• Internet - WAN of LANs
• ISPs - The old days
• ISPs - Today -LAB
• ISP architectures- LAB
• Internet statistics
• Internet bottlenecks and how they impact you- LAB
• Internet technologies for tomorrow
  TCP/IP architectures
• Host vs. networks
• Routing
• Subnets - VLSM vs. CIDR

Domain Name Server (DNS)

• Old days
• Today
• DNS architecture -LAB
• Delegating name space -LAB
• Delegating authority
• Reverse lookups and how to debug -LAB

SMTP

• The protocol
• Attachments - MIME vs. UUENCODE
• Gateway integration techniques
• DNS integration - LAB

World Wide Web (WWW)

• Basic browsing
• Transparent proxies
• Caching proxies

Firewalls

• Firewall basics
• The old days
• Today's firewalls
• Application vs. stateful vs. router
• Strong vs. weak firewalls
• Best configurations
• Smart vs. dumb proxies

Break and Fix

• Debug broken DNS - LAB
• Debug broken Email - LAB

Upon completion of this course, you will be able to answer the following questions:

1. Detail the operations of the protocol used to correlate IP addresses to MAC addresses.
2. True or False: When a router receives a packet, it changes the destination IP address and forwards the packet to the next  hop.
3. What is the "natural mask" for a Class B network?
4. If a network is "subnetted", what does this infer?
5. At what layer of the TCP/IP stack are TCP and UDP? How are they alike and how do they differ?
6. ½ of a class "C" is:

7. 1. 255.255.255.192
   2. 255.255.255.128
   3. 255.255.128.0
   4. 255.255.255.240

8. What is 0.0.0.0?
9. What is a NAP and how do you use traceroute as a tool to indicate if it is causing problems for your Internet connection?
10. What is CIDR?
11. What does the InterNIC do, what is the new relationship to ICANN and why does this negatively impact your organization when you try to register domain names?
12. What is RIP? How does it differ from static routing? What would you use on the firewall and why?
13. Why would you use address translation if your internal network address is 10.0.0.0?
14. What service is used to resolve names to IP addresses?
15. What is the optimal architecture for an external DNS server in a firewalled environment and why?
16. Why do you want your ISP to handle secondary DNS services with your site as the primary?
17. What command-line tools are available to determine if zone-transfers are occurring and what are the commands?
18. What field and value should you set your DNS SOA to if you are about to update the record for your WWW site?
19. How does DNS handle MX records with the same priority and why would you setup your site to do this?
20. How can you use Telnet to determine if your SMTP service is working properly?
21. What do the following servers listen on?

22. 1. ftp
    2. telnet
    3. smtp
    4. http

23. If you are tracerouting from inside your network to an address out on the internet and the traceroute stops at your main internal router, what does that tell you?