Chapter 12: Advanced Networking Devices

Question 1

What is a virtual private network?

Answer 1

-all computers should be on the same network. have the same network id.

Question 2

What is PPTP?

Answer 2

Point-to-Point tunneling protocol.

• places end points on the client and the server.
• server endpoint: routing and remote access server.
• only available on a windows server.

Question 3

What is L2TP?

Answer 3

Layer 2 Tunneling Protocol

• moved endpoint on local LAN from server program to a VPN-capable router. “VPN concentrator”
• no authentication or encryption.
• uses IPsec for security needs.

Question 4

What is SSLVPN

Answer 4

• works at application layer
• don’t need special client software
• connect to VPN server with web browser.
• SSL portal: secure webpage
• tunnel VPNs: web browser runs java or flash

Question 5

What is a VLAN?

Answer 5

• segments networks using switches

- takes a single broadcast domain and chop it up into multiple broadcast domains.

Question 6

What is trunking?

Answer 6

transferring VLAN traffic between two or more switches.

• Interlink switch(ISL): cisco version
• IEEE 802.1Q trunk standard

Question 7

what is VTP?

Answer 7

Virtual trunk protocol

• automate the updating of multiple VLAN switches.
• put switch into state of server, client or transparetn
• changes to VLAN of server switch propagate to clients
• transparent mode: does not update settings.

Question 8

Describe intervlan routing.

Answer 8

• each vlan is a separate broadcast domain
• to get data from one VLAN to another need to use a router.
• need a switch that can create virtual routers to interconnect VLANs.
• multilayerswitch: operates at layer 2 and 3 and is very useful in load balancing, QoS, network protection.

Question 9

What is load balancing?

Answer 9

-a bunch of servers look like a single server through a server cluster.

Question 10

What is DNS load balancing?

Answer 10

• browser caching reduces effectiveness.
• each web server gets its own public ip address.
• each DNS server for the domain has multiple “A” DNS records that each has the same FQDN.
• DNS server cycles around the records “Round robin”
• BIND DNS: similar to round robin; can add weighting.

Question 11

What is a multilayer or content switch

Answer 11

• web servers behing single IP
• multilayer switch(layer 3 and 4): router performs NAT and port forwarding and can query hidden web servers and send HTTP request to servers with less load.
• content switch: Layer 7 (content filter network appliance): can read incoming HTTP(S) requests, can handle SSL certs and cookies, pass cookie to HTTP requesters(web browsers).

Question 12

Describe IDS.

Answer 12

Intrusion Detection System

• runs on dedicated IDS box
• inspects incoming packets looking for intrustions such as virus, illegal login attempts

Question 13

Describe an intrusion prevention system.

Answer 13

-react to an attack.