Ethernet Fundamentals Flashcards
10BASE-T
Cat3; 10 mbps 100 meters
Carrier Sense Multiple Access with Collision Detection (CSMA/CD)
Prevents collisions by using carrier-sensing to defer transmissions until no other stations are transmitting; waiting for the gap in the convo to speak; if you speak when another person speaks, you wait and try again later
Collision Domain
each area of the network that shares a single segment; any time you have devices on the same hub, you are sharing the same collision domain; devices operate in half duplex when connected to a hub
Ethernet switch
increases scalability of a network by creating multiple collision domains; every switch port is its own collision domain; full duplex
bandwidth
measures how many bits the network can transmit per second
100BASE-FX
MMF
100 Mbps
2 Kilometers
100BASE-SX
MMF
100 Mbps
300 Meters
1000BASE-SX
MMF
1000 Mbps
220-500 Meters
1000BASE-LX
SMF/MMF
1000 Mbps
5 Kilometers/550 meters
10GBASE-SR
MMF
10 Gbps
400 Meters
10GBASE-LR
SMF
10 Gbps
10 Kilometers
If you see S in the name for Fiber, it must be MMF
Don’t forget that!
Hub
Also known as a multiport repeater. It is a layer 1 devices that connects multiple network devices and workstations
Smart Hub
Active hub with enhanced features like SNMP
Bridge
Analyzes source MAC addresses and makes intelligent forwarding decisions based on the destination MAC in the frames
Switch
Also known as a multiport bridge, it is a layer 2 device
Router
Layer 3 Device that connect muliple networks and makes forwarding decisions based on logical network infomation
Layer 3 Switch
Makes Layer 3 routing decisions and then interconnects entire networks, not just network segments; just combines a switch and a router
Link Aggregation (IEEE 802.3ad)
combines multiple physical connections into a single logical connection to minimize or prevent congestion
Power Over Ethernet (PoE 802.3af - 15.4 watts, PoE+ 802.3at - 25.5 watts)
Supplies electrical power over ethernet and requires Cat 5 or higher copper cable
Port Monitoring or Mirroring
Makes a copy of all traffic destined for a port and sends it to another port
User Authentication (802.1x)
Requires users to authenticate themselves before gaining access to the network
Management Access and Authentication
SSH - Remote Admin program that allows connection to the switch over the network
or a Console Port - allows for local admin of the switch using a separate laptop and a rollover cable (DB9 to RJ45)
OOB (out of band) management
keeps all network configuration devices on a separate network
First Hop Redundancy
Uses Hot Standby Router Protocol (HRSP) to create virtual IP and MAC addresses to provide active and standby routers
MAC Filtering
permits or denies traffic based on device’s MAC address
Traffic Filtering
Permits or denies traffic based on IP addresses or application ports
Quality of Service (QoS)
Forwards traffic based on priority markers
Spanning Tree Protocol (802.1d)
Permits redundant links between switches and prevents looping of network traffic
Broadcast Storm
Multiple copies of frames being forwarded back and forth which then consumes the network
Link Cost
Faster cables have lower cost, while slower cables have higher cost
VLAN
Allows different logical networks to share the same physical hardware and provides added security and efficiency
VLAN Trunking (802.1q)
Multiple VLANs transmitted over the same physical cable
VPN
creates a secure VPN tunnel over a public network
VPN concentrator
Terminates VPN tunnels and allows for multiple VPN connections in one location
VPN Headend
a specific type of VPN concentrator
Firewall
placed at the boundary of your network; inside to outside or outside to inside
Next Gen Firewall (NXGF)
works at layer 7; detects and prevents attacks
Proxy Server
A specialized device that makes requests to an external network on behalf of a client
Load Balancer
Distributes incoming requests across various servers in a server farm
Content Engine/Caching Engine
Dedicated appliance that performs the caching functions of a proxy server
ICS
Industrial Control System - Describes the different types of control systems and associated instrumentation
SCADA
Supervisory Control and Data Acquisition - Acquires and transmits data from different systems to a central panel for monitoring and control
