Advanced Networking Devices Flashcards
VPN
Virtual Private Network
- encrypted tunnel between a computer or a remote network and a private network through the internet
Tunnel Endpoints
the ends of a tunnel where the data is encrypted and decrypted
VPN Tunnel
VPN creates virtual NIC on client (endpoint 1), creates a virtual cable (vpn tunnel) to the server (endpoint 2)
PPTP VPN
Point-to-Point Tunneling Protocol
- advanced version of PPP
- server endpoint is a program on Windows server called RRAS (Routing and Remote Access Service)
- every OS comes with some built in client that supports PPTP
- commonly called “Host-to-Site Connection”
L2TP VPN
Layer 2 Tunneling Protocol
- VPN Concentrator (can run on almost any connection)
- no auth or encryption (uses IPSec)
- supported by every OS VPN client
host-to-site or client-to-site connection
Single connection between user and network
site-to-site connection
Using two VPN concentrators to connect two networks
- slow but inexpensive
SSL VPN
- do not require any special software
- connects using web browser
- secured using TSL
DTLS VPN
Datagram TLS
- uses UDP instead of TCP
DMVPN
Dynamic Multipoint VPN
- enables direct VPN connection between multiple locations directly
- uses IPSec
default gateway on a switch
ip address of the router
in-band and out-of-band management
in-band - can access switch over network
out-of-band - only a port can be used to access switch
console router
a router with out-of-band management capabilities
VLAN
Virtual LAN
- can take a single broadcast domain and chop it up into multiple broadcast domains
- done by assigning each port a specific VLAN
Trunking
process of transferring traffic between one or more switches
trunk port
a switch port configured to carry all traffic, regardless of VLAN, between all switches on a LAN
native VLAN
the VLAN designation for a trunk port
standard that enables you to connect switches from different manufacturers?
IEEE 802.1Q
VLAN Assignment
the process of assigning ports to VLANs
static vs dynamic VLANs
static - based on port
dynamic - based on MAC address
access ports
opposite of trunk ports… connect workstations
Why would you want to change a native VLAN
to mitigate against double-tagging attacks
VTP
VLAN Trunking Protocol
- automates updating of multiple VLAN switches
- put switch in one of three states: server, client or tranparent
VTP Pruning
miniminzing broadcast traffic
useful for larger-scale networks
VTP state transparent
tells the switch not to update, but to hold its manual settings
interVLAN Routing
process of making a router work between two VLANs
Relay Agent
- also called DHCP relay
- router will pass DHCP messages across the router interfaces
- single DHCP server to server addresses to multiple networks or subnetworks
troubleshooting VLANs
all about assingment
- if you give an incorrect VLAN assignement to a device, you wont be able to see it or the device won’t access resources
- fix: change VLAN assignemnt
Difference between layer 2 and 3 switches
2 - forwards traffic based on MAC addresses
3 - forwards traffic based on IP addresses
load balancing
making a bunch of servers look like a single server, creating a server cluster
DNS Load Balancing
DNS server for domain has multiple “A” records for the same FQDN
- DNS server cycles around records
content switch
works at layer 7
- designed to work with web servers
- can read incoming http and https requests
- also called content filter
QoS
Quality of Service
- prioritize traffic based on certain rules
traffic shaping
control the flow of packets into or out of the network based on type of packet or other rules
shapers
routers and switches that can impletment traffic shaping
IDS
Intrusion detection system
- inspects packets looking for intrusions
- cant stop attack, but can request assistance from other devices, like a firewall
IPS
Intrustion prevention system
- sits directly in the flow of network traffic
- can stop an attack
- creates latency
- if IPS goes down, link can go down
- can block packets based on IP address, port number or application type
- might even fix packets on-the-fly
signatures
detectable patterns
definition files
collection of signatures for known malware
HIDS
Host-based IDS
- runs on individual systems
- monitors for events like system file modification or registry changes
NIDS
Network-based IDS
HIPS
Host-based IPS
NIPS
Network-based IPS
port mirroring
copy data from any or all physical ports on a switch to a single physical port
local - ports on same switch
remote - send data anywhere
proxy server
sits in between clients and external servers
- handles all requests for client
- keeps server from knowing where client is
- using caching for resources to speed up later requests
forward proxy server
a proxy server working for clients
reverse proxy server
a proxy server working for hosts
