2.2 - Network Devices Flashcards
Network Interface Card (NIC)
Network Interface Card (NIC) • The fundamental network device • Every device on the network has a NIC • Computers, servers, printers, routers, switches, phones, tablets, cameras, etc. • Specific to the network type • Ethernet, WAN, wireless, etc. • Often built-in to the motherboard • Or added as an expansion card • Many options • Single port, multi-port, copper, fiber
Repeater
Receive signal, regenerate, resend • No forwarding decisions to make • Common use • Boost copper or fiber connections • Convert one network media to another • Extend wireless network reach
Hub
- “Multi-port repeater”
- Traffic going in one port is repeated to every other port
- Everything is half-duplex
- Becomes less efficient as network speeds increase
- 10 megabit / 100 megabit
- Difficult to find today
Unmanaged switches
- Very few configuration options
- Plug and play
- Fixed configuration
- No VLANs
- Very little integration with other devices
- No management protocols
- Low price point
- Simple is less expensive
Switches
- Bridging done in hardware
- Application-specific integrated circuit (ASIC)
- 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
Bridge
• Imagine a switch with two to four ports
• Makes forwarding decisions in software
• Connects different physical networks
• Can connect different topologies
• Gets around physical network size limitations /
collisions
• Distributes traffic based on MAC address
• A modern bridge is a wireless access point
• Bridges wired Ethernet to wireless
Managed switches
VLAN support • Interconnect with other switches via 802.1Q • Traffic prioritization • Voice traffic gets a higher priority • Redundancy support • Spanning Tree Protocol (STP) • External management • Simple Network Management Protocol (SNMP) • Port mirroring • Capture packets
Routers
• 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
Wireless access point (WAP)
Not a wireless router • A wireless router is a router and a WAP in a single device • WAP is a bridge • Extends the wired network onto the wireless network • Makes forwarding decisions based on MAC address
Wireless LAN controllers
• Centralized management of WAPs • A single “pane of glass” • Management functions • Deploy new access points • Performance and security monitoring • Configure and deploy changes to all sites • Report on access point use • Usually a proprietary system • The wireless controller is paired with the access points • Can also be cloud-based • Manage the console from anywhere
Firewalls
Filters traffic by port number
• OSI layer 4 (TCP/UDP)
• Some firewalls can filter through OSI layer 7
• 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
Ethernet over Power (EOP)
• Also called Power-line communication (PLC)
• IEEE standard 1901
• 500 megabits per second
• Standard includes links to the premise, intra-building
networking, vehicles, smart energy devices, and more
PoE switch
Power over Ethernet
• Commonly marked on the switch or interfaces
Power over Ethernet
- Power provided on an Ethernet cable
- One wire for both network and electricity
- Phones, cameras, wireless access points
- Useful in difficult-to-power areas
- Power provided at the switch
- Built-in power - Endspans
- In-line power injector - Midspans
Patch panels
- Combination 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
- No special tools
- Use existing cables
