Assignment
Date: 9/8/2004
Due Day:
9/15/2004
Related Material: http://cs.uccs.edu/~cs522/intro/pcnetsetup/pcnetsetup.htm;
chapter 5.6.
Description:
Exercise 1. Classless Address Notation
Problem 1. A router has the following
(CIDR) entries in its routing table:
Address/mask Next hop
135.46.56.0/22 Interface 0
135.46.60.0/22 Interface 1
192.53.40.0/23 Router 1
default Router
2
For each of the following IP addresses, what does the router do if a packet
with that address arrives?
(a) 135.46.63.10 (b) 135.46.57.14 (c) 135.46.52.2 (d) 192.53.40.7 (e)
192.53.56
From the first entry of the routing table, it indicates arbor located in a wired Ethernet subnet with IP address 128.198.160.0 and genmask (or called netmask) 255.255.224.0. The second entry indicates arbor also has wireless LAN card on a subnet identified with 128.198.80.0 and genmask 255.255.255.0.
---
128.198.1.250 ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 2997ms
rtt min/avg/max/mdev = 0.144/0.300/0.764/0.268 ms
sanluis.uccs.edu>
/sbin/arp -a
math.uccs.edu (128.198.168.202) at 00:06:5B:F6:E4:CC [ether] on eth0
lincoln.eas.uccs.edu (128.198.160.64) at 00:06:5B:0F:1A:19 [ether] on
eth0
evans.eas.uccs.edu (128.198.160.66) at 00:06:5B:0F:17:10 [ether] on eth0
sunshine.uccs.edu (128.198.162.68) at 00:06:5B:F6:E4:CC [ether] on eth0
? (128.198.160.1) at 00:00:0C:07:AC:01 [ether] on
eth0
chow.uccs.edu (128.198.161.110) at 00:00:39:B4:86:E0 [ether] on eth0
Non-authoritative
answer:
Name: blanca.uccs.edu
Address: 128.198.162.60
Therefore the source IP address is 128.198.162.60.
The destination IP address is 128.198.160.64.
The source mac address can be found using /sbin/ifconfig
blanca.uccs.edu> /sbin/ifconfig
eth0 Link encap:Ethernet HWaddr 00:B0:D0:D1:13:5C
inet addr:128.198.162.60 Bcast:128.198.191.255 Mask:255.255.224.0
Therefore the source MAC address is 00:B0:D0:D1:13:5C
The destination MAC address can be found with /sbin/arp -a command:
blanca.uccs.edu> /sbin/arp -a 128.198.160.64
lincoln.eas.uccs.edu (128.198.160.64) at 00:06:5B:0F:1A:18 [ether] on
eth0
Therefore the destination MAC address is 00:06:5B:0F:1A:18.