Course 3: Routers
Explain why a customer's network must be using a different IP address space than the network you are on in order to connect to the customer's network using VPN
if the addresses are the same, your computer will think its the local network and never contact the VPN router
Demilitarized Zone (DMZ)
if you can't bridge mode, allows all network traffic to be forwarded to the ISP address of your choosing, but keeps routing in place. Allows use of DDNS or CPN. Also does not disable NAT.
Compare and contrast InterVLAN Routing and "multicast routing"
interVLAN is for unicast while m-routing (mDNS) is for multicast
Explain how unicast and multicast traffic is routed between VLANs
interVLAN routing is enabled
Which layer routers function on in the OSI model
layer 3: network
Virtual Private Network (VPN)
makes a private network securely assessable form across the internet
Port Forwarding
open 1 or more ports on the router's WAN side. When the router sees these, it forwards it to tan internal host
Explain why some routers have more than one WAN port
reliability: maintain connection if one goes down
Compare and contrast static, dynamic, and reserved IP addresses
static IP: assign manually, predictable, time consuming, human error dynamic IP: router assigns automatically reserved IP: keep range free for specific hosts (MAC)
Explain how the router "declares" the network
the router is both the default gateway and DHCP server
Explain the impact routing hops have on a network's performance
they create more latency hops then switching hops
Use the command traceroute to show routing hops
tracert google.com
Network Address Translation (NAT)
translates public IP addresses to private IP addresses and vice versa
Compare and contrast trunk ports and access ports
trunk port: passes all traffic Access: passes only specific tagged traffic
Bridge Mode
turns off router functionality turning LAN signal into WAN signal
Explain the few cases that you may want to use port forwarding on a customer's network
using a phone app to view camera footage, remotely stream from plex server, essentially legacy apps not on the cloud yet
Explain when a PPPoE connection may be the required WAN connection
when the customer has a DSL phone line provider
4 steps of the "Plan the LAN" workflow
1. size the network 2. select the networks address 3. assign addresses for the hosts 4. implement the network
Explain how to diagnose if there is an extra, unnecessary routing hop on a network
After using tracert, if the second IP is 10., 172.16, or 192.168
Explain how DHCP leases work
devices request an IP for x amount of time (x determined by network administrator)
Explain how to manage a "combo unit" from an ISP
disable wireless, connect only the router, put it into bridge mode
Compare and contrast a router's WAN configuration with its LAN configuration
WAN: ISP provides IP and subnet LAN: private IP range, you can modify DHCP range, private subnet mask
Trunking
a port that passes both tagged and untagged traffic
Demonstrate how to plan a network IP addressing strategy
add up hosts, plan subnet mask around # of hosts, create static/reserved/DHCP ranges
Explain how the subnet mask determines the number of IP addresses available for hosts on a network
add up in binary how many hosts from the host #s (256 on last octet)
Dynamic DNS (DDNS)
allows access to a private router with a fixed host name (www.host.com/person) incase the ISP changes the IP address
VLAN
another LAN logically separated on its own subnet or broadcast domain
VLAN tagging
data from a VLAN gets a VID tagged to its frame
