Networking Homework - Integrated Concepts
Networking homework - Integrated Concepts
Name: ____________________________
1. Packet Flow
In this configuration, R1 is a router implementing NAT.
Each switch has many hosts, but only one is shown for simplicity.
Only the last two bytes of each MAC is shown. eth0 and eth2 are the ports on
the router that connect to the switches. MAC addresses are shown as 16, not
48 bit, addresses to save writing.
<![CDATA[
Note: The netmask of the internal "10" network is 255.255.255.0
Router at ISP
75.4.1.4 MAC FF:FE
|
| eth0: 10.100.100.1 MAC 67:46
----atm1--R1-eth0-----(switch link 22)---SwitchA-(switch link 33)
75.4.1.5 | |-10.100.100.200 MAC 56:BE
MAC 91:22 |eth2: 10.100.99.1 MAC 9A:2F
|
|
| |--(switch link 10)---10.100.99.10 MAC 11:11
|-(switch link 4)-SwitchB
|
switch link 6|
SwitchC
|
+---(switch link 9)- 10.100.99.100 MAC 42:AA
]]>
In this network, host 10.100.99.100 sends a frame to a web server at
9.4.2.1 port 80. Various addresses will change as the frame travels along
the path.
The links traversed are:
- Switch link 9 from host to Switch C
- Switch link 6 from SwitchC to Switch B
- Switch link 4 from SwitchB to router port eth2
- Router port atm1 to ISP router.
Complete the addresses in the table below. Hint: you do NOT have to
make up any numbers. Given the values filled in, all other
boxes have only one possible answer.
<![CDATA[
+------------------------------------------------------------------------------+
| src MAC | dest MAC | src IP | dest IP | src port |dest port| LINK |
+------------------------------------------------------------------------------+
| | 9A:2F |10.100.99.100| 9.4.2.1 | 55555 | | 1 |
| | | | | | | |
+------------------------------------------------------------------------------+
| 42:AA | |10.100.99.100| | | | 2 |
| | | | | | | |
+------------------------------------------------------------------------------+
| | | | 9.4.2.1 | | 80 | 3 |
| | | | | | | |
+------------------------------------------------------------------------------+
| | FF:FE | | | 34567 | | 4 |
| | | | | | | |
+------------------------------------------------------------------------------+
]]>
In the above network,
for a datagram between these sets of IP addresses, mark which ones
will go through R1 (rather than just through a switch).
- 10.100.99.10 <--> 10.100.100.200
- 10.100.99.100 <--> 10.100.99.10
- 10.100.99.10 <--> 9.9.1.5
- 10.100.100.200 <--> 192.42.153.153
Using Tools
While away from campus over Thanksgiving, find your IP address, name,
and whois information for you Internet connection.
First find your LOCAL IP address with ipconfig: __________________________
Now find your default router on the local subnet using netstat -nr:
__________________________________
https://www.whatismyip.com - shows my EXTERNAL IP as: __________________________
nslookup my-external-ip-address shows name: ________________________________
Use https://whois.icann.org/en and put in the DNS name of your connection.
Who does it say it is:
__________________________________________________
_________________________________________________
_________________________________________________