3

Unmanaged switches

Answer 3

Very few configuration options
- Plug and play
Fixed configuration
- No VLANs
Very little integration w/ other devices
- No management protocols
Low price point
- Simple is less expensive

Question 4

Managed switches

Answer 4

VLAN support
- Interconnect w/ other switches via 802.1Q
Traffic prioritization
- Voice traffic gets a higher priority
Redundancy support
- STP (Support Tree Protocol) prevents looping
Port mirroring
- Capture packets
External management
SNMP

Question 5

Access point

Answer 5

Not a wireless router
- A wireless router is a router and an access point in a single device
An access point is a bridge
- Extends the wired network into the wireless network
- Makes forwarding decisions based on MAC address

Question 6

Patch Panel

Answer 6

Combo of punch-down blocks and RJ-45 connectors
Runs from desks are made once
- Permanently punched down to patch panel
Patch Panel to switch can be easily changed
- unplug ethernet from current space and plug into new space

Question 7

Firewall

Answer 7

Filters traffic by port number
- OSI layer 4 (TCP/UDP)
- Some firewalls can filter based in the application (Layer 7 device)
Can encrypt traffic into/out of the network
- Protect your traffic between sites
Can proxy traffic
- A common security technique
Most firewalls can be layer 3 devices (routers)
- Usually sits on the ingress/egress of the network

Question 8

PoE

Answer 8

Power provided on an Ethernet cable
- 1 wire for network and electricity
- Phones, cameras, wireless access points
- Useful in difficult-to-power areas
- Commonly marked on the switch or interfaces

Question 9

PoE, PoE+, PoE++

Answer 9

PoE: IEEE 802.3af-2003
- Original PoE spec
- Now part of 802.3 standard
- 15.4 watts DC power, 350 mA max current
PoE+: IEEE 802.3at-2009
- Also now part of 802.3 standard
-25.5 watts DC power, 600 mA max current
PoE++: IEEE 802.3bt-2018
- 51 watts (Type 3), 600 mA max current
- 71.3 watts(Type 4), 960 mA max current
- PoE with 10GBASE-T

Question 10

Hub

Answer 10

AKA “Multi-port repeater”
- Traffic going in 1 port is repeated to every other port
Everything is half-duplex
Becomes less efficient as traffic increases
10 megabit/100 megabit
Difficult to find today (outdated)

Question 11

Cable modem

Answer 11

Broadband
- Transmission across multiple frequencies
- Different traffic types
Data on the “cable” network
- DOCSIS (Data Over Cable Service Interface Specification)
High-speed networking
- Speeds up to 1 Gigabit/s are available
Multiple services
- Data, voice, video

Question 12

DSL modem

Answer 12

ADSL (Asymmetric Digital Subscriber Line)
- Uses telephone lines
Download speed is faster that uploading speed (asymmetric)
- ~10,000 foot limitation from the central office (CO)
- 52 Mbit/s downstream / 16 Mbit/s upstream are common
- Faster speeds may be possible if closer to the CO

Question 13

ONT

Answer 13

Optical network terminal
- Fiber to the premisis
Connect the ISP fiber network to the copper network
- Demarcation point (demark) in the data center
- Terminal box on the side of the building
Line of responsibility
- One side of the box is the ISP
- Other side of the box is your network